/* ==========================================
   1. CSS VARIABLES (DESIGN SYSTEM)
   ========================================== */
:root {
    --bg-primary: #F8FAFC;
    --bg-secondary: #FFFFFF;
    --bg-tertiary: #EEF2F6;
    --text-primary: #0F172A;
    --text-secondary: #475569;
    --text-tertiary: #64748B;
    --color-primary: #2563EB; /* Medical Blue */
    --color-primary-hover: #1D4ED8;
    --color-primary-light: rgba(37, 99, 235, 0.1);
    --color-secondary: #10B981; /* Health Green */
    --color-secondary-hover: #059669;
    --color-secondary-light: rgba(16, 185, 129, 0.1);
    --color-accent: #F59E0B; /* Orange Warning */
    --color-danger: #EF4444; /* Blood sugar spike */
    --glass-bg: rgba(255, 255, 255, 0.75);
    --glass-border: rgba(255, 255, 255, 0.5);
    --card-shadow: 0 10px 30px -10px rgba(15, 23, 42, 0.08), 0 1px 3px rgba(15, 23, 42, 0.03);
    --glow-primary: rgba(37, 99, 235, 0.15);
    --glow-secondary: rgba(16, 185, 129, 0.15);
    --border-radius: 16px;
    --border-color: #E2E8F0;
    --transition-speed: 0.3s;
}

[data-theme="dark"] {
    --bg-primary: #0F172A; /* Deep Navy */
    --bg-secondary: #1E293B; /* Slate Blue */
    --bg-tertiary: #0F172A;
    --text-primary: #F8FAFC;
    --text-secondary: #94A3B8;
    --text-tertiary: #64748B;
    --color-primary: #3B82F6;
    --color-primary-hover: #60A5FA;
    --color-primary-light: rgba(59, 130, 246, 0.15);
    --color-secondary: #34D399;
    --color-secondary-hover: #6EE7B7;
    --color-secondary-light: rgba(52, 211, 153, 0.15);
    --glass-bg: rgba(30, 41, 59, 0.7);
    --glass-border: rgba(255, 255, 255, 0.05);
    --card-shadow: 0 15px 35px -10px rgba(0, 0, 0, 0.3), 0 5px 15px -5px rgba(0, 0, 0, 0.2);
    --glow-primary: rgba(59, 130, 246, 0.25);
    --glow-secondary: rgba(52, 211, 153, 0.25);
    --border-color: #334155;
}

/* ==========================================
   2. GENERAL RESETS & LAYOUT
   ========================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', sans-serif;
    scroll-behavior: smooth;
}

body {
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: background-color var(--transition-speed), color var(--transition-speed);
    overflow-x: hidden;
    line-height: 1.6;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Outfit', sans-serif;
    font-weight: 700;
    letter-spacing: -0.02em;
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

button, .btn {
    cursor: pointer;
    border: none;
    outline: none;
    font-family: 'Inter', sans-serif;
    transition: all var(--transition-speed) cubic-bezier(0.4, 0, 0.2, 1);
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

section {
    padding: 100px 0;
    position: relative;
}

/* Gradients */
.gradient-text-blue {
    background: linear-gradient(135deg, var(--color-primary), #38BDF8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.gradient-text-green {
    background: linear-gradient(135deg, var(--color-secondary), #34D399);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.gradient-text-mixed {
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* ==========================================
   3. LOADER
   ========================================== */
.loader-wrapper {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: var(--bg-primary);
    z-index: 9999;
    display: flex;
    justify-content: center;
    align-items: center;
    transition: opacity 0.5s ease, visibility 0.5s ease;
}

.loader-wrapper.fade-out {
    opacity: 0;
    visibility: hidden;
}

.loader {
    position: relative;
    width: 80px;
    height: 80px;
}

.loader svg {
    width: 100%;
    height: 100%;
    stroke: var(--color-primary);
    stroke-width: 4;
    stroke-linecap: round;
    fill: none;
    animation: pulse-loader 1.5s ease-in-out infinite;
}

@keyframes pulse-loader {
    0% {
        stroke-dasharray: 1, 150;
        stroke-dashoffset: 0;
        stroke: var(--color-primary);
    }
    50% {
        stroke-dasharray: 90, 150;
        stroke-dashoffset: -35;
        stroke: var(--color-secondary);
    }
    100% {
        stroke-dasharray: 90, 150;
        stroke-dashoffset: -124;
        stroke: var(--color-primary);
    }
}

/* ==========================================
   4. NAVIGATION BAR (HEADER)
   ========================================== */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background-color: transparent;
    border-bottom: 1px solid transparent;
    transition: all 0.4s ease;
}

header.scrolled {
    background-color: var(--glass-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--glass-border);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.03);
    padding: 12px 0;
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 20px;
    padding-bottom: 20px;
    transition: all 0.4s ease;
}

header.scrolled .container {
    padding-top: 0;
    padding-bottom: 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-family: 'Outfit', sans-serif;
    font-size: 24px;
    font-weight: 800;
    letter-spacing: -0.03em;
    color: var(--text-primary);
}

.logo svg {
    width: 35px;
    height: 35px;
    fill: none;
    stroke-width: 2.5;
}

.logo img {
    height: 48px;
    width: auto;
    object-fit: contain;
    display: block;
    transition: transform var(--transition-speed);
}

.logo img:hover {
    transform: scale(1.04);
}

nav {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-links {
    display: flex;
    gap: 24px;
}

.nav-link {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    position: relative;
    padding: 8px 0;
    transition: color var(--transition-speed);
}

.nav-link:hover, .nav-link.active {
    color: var(--color-primary);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    transition: width var(--transition-speed);
}

.nav-link:hover::after, .nav-link.active::after {
    width: 100%;
}

/* Action Buttons Header */
.nav-actions {
    display: flex;
    align-items: center;
    gap: 16px;
}

/* Theme Toggle Button */
.theme-toggle {
    background-color: var(--bg-tertiary);
    width: 44px;
    height: 44px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    color: var(--text-secondary);
    font-size: 18px;
    border: 1px solid var(--border-color);
}

.theme-toggle:hover {
    color: var(--color-primary);
    background-color: var(--color-primary-light);
    transform: scale(1.05);
}

.theme-toggle .sun-icon {
    display: none;
}

[data-theme="dark"] .theme-toggle .moon-icon {
    display: none;
}

[data-theme="dark"] .theme-toggle .sun-icon {
    display: block;
}

.btn-header {
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-hover));
    color: white;
    padding: 10px 20px;
    border-radius: 30px;
    font-size: 14px;
    font-weight: 600;
    box-shadow: 0 4px 14px var(--glow-primary);
}

.btn-header:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px var(--glow-primary);
}

/* Menu Hamburger Mobile */
.menu-btn {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 30px;
    height: 20px;
    background: transparent;
    z-index: 1001;
}

.menu-btn span {
    width: 100%;
    height: 3px;
    background-color: var(--text-primary);
    border-radius: 3px;
    transition: all var(--transition-speed) ease;
}

.menu-btn.active span:nth-child(1) {
    transform: translateY(8px) rotate(45deg);
}

.menu-btn.active span:nth-child(2) {
    opacity: 0;
}

.menu-btn.active span:nth-child(3) {
    transform: translateY(-9px) rotate(-45deg);
}

/* ==========================================
   5. HERO SECTION
   ========================================== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 140px;
    padding-bottom: 80px;
    background-image: radial-gradient(circle at 10% 20%, rgba(37, 99, 235, 0.05) 0%, transparent 40%),
                      radial-gradient(circle at 90% 80%, rgba(16, 185, 129, 0.05) 0%, transparent 40%);
}

.hero-grid {
    display: grid;
    grid-template-columns: 1.1fr 0.9fr;
    gap: 40px;
    align-items: center;
}

.hero-badge {
    background-color: var(--color-primary-light);
    color: var(--color-primary);
    padding: 8px 16px;
    border-radius: 50px;
    font-size: 13px;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 24px;
    border: 1px solid rgba(37, 99, 235, 0.15);
}

.hero-badge span.pulse-dot {
    width: 8px;
    height: 8px;
    background-color: var(--color-primary);
    border-radius: 50%;
    animation: pulse-dot 1.5s infinite;
}

@keyframes pulse-dot {
    0% { transform: scale(0.8); opacity: 0.5; }
    50% { transform: scale(1.2); opacity: 1; }
    100% { transform: scale(0.8); opacity: 0.5; }
}

.hero-title {
    font-size: 48px;
    line-height: 1.15;
    margin-bottom: 20px;
    color: var(--text-primary);
}

.hero-subtitle {
    font-size: 16px;
    color: var(--text-secondary);
    margin-bottom: 36px;
    max-width: 580px;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 16px;
    margin-bottom: 48px;
}

.btn-cta {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 14px 28px;
    border-radius: 30px;
    font-size: 15px;
    font-weight: 600;
    box-shadow: 0 10px 20px -5px rgba(0, 0, 0, 0.1);
}

.btn-cta-primary {
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-hover));
    color: white;
    box-shadow: 0 8px 24px var(--glow-primary);
}

.btn-cta-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 30px var(--glow-primary);
}

.btn-cta-secondary {
    background: linear-gradient(135deg, var(--color-secondary), var(--color-secondary-hover));
    color: white;
    box-shadow: 0 8px 24px var(--glow-secondary);
}

.btn-cta-secondary:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 30px var(--glow-secondary);
}

.btn-cta-tertiary {
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-cta-tertiary:hover {
    transform: translateY(-3px);
    background-color: var(--bg-tertiary);
}

/* Hero Illustration Right */
.hero-illustration {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
}

.hero-illustration-container {
    width: 100%;
    max-width: 450px;
    height: auto;
    position: relative;
}

.hero-banners-container {
    position: relative;
    width: 100%;
    height: 380px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.banner-laptop {
    width: 85%;
    height: auto;
    object-fit: contain;
    z-index: 1;
    filter: drop-shadow(0 20px 40px rgba(0, 0, 0, 0.15));
}

.banner-phone {
    position: absolute;
    width: 32%;
    height: auto;
    object-fit: contain;
    bottom: 5px;
    right: 5px;
    z-index: 2;
    filter: drop-shadow(0 20px 30px rgba(0, 0, 0, 0.2));
}

/* Floating elements animations */
.float-laptop {
    animation: floatLaptop 6s ease-in-out infinite;
}

.float-phone {
    animation: floatPhone 5s ease-in-out infinite;
}

@keyframes floatLaptop {
    0% { transform: translateY(0px) rotate(0deg); }
    50% { transform: translateY(-10px) rotate(0.5deg); }
    100% { transform: translateY(0px) rotate(0deg); }
}

@keyframes floatPhone {
    0% { transform: translateY(0px) rotate(0deg); }
    50% { transform: translateY(-15px) rotate(-1deg); }
    100% { transform: translateY(0px) rotate(0deg); }
}

.float-el {
    animation: float-slow 4s ease-in-out infinite;
}

.float-el-fast {
    animation: float-fast 3s ease-in-out infinite;
}

.float-el-delay-1 {
    animation: float-slow 4.5s ease-in-out 0.5s infinite;
}

.float-el-delay-2 {
    animation: float-fast 3.5s ease-in-out 1s infinite;
}

@keyframes float-slow {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-15px); }
}

@keyframes float-fast {
    0%, 100% { transform: translateY(0) scale(1); }
    50% { transform: translateY(-8px) scale(1.05); }
}

/* ==========================================
   6. SECTION TENTANG GAME
   ========================================== */
.about {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.section-header {
    margin-bottom: 24px;
}

.section-tag {
    color: var(--color-primary);
    font-size: 14px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    display: block;
    margin-bottom: 10px;
}

.section-title {
    font-size: 36px;
    color: var(--text-primary);
    line-height: 1.25;
}

.about-description {
    color: var(--text-secondary);
    font-size: 16px;
    margin-bottom: 30px;
    line-height: 1.7;
}

.about-list {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.about-item {
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 500;
    color: var(--text-primary);
}

.about-item svg {
    width: 22px;
    height: 22px;
    fill: none;
    stroke: var(--color-secondary);
    stroke-width: 2.5;
}

.about-media {
    position: relative;
    border-radius: var(--border-radius);
    overflow: visible;
    box-shadow: var(--card-shadow);
    border: 1px solid var(--glass-border);
    aspect-ratio: 16/10;
    background-color: var(--bg-primary);
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.about-banners-container {
    position: relative;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
}

.about-banner-laptop {
    width: 85%;
    height: auto;
    object-fit: contain;
    z-index: 1;
    filter: drop-shadow(0 20px 40px rgba(0, 0, 0, 0.15));
}

.about-banner-phone {
    position: absolute;
    width: 32%;
    height: auto;
    object-fit: contain;
    bottom: -15px;
    right: -10px;
    z-index: 2;
    filter: drop-shadow(0 20px 30px rgba(0, 0, 0, 0.2));
}

/* ==========================================
   7. SECTION FITUR
   ========================================== */
.features {
    background-color: var(--bg-primary);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-top: 60px;
}

.feature-card {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 32px 24px;
    transition: all var(--transition-speed) cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    opacity: 0;
    transition: opacity var(--transition-speed);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--card-shadow);
    border-color: transparent;
}

.feature-card:hover::before {
    opacity: 1;
}

.feature-icon-wrapper {
    width: 50px;
    height: 50px;
    border-radius: 12px;
    background-color: var(--color-primary-light);
    display: flex;
    justify-content: center;
    align-items: center;
    color: var(--color-primary);
    transition: all var(--transition-speed);
}

.feature-card:hover .feature-icon-wrapper {
    background-color: var(--color-primary);
    color: white;
    transform: scale(1.1);
}

.feature-card:nth-child(even) .feature-icon-wrapper {
    background-color: var(--color-secondary-light);
    color: var(--color-secondary);
}

.feature-card:nth-child(even):hover .feature-icon-wrapper {
    background-color: var(--color-secondary);
    color: white;
}

.feature-title {
    font-size: 18px;
    font-weight: 700;
    color: var(--text-primary);
}

.feature-desc {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ==========================================
   8. SECTION LEVEL GAME
   ========================================== */
.levels {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

.levels-container {
    display: flex;
    flex-direction: column;
    gap: 40px;
    margin-top: 60px;
    max-width: 1000px;
    margin-left: auto;
    margin-right: auto;
}

.levels-timeline {
    position: relative;
    padding-bottom: 24px;
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 24px;
}

.levels-timeline::before {
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    width: 100%;
    height: 4px;
    background-color: var(--border-color);
    border-radius: 2px;
}

/* Active Timeline progress line */
.levels-progress-line {
    position: absolute;
    left: 0;
    bottom: 0;
    height: 4px;
    width: 0;
    background: linear-gradient(to right, var(--color-primary), var(--color-secondary));
    transition: width 0.6s ease;
    z-index: 1;
    border-radius: 2px;
}

.level-node {
    position: relative;
    cursor: pointer;
    padding: 24px;
    border-radius: var(--border-radius);
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    transition: all var(--transition-speed) cubic-bezier(0.4, 0, 0.2, 1);
    text-align: left;
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    margin-bottom: 12px;
}

.level-node:hover {
    background-color: var(--bg-primary);
    transform: translateY(-4px);
    box-shadow: var(--card-shadow);
}

.level-node.active:nth-child(2),
.level-node.active:nth-child(3) {
    border-color: var(--color-primary);
    box-shadow: 0 10px 25px -5px rgba(37, 99, 235, 0.08);
}

.level-node.active:nth-child(4) {
    border-color: var(--color-secondary);
    box-shadow: 0 10px 25px -5px rgba(16, 185, 129, 0.08);
}

.level-bullet {
    position: absolute;
    left: 50%;
    bottom: -25px;
    transform: translateX(-50%);
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background-color: var(--bg-secondary);
    border: 3px solid var(--border-color);
    z-index: 2;
    transition: all 0.4s ease;
}

.level-node.active:nth-child(2) .level-bullet,
.level-node.active:nth-child(3) .level-bullet {
    border-color: var(--color-primary);
    background-color: var(--color-primary);
    box-shadow: 0 0 10px var(--color-primary);
}

.level-node.active:nth-child(4) .level-bullet {
    border-color: var(--color-secondary);
    background-color: var(--color-secondary);
    box-shadow: 0 0 10px var(--color-secondary);
}

.level-node-tag {
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 6px;
}

.level-node:nth-child(2) .level-node-tag,
.level-node:nth-child(3) .level-node-tag {
    color: var(--color-primary);
}

.level-node:nth-child(4) .level-node-tag {
    color: var(--color-secondary);
}

.level-node-title {
    font-size: 18px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.level-node-preview {
    font-size: 13px;
    color: var(--text-secondary);
    line-height: 1.5;
}

/* Level Preview Screen Full Page Width */
.level-display {
    background-color: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 40px;
    min-height: 480px;
    position: relative;
    overflow: hidden;
    display: grid;
    grid-template-columns: 1fr;
    box-shadow: var(--card-shadow);
}

.level-detail-panel {
    grid-area: 1 / 1 / 2 / 2;
    opacity: 0;
    visibility: hidden;
    transform: translateY(15px);
    transition: opacity 0.2s ease, transform 0.2s ease, visibility 0.2s ease;
    display: flex;
    flex-direction: column;
    gap: 32px;
    pointer-events: none;
}

.level-detail-panel.active {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
    pointer-events: all;
}

.level-info-top {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 40px;
    align-items: start;
    text-align: left;
}

.level-info-top h3 {
    font-size: 26px;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.level-info-top p {
    color: var(--text-secondary);
    font-size: 15px;
    margin-bottom: 0;
}

.level-topics {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.level-topic-item {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    padding: 12px 16px;
    border-radius: 10px;
    font-size: 14px;
    font-weight: 500;
    display: flex;
    align-items: flex-start;
    gap: 12px;
}

.level-topic-item svg {
    width: 18px;
    height: 18px;
    fill: none;
    stroke-width: 2.5;
    margin-top: 2px;
    flex-shrink: 0;
}

.level-visual-preview {
    border-radius: 12px;
    border: 1px solid var(--border-color);
    overflow: hidden;
    background-color: #000;
    box-shadow: var(--card-shadow);
    width: 100%;
    aspect-ratio: 16 / 9;
    max-height: 500px;
    height: auto;
    display: flex;
    justify-content: center;
    align-items: center;
}

.level-visual-preview video {
    width: 100%;
    height: 100%;
    object-fit: contain;
    background: #000;
}

@media (max-width: 768px) {
    .levels-timeline {
        grid-template-columns: 1fr;
        gap: 16px;
        padding-bottom: 0;
    }
    .levels-timeline::before, .levels-progress-line, .level-bullet {
        display: none;
    }
    .level-node {
        margin-bottom: 0;
    }
    .level-info-top {
        grid-template-columns: 1fr;
        gap: 24px;
    }
    .level-topics {
        grid-template-columns: 1fr;
    }
}

.level-visual-preview svg {
    height: 80%;
    width: 80%;
}

/* ==========================================
   9. SECTION GAMEPLAY (CAROUSEL SLIDER)
   ========================================== */
.gameplay {
    background-color: var(--bg-primary);
}

/* Gallery Tabs */
.gallery-tabs-container {
    display: flex;
    justify-content: center;
    gap: 16px;
    margin-top: 30px;
    margin-bottom: 45px;
}

.gallery-tab-btn {
    padding: 12px 28px;
    border-radius: 30px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    background-color: var(--bg-secondary);
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
    transition: all var(--transition-speed);
}

.gallery-tab-btn:hover {
    color: var(--color-primary);
    border-color: var(--color-primary-light);
    background-color: var(--color-primary-light);
}

.gallery-tab-btn.active {
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-hover));
    color: white;
    border-color: transparent;
    box-shadow: 0 8px 20px var(--glow-primary);
}

.gallery-tab-content {
    display: none;
}

.gallery-tab-content.active {
    display: block;
    animation: tabFadeIn 0.5s ease;
}

@keyframes tabFadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.gameplay-carousel-container {
    position: relative;
    width: 100%;
    max-width: 1000px;
    margin: 0 auto;
    overflow: hidden;
    border-radius: var(--border-radius);
    box-shadow: var(--card-shadow);
    border: 1px solid var(--border-color);
}

.gameplay-slider {
    display: flex;
    transition: transform 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    width: 100%;
}

.gameplay-slide {
    min-width: 100%;
    aspect-ratio: 16/9;
    position: relative;
    background-color: #0c101d;
    display: flex;
    justify-content: center;
    align-items: center;
}

.gameplay-slide img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

/* Navigation Arrows */
.slider-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background-color: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(8px);
    color: white;
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 10;
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.slider-btn:hover {
    background-color: var(--color-primary);
    border-color: var(--color-primary);
}

.slider-btn-prev {
    left: 20px;
}

.slider-btn-next {
    right: 20px;
}

.slider-dots {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-top: 24px;
}

.slider-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: var(--border-color);
    cursor: pointer;
    transition: all var(--transition-speed);
}

.slider-dot.active {
    background-color: var(--color-primary);
    width: 30px;
    border-radius: 10px;
}

/* ==========================================
   10. SECTION DEMO (INTERACTIVE SIMULATOR)
   ========================================== */
.demo {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

.demo-layout {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 40px;
    margin-top: 60px;
    align-items: stretch;
}

.demo-screen {
    background-color: #0F172A; /* Simulated dark gaming screen */
    border-radius: var(--border-radius);
    border: 6px solid #1E293B;
    box-shadow: var(--card-shadow), 0 0 40px rgba(37, 99, 235, 0.15);
    min-height: 480px;
    position: relative;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    color: white;
}

.demo-header {
    background-color: #1E293B;
    padding: 12px 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid #334155;
}

.demo-title-bar {
    font-size: 14px;
    font-weight: 700;
    color: var(--color-secondary);
    display: flex;
    align-items: center;
    gap: 8px;
}

.demo-status-pills {
    display: flex;
    gap: 12px;
}

.status-pill {
    background-color: #0F172A;
    padding: 4px 10px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 6px;
}

.status-pill span.val {
    color: var(--color-secondary);
}

/* Demo Play Area */
.demo-play-area {
    flex-grow: 1;
    padding: 30px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    position: relative;
}

.game-char-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-grow: 1;
}

/* SVG Avatar inside demo */
.game-char-avatar {
    width: 120px;
    height: 180px;
}

.blood-sugar-display {
    background: rgba(30, 41, 59, 0.7);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: 16px;
    width: 200px;
    text-align: center;
    backdrop-filter: blur(8px);
}

.blood-sugar-val {
    font-size: 32px;
    font-weight: 800;
    font-family: 'Outfit', sans-serif;
    color: var(--color-secondary);
    margin: 4px 0;
    transition: color var(--transition-speed);
}

.blood-sugar-label {
    font-size: 11px;
    color: #94A3B8;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.blood-sugar-status {
    font-size: 12px;
    font-weight: 600;
    background-color: rgba(16, 185, 129, 0.2);
    color: var(--color-secondary);
    padding: 2px 8px;
    border-radius: 4px;
    display: inline-block;
    margin-top: 4px;
}

.game-dialog-box {
    background-color: #1E293B;
    border: 1px solid #334155;
    border-radius: 12px;
    padding: 20px;
    position: relative;
    min-height: 100px;
}

.game-dialog-speaker {
    font-size: 12px;
    font-weight: 700;
    color: var(--color-primary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 6px;
}

.game-dialog-text {
    font-size: 14px;
    color: #E2E8F0;
    line-height: 1.5;
}

.game-choices {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-top: 15px;
}

.choice-btn {
    background-color: #0F172A;
    border: 1px solid #334155;
    color: #E2E8F0;
    padding: 12px 20px;
    border-radius: 8px;
    text-align: left;
    font-size: 14px;
    font-weight: 500;
    width: 100%;
}

.choice-btn:hover {
    background-color: var(--color-primary);
    border-color: var(--color-primary);
    color: white;
    transform: translateX(4px);
}

/* Demo Sidebar Controls */
.demo-sidebar {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    padding: 40px;
    background-color: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
}

.demo-sidebar-top h3 {
    font-size: 24px;
    margin-bottom: 16px;
    color: var(--text-primary);
}

.demo-sidebar-top p {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 24px;
    line-height: 1.6;
}

.demo-features-check {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-bottom: 30px;
}

.demo-check-item {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-primary);
}

.demo-check-item svg {
    width: 18px;
    height: 18px;
    stroke: var(--color-primary);
    stroke-width: 3;
    fill: none;
}

.demo-actions-grid {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

/* ==========================================
   11. SECTION DOWNLOAD
   ========================================== */
.download {
    background-color: var(--bg-primary);
    position: relative;
}

.download-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-top: 60px;
}

.download-card {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 40px 30px;
    text-align: center;
    transition: all var(--transition-speed) cubic-bezier(0.4, 0, 0.2, 1);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: space-between;
    min-height: 380px;
}

.download-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--card-shadow);
    border-color: transparent;
}

.download-icon {
    width: 70px;
    height: 70px;
    border-radius: 20px;
    background-color: var(--color-primary-light);
    color: var(--color-primary);
    display: flex;
    justify-content: center;
    align-items: center;
    margin-bottom: 24px;
    transition: all var(--transition-speed);
}

.download-card:hover .download-icon {
    transform: scale(1.1) rotate(5deg);
    background-color: var(--color-primary);
    color: white;
}

.download-card:nth-child(2) .download-icon {
    background-color: var(--color-secondary-light);
    color: var(--color-secondary);
}

.download-card:nth-child(2):hover .download-icon {
    background-color: var(--color-secondary);
    color: white;
}

.download-card:nth-child(3) .download-icon {
    background-color: rgba(245, 158, 11, 0.1);
    color: var(--color-accent);
}

.download-card:nth-child(3):hover .download-icon {
    background-color: var(--color-accent);
    color: white;
}

.download-platform {
    font-size: 22px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.download-specs {
    display: flex;
    flex-direction: column;
    gap: 6px;
    margin-bottom: 30px;
    color: var(--text-secondary);
    font-size: 14px;
}

.download-specs span strong {
    color: var(--text-primary);
}

.btn-download {
    width: 100%;
    padding: 12px 24px;
    border-radius: 30px;
    font-size: 14px;
    font-weight: 600;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 10px;
}

.download-card:nth-child(1) .btn-download {
    background-color: var(--color-primary);
    color: white;
}

.download-card:nth-child(1) .btn-download:hover {
    background-color: var(--color-primary-hover);
}

.download-card:nth-child(2) .btn-download {
    background-color: var(--color-secondary);
    color: white;
}

.download-card:nth-child(2) .btn-download:hover {
    background-color: var(--color-secondary-hover);
}

.download-card:nth-child(3) .btn-download {
    background-color: var(--text-primary);
    color: var(--bg-secondary);
}

.download-card:nth-child(3) .btn-download:hover {
    opacity: 0.9;
}

/* ==========================================
   12. SECTION VIDEO TRAILER
   ========================================== */
.trailer {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

.trailer-wrapper {
    max-width: 900px;
    margin: 60px auto 0;
    position: relative;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--card-shadow);
    aspect-ratio: 16/9;
    background-color: #0F172A;
    border: 1px solid var(--border-color);
}

.trailer-thumbnail {
    width: 100%;
    height: 100%;
    position: relative;
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
}

.trailer-thumbnail svg.thumbnail-art {
    width: 100%;
    height: 100%;
}

.play-btn-overlay {
    position: absolute;
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background-color: var(--color-primary);
    color: white;
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: 0 0 30px var(--color-primary);
    transition: all var(--transition-speed);
    z-index: 5;
}

.trailer-thumbnail:hover .play-btn-overlay {
    transform: scale(1.1);
    background-color: var(--color-secondary);
    box-shadow: 0 0 35px var(--color-secondary);
}

.play-btn-overlay svg {
    width: 30px;
    height: 30px;
    fill: currentColor;
    transform: translateX(2px);
}

/* Video Modal Player (Youtube Support) */
.video-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(10px);
    z-index: 2000;
    display: flex;
    justify-content: center;
    align-items: center;
    opacity: 0;
    visibility: hidden;
    transition: all 0.4s ease;
}

.video-modal.active {
    opacity: 1;
    visibility: visible;
}

.video-modal-content {
    width: 90%;
    max-width: 880px;
    aspect-ratio: 16/9;
    position: relative;
    background-color: #000;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 20px 50px rgba(0,0,0,0.5);
    transform: scale(0.9);
    transition: transform 0.4s ease;
}

.video-modal.active .video-modal-content {
    transform: scale(1);
}

.video-modal-content iframe {
    width: 100%;
    height: 100%;
    border: none;
}

.close-modal-btn {
    position: absolute;
    top: -50px;
    right: 0;
    background: transparent;
    color: white;
    font-size: 28px;
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 600;
}

.close-modal-btn:hover {
    color: var(--color-secondary);
}

/* ==========================================
   13. SECTION PENELITIAN (ACADEMIC)
   ========================================== */
.research {
    background-color: var(--bg-primary);
}

.research-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    margin-top: 60px;
    align-items: start;
}

.research-details {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.research-title-block h3 {
    font-size: 24px;
    line-height: 1.35;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.research-meta {
    display: flex;
    gap: 16px;
    font-size: 13px;
    color: var(--text-tertiary);
    font-weight: 500;
}

.research-meta span {
    background-color: var(--bg-secondary);
    padding: 4px 10px;
    border-radius: 4px;
    border: 1px solid var(--border-color);
}

.research-card {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 30px;
    box-shadow: var(--card-shadow);
}

.research-card-title {
    font-size: 18px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    gap: 10px;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 12px;
}

.research-card-title svg {
    width: 22px;
    height: 22px;
    stroke: var(--color-primary);
    fill: none;
    stroke-width: 2;
}

.research-card:nth-child(2) .research-card-title svg {
    stroke: var(--color-secondary);
}

.research-card-list {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.research-card-list li {
    font-size: 14px;
    color: var(--text-secondary);
    position: relative;
    padding-left: 20px;
    line-height: 1.5;
}

.research-card-list li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--color-primary);
    font-size: 20px;
    top: -2px;
}

.research-card:nth-child(2) .research-card-list li::before {
    color: var(--color-secondary);
}

.citation-box {
    background-color: var(--color-primary-light);
    border-left: 4px solid var(--color-primary);
    padding: 20px;
    border-radius: 0 12px 12px 0;
    font-size: 13px;
    color: var(--text-secondary);
    font-style: italic;
    margin-top: 20px;
}

/* ==========================================
   14. SECTION GALERI (MASONRY)
   ========================================== */
.gallery {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

.gallery-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-top: 60px;
}

.gallery-item {
    position: relative;
    border-radius: var(--border-radius);
    overflow: hidden;
    aspect-ratio: 4/3;
    cursor: pointer;
    box-shadow: var(--card-shadow);
    border: 1px solid var(--border-color);
}

/* Masonry item sizes */
.gallery-item.wide {
    grid-column: span 2;
    aspect-ratio: 8/3;
}

.gallery-item svg {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.gallery-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to top, rgba(15, 23, 42, 0.9), rgba(15, 23, 42, 0.3) 60%, transparent);
    opacity: 0;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    padding: 24px;
    transition: opacity var(--transition-speed);
}

.gallery-item:hover svg {
    transform: scale(1.05);
}

.gallery-item:hover .gallery-overlay {
    opacity: 1;
}

.gallery-overlay h4 {
    color: white;
    font-size: 18px;
    margin-bottom: 4px;
}

.gallery-overlay p {
    color: #94A3B8;
    font-size: 12px;
    font-weight: 500;
}

/* Lightbox Container */
.lightbox {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(10px);
    z-index: 2100;
    display: flex;
    justify-content: center;
    align-items: center;
    opacity: 0;
    visibility: hidden;
    transition: all 0.4s ease;
}

.lightbox.active {
    opacity: 1;
    visibility: visible;
}

.lightbox-content {
    width: 90%;
    max-width: 800px;
    position: relative;
    transform: scale(0.9);
    transition: transform 0.4s ease;
}

.lightbox.active .lightbox-content {
    transform: scale(1);
}

.lightbox-content svg {
    width: 100%;
    height: auto;
    border-radius: var(--border-radius);
    box-shadow: 0 20px 50px rgba(0,0,0,0.5);
    background-color: var(--bg-secondary);
}

.close-lightbox-btn {
    position: absolute;
    top: -40px;
    right: 0;
    color: white;
    font-size: 24px;
    font-weight: 600;
}

.close-lightbox-btn:hover {
    color: var(--color-secondary);
}

/* ==========================================
   15. SECTION TESTIMONI
   ========================================== */
.testimonials {
    background-color: var(--bg-primary);
}

.testimonials-carousel {
    position: relative;
    max-width: 800px;
    margin: 60px auto 0;
    overflow: hidden;
    padding: 20px;
}

.testimonials-slider {
    display: flex;
    transition: transform 0.5s ease;
}

.testimonial-card {
    min-width: 100%;
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 48px;
    box-shadow: var(--card-shadow);
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 24px;
}

.testi-avatar {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    overflow: hidden;
    background-color: var(--bg-primary);
    border: 3px solid var(--color-primary);
}

.testi-avatar svg {
    width: 100%;
    height: 100%;
}

.testimonial-card:nth-child(even) .testi-avatar {
    border-color: var(--color-secondary);
}

.testi-quote {
    font-size: 18px;
    color: var(--text-secondary);
    font-style: italic;
    line-height: 1.6;
}

.testi-author {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.testi-name {
    font-size: 16px;
    font-weight: 700;
    color: var(--text-primary);
}

.testi-role {
    font-size: 13px;
    color: var(--text-tertiary);
    font-weight: 600;
}

.testi-stars {
    display: flex;
    gap: 4px;
    color: var(--color-accent);
}

.testi-stars svg {
    width: 18px;
    height: 18px;
    fill: currentColor;
}

.testi-dots {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-top: 30px;
}

.testi-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: var(--border-color);
    cursor: pointer;
    transition: all var(--transition-speed);
}

.testi-dot.active {
    background-color: var(--color-primary);
    width: 25px;
    border-radius: 10px;
}

/* ==========================================
   16. SECTION FAQ (ACCORDION)
   ========================================== */
.faq {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

.faq-list {
    max-width: 800px;
    margin: 60px auto 0;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.faq-item {
    background-color: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    overflow: hidden;
    transition: all var(--transition-speed);
}

.faq-item:hover {
    border-color: var(--color-primary);
}

.faq-question {
    width: 100%;
    padding: 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 16px;
    font-weight: 700;
    color: var(--text-primary);
    text-align: left;
    background: transparent;
}

.faq-question svg {
    width: 20px;
    height: 20px;
    stroke-width: 2.5;
    transition: transform var(--transition-speed) ease;
}

.faq-item.active .faq-question svg {
    transform: rotate(180deg);
    stroke: var(--color-primary);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.faq-answer-content {
    padding: 0 24px 24px;
    color: var(--text-secondary);
    font-size: 15px;
    line-height: 1.6;
}

/* ==========================================
   17. SECTION TIM PENGEMBANG
   ========================================== */
.team {
    background-color: var(--bg-primary);
}

.team-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-top: 60px;
}

.team-card {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 30px 24px;
    text-align: center;
    transition: all var(--transition-speed);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
}

.team-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--card-shadow);
    border-color: var(--color-primary);
}

.team-photo {
    width: 110px;
    height: 110px;
    border-radius: 50%;
    overflow: hidden;
    background-color: var(--bg-primary);
    border: 4px solid var(--border-color);
    transition: all var(--transition-speed);
}

.team-card:hover .team-photo {
    border-color: var(--color-primary);
    transform: scale(1.05);
}

.team-photo svg {
    width: 100%;
    height: 100%;
}

.team-name {
    font-size: 18px;
    font-weight: 700;
    color: var(--text-primary);
}

.team-position {
    font-size: 13px;
    font-weight: 600;
    color: var(--color-primary);
    background-color: var(--color-primary-light);
    padding: 4px 12px;
    border-radius: 20px;
}

.team-card:nth-child(even) .team-position {
    color: var(--color-secondary);
    background-color: var(--color-secondary-light);
}

.team-inst {
    font-size: 12px;
    color: var(--text-tertiary);
    font-weight: 500;
}

/* ==========================================
   18. FOOTER
   ========================================== */
footer {
    background-color: #0F172A;
    color: #94A3B8;
    padding: 80px 0 30px;
    border-top: 1px solid #1E293B;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr;
    gap: 60px;
    margin-bottom: 50px;
}

.footer-logo {
    color: white;
    margin-bottom: 20px;
}

.footer-logo img {
    max-width: 120px;
    height: auto;
}

.footer-desc {
    font-size: 14px;
    line-height: 1.6;
    margin-bottom: 24px;
    max-width: 320px;
}

.footer-socials {
    display: flex;
    gap: 12px;
}

.social-link {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background-color: #1E293B;
    display: flex;
    justify-content: center;
    align-items: center;
    color: white;
    transition: all var(--transition-speed);
}

.social-link:hover {
    background-color: var(--color-primary);
    transform: translateY(-3px);
}

.footer-title {
    color: white;
    font-size: 16px;
    font-weight: 700;
    margin-bottom: 20px;
}

.footer-links {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.footer-link {
    font-size: 14px;
    transition: color var(--transition-speed);
}

.footer-link:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid #1E293B;
    padding-top: 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 13px;
}

/* Back to top button */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 44px;
    height: 44px;
    background-color: var(--color-primary);
    color: white;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    z-index: 100;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-speed);
}

.back-to-top.active {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background-color: var(--color-secondary);
    transform: translateY(-5px);
}

/* ==========================================
   19. RESPONSIVE DESIGN (MEDIA QUERIES)
   ========================================== */
@media (max-width: 1024px) {
    .hero-grid {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 50px;
    }

    .hero-title {
        font-size: 40px;
    }

    .hero-subtitle {
        margin-left: auto;
        margin-right: auto;
    }

    .hero-actions {
        justify-content: center;
    }

    .hero-illustration {
        order: -1;
    }

    .about-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .about-media {
        order: -1;
    }

    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .levels-container {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .demo-layout {
        grid-template-columns: 1fr;
    }

    .download-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .download-card:nth-child(3) {
        grid-column: span 2;
    }

    .gallery-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .gallery-item.wide {
        grid-column: span 1;
        aspect-ratio: 4/3;
    }

    .research-grid {
        grid-template-columns: 1fr;
    }

    .team-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }
}

@media (max-width: 768px) {
    section {
        padding: 60px 0;
    }

    .nav-links {
        display: none;
        position: fixed;
        top: 70px;
        left: 0;
        width: 100vw;
        height: calc(100vh - 70px);
        background-color: var(--bg-secondary);
        flex-direction: column;
        padding: 40px 24px;
        gap: 20px;
        border-top: 1px solid var(--border-color);
        box-shadow: 0 10px 30px rgba(0,0,0,0.05);
    }

    .nav-links.active {
        display: flex;
    }

    .menu-btn {
        display: flex;
    }

    .nav-actions {
        margin-right: 16px;
    }

    .hero-title {
        font-size: 32px;
    }

    .features-grid {
        grid-template-columns: 1fr;
    }

    .download-grid {
        grid-template-columns: 1fr;
    }

    .download-card:nth-child(3) {
        grid-column: span 1;
    }

    .gallery-grid {
        grid-template-columns: 1fr;
    }

    .team-grid {
        grid-template-columns: 1fr;
    }

    .testimonial-card {
        padding: 30px 20px;
    }

    .levels-timeline {
        padding-left: 20px;
    }

    .level-visual-preview {
        height: 120px;
    }
}

/* ==========================================
   20. SCROLL ANIMATION EFFECTS
   ========================================== */
.reveal {
    opacity: 0;
    transform: translateY(40px);
    transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1), 
                transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.reveal.active {
    opacity: 1;
    transform: translateY(0);
}

.reveal-delay-1 {
    transition-delay: 0.15s;
}

.reveal-delay-2 {
    transition-delay: 0.3s;
}

.reveal-delay-3 {
    transition-delay: 0.45s;
}

/* Simple helper utility */
.text-center {
    text-align: center;
}

.mx-auto {
    margin-left: auto;
    margin-right: auto;
}

/* ==========================================
   21. MATERI READER PAGE
   ========================================== */
.materi-section {
    padding-top: 140px;
    padding-bottom: 80px;
    background-color: var(--bg-secondary);
}

.materi-grid {
    display: grid;
    grid-template-columns: 350px 1fr;
    gap: 40px;
    margin-top: 40px;
    align-items: start;
}

@media (max-width: 992px) {
    .materi-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
}

/* ---- Mobile Materi Reader (≤ 768px) ---- */
@media (max-width: 768px) {
    .materi-section {
        padding-top: 100px;
        padding-bottom: 50px;
        overflow-x: hidden;
    }

    .materi-grid {
        gap: 16px;
        margin-top: 20px;
        overflow-x: hidden;
    }

    /* Sidebar compact */
    .materi-sidebar {
        padding: 14px;
        overflow: visible;
    }

    .materi-sidebar-title {
        font-size: 15px;
        margin-bottom: 10px;
        padding-bottom: 8px;
    }

    /* Materi list: horizontal chip bar, scroll internal only */
    .materi-list {
        flex-direction: row;
        flex-wrap: nowrap;
        overflow-x: auto;
        overflow-y: visible;
        gap: 8px;
        padding-bottom: 4px;
        scrollbar-width: none;
        -webkit-overflow-scrolling: touch;
    }

    .materi-list::-webkit-scrollbar {
        display: none;
    }

    /* Compact chip-style buttons */
    .materi-btn {
        flex-direction: row;
        align-items: center;
        gap: 8px;
        padding: 10px 14px;
        min-width: max-content;
        width: auto;
        flex-shrink: 0;
        border-radius: 30px;
    }

    .materi-btn-num {
        width: 28px;
        height: 28px;
        min-width: 28px;
        font-size: 13px;
    }

    .materi-btn-info {
        flex-grow: 0;
        white-space: nowrap;
    }

    .materi-btn-title {
        font-size: 13px;
        margin-bottom: 0;
    }

    .materi-btn-meta {
        display: none; /* sembunyikan subtitle di chip kecil */
    }

    /* Reader panel */
    .materi-reader {
        padding: 14px;
        overflow: hidden;
    }

    .reader-title {
        font-size: 16px;
        margin-bottom: 10px;
    }

    .reader-progress-text-row {
        font-size: 12px;
    }

    /* Frame gambar proporsional */
    .reader-frame {
        aspect-ratio: 4 / 3;
        overflow: hidden;
    }

    /* Tombol navigasi full-width */
    .reader-controls {
        flex-direction: column;
        gap: 8px;
        margin-top: 14px;
    }

    .reader-btn {
        width: 100%;
        padding: 11px 16px;
        text-align: center;
        font-size: 14px;
    }

    /* Thumbnails lebih kecil */
    .reader-thumbnails-title {
        font-size: 12px;
        margin-top: 18px;
    }

    .reader-thumb {
        width: 68px;
        min-width: 68px;
    }
}

/* ---- Small Mobile (≤ 480px) ---- */
@media (max-width: 480px) {
    .materi-section {
        padding-top: 90px;
    }

    .reader-title {
        font-size: 14px;
    }

    .reader-frame {
        aspect-ratio: 1 / 1;
    }

    .materi-btn {
        padding: 8px 12px;
    }

    .materi-btn-num {
        width: 26px;
        height: 26px;
        min-width: 26px;
        font-size: 12px;
    }

    .materi-btn-title {
        font-size: 12px;
    }

    .reader-thumb {
        width: 56px;
        min-width: 56px;
    }
}

.materi-sidebar {
    background-color: var(--bg-primary);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    padding: 24px;
    box-shadow: var(--card-shadow);
}

.materi-sidebar-title {
    font-size: 20px;
    font-family: 'Outfit', sans-serif;
    color: var(--text-primary);
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--border-color);
}

.materi-list {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.materi-btn {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 16px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    background-color: var(--bg-secondary);
    cursor: pointer;
    text-align: left;
    transition: all var(--transition-speed);
    width: 100%;
}

.materi-btn:hover {
    border-color: var(--color-primary-light);
    background-color: var(--color-primary-light);
}

.materi-btn.active {
    border-color: var(--color-primary);
    background-color: rgba(37, 99, 235, 0.05);
    box-shadow: 0 4px 15px rgba(37, 99, 235, 0.1);
}

.materi-btn-num {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 36px;
    height: 36px;
    min-width: 36px;
    border-radius: 50%;
    background-color: var(--border-color);
    color: var(--text-secondary);
    font-weight: 700;
    font-family: 'Outfit', sans-serif;
    transition: all var(--transition-speed);
}

.materi-btn:hover .materi-btn-num {
    background-color: var(--color-primary);
    color: white;
}

.materi-btn.active .materi-btn-num {
    background-color: var(--color-primary);
    color: white;
}

.materi-btn-info {
    flex-grow: 1;
}

.materi-btn-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 4px;
    font-family: 'Outfit', sans-serif;
}

.materi-btn-meta {
    font-size: 12px;
    color: var(--text-secondary);
}

/* Reader Main Content Area */
.materi-reader {
    background-color: var(--bg-primary);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    padding: 30px;
    box-shadow: var(--card-shadow);
}

.reader-header {
    margin-bottom: 24px;
}

.reader-title {
    font-size: 24px;
    font-family: 'Outfit', sans-serif;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.reader-progress-container {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.reader-progress-text-row {
    display: flex;
    justify-content: space-between;
    font-size: 14px;
    color: var(--text-secondary);
}

.reader-progress-bar {
    width: 100%;
    height: 6px;
    background-color: var(--border-color);
    border-radius: 3px;
    overflow: hidden;
}

.reader-progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    width: 0%;
    border-radius: 3px;
    transition: width 0.3s ease;
}

/* Image Frame Viewport */
.reader-frame {
    width: 100%;
    aspect-ratio: 3 / 2;
    border-radius: var(--border-radius);
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    overflow: hidden;
    position: relative;
    box-shadow: var(--card-shadow);
}

.reader-image {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: contain;
    display: block;
    transition: opacity 0.2s ease;
}

/* Overlay Navigation Arrows (on top of image frame) */
.frame-nav-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    z-index: 10;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: rgba(15, 23, 42, 0.65);
    backdrop-filter: blur(6px);
    border: 1px solid rgba(255,255,255,0.15);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-speed);
    box-shadow: 0 4px 12px rgba(0,0,0,0.3);
}

.frame-nav-btn:hover:not(:disabled) {
    background: var(--color-primary);
    border-color: var(--color-primary);
    transform: translateY(-50%) scale(1.1);
}

.frame-nav-btn:disabled {
    opacity: 0.25;
    cursor: not-allowed;
}

.frame-nav-prev {
    left: 12px;
}

.frame-nav-next {
    right: 12px;
}

/* Page badge bottom-center of image */
.frame-page-badge {
    position: absolute;
    bottom: 12px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(15, 23, 42, 0.7);
    backdrop-filter: blur(6px);
    color: white;
    font-size: 12px;
    font-weight: 600;
    padding: 4px 12px;
    border-radius: 20px;
    border: 1px solid rgba(255,255,255,0.15);
    z-index: 10;
    white-space: nowrap;
    pointer-events: none;
}

.reader-controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 24px;
    gap: 20px;
}

.reader-btn {
    padding: 12px 24px;
    border-radius: 30px;
    font-weight: 600;
    font-size: 14px;
    cursor: pointer;
    transition: all var(--transition-speed);
}

.reader-btn-prev {
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.reader-btn-prev:hover:not(:disabled) {
    background-color: var(--border-color);
}

.reader-btn-next {
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-hover));
    color: white;
    border: none;
    box-shadow: 0 4px 12px var(--glow-primary);
}

.reader-btn-next:hover:not(:disabled) {
    box-shadow: 0 6px 18px var(--glow-primary);
    transform: translateY(-1px);
}

.reader-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none !important;
    box-shadow: none !important;
}

/* Page Thumbnails */
.reader-thumbnails-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-top: 30px;
    margin-bottom: 12px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.reader-thumbnails-grid {
    display: flex;
    gap: 12px;
    overflow-x: auto;
    padding-bottom: 10px;
    scrollbar-width: thin;
    scrollbar-color: var(--border-color) transparent;
}

.reader-thumbnails-grid::-webkit-scrollbar {
    height: 6px;
}

.reader-thumbnails-grid::-webkit-scrollbar-thumb {
    background-color: var(--border-color);
    border-radius: 3px;
}

.reader-thumb {
    width: 100px;
    min-width: 100px;
    aspect-ratio: 16/9;
    border-radius: 6px;
    overflow: hidden;
    border: 2px solid var(--border-color);
    cursor: pointer;
    background-color: #0c101d;
    transition: all var(--transition-speed);
    opacity: 0.6;
}

.reader-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.reader-thumb:hover {
    opacity: 0.9;
    border-color: var(--color-primary-light);
}

.reader-thumb.active {
    opacity: 1;
    border-color: var(--color-primary);
    box-shadow: 0 0 10px var(--glow-primary);
}

/* ==========================================
   22. FLASHCARD SIMULASI
   ========================================== */
.flashcard-section {
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    padding: 100px 0;
    border-top: 1px solid var(--border-color);
}

.fc-arena {
    margin-top: 50px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 24px;
}

/* Top bar: counter + hint */
.fc-topbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    max-width: 600px;
}

.fc-counter {
    font-size: 15px;
    font-weight: 700;
    color: var(--color-primary);
    font-family: 'Outfit', sans-serif;
}

.fc-hint {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 13px;
    color: var(--text-tertiary);
    font-style: italic;
}

/* Stage: nav + card */
.fc-stage {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 20px;
    width: 100%;
}

/* Nav arrow buttons */
.fc-nav-btn {
    width: 52px;
    height: 52px;
    border-radius: 50%;
    background-color: var(--bg-secondary);
    border: 2px solid var(--border-color);
    color: var(--text-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-speed);
    flex-shrink: 0;
    box-shadow: var(--card-shadow);
}

.fc-nav-btn:hover:not(:disabled) {
    background-color: var(--color-primary);
    border-color: var(--color-primary);
    color: white;
    transform: scale(1.08);
    box-shadow: 0 6px 20px var(--glow-primary);
}

.fc-nav-btn:disabled {
    opacity: 0.3;
    cursor: not-allowed;
    transform: none;
}

/* Card wrapper: sets the perspective */
.fc-card-wrap {
    perspective: 1200px;
    cursor: pointer;
    width: 100%;
    max-width: 480px;
    flex-shrink: 1;
}

/* Inner card: handles 3D flip */
.fc-card {
    position: relative;
    width: 100%;
    aspect-ratio: 3 / 2;
    transform-style: preserve-3d;
    transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    border-radius: var(--border-radius);
}

.fc-card.is-flipped {
    transform: rotateY(180deg);
}

/* Both faces share base styles */
.fc-face {
    position: absolute;
    inset: 0;
    border-radius: var(--border-radius);
    overflow: hidden;
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
    box-shadow: 0 20px 50px rgba(0,0,0,0.15);
}

/* Back face: shown by default */
.fc-back {
    transform: rotateY(0deg);
    background-color: transparent;
}

/* Front face: shown after flip */
.fc-front {
    transform: rotateY(180deg);
    background-color: transparent;
}

.fc-img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    display: block;
    background-color: transparent;
}

/* "Tap to open" label on back face */
.fc-back-label {
    position: absolute;
    bottom: 14px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(255,255,255,0.12);
    backdrop-filter: blur(8px);
    color: white;
    font-size: 13px;
    font-weight: 600;
    padding: 6px 18px;
    border-radius: 20px;
    display: flex;
    align-items: center;
    gap: 7px;
    white-space: nowrap;
    border: 1px solid rgba(255,255,255,0.2);
    pointer-events: none;
    animation: pulseHint 2s ease-in-out infinite;
}

@keyframes pulseHint {
    0%, 100% { opacity: 0.8; transform: translateX(-50%) scale(1); }
    50%       { opacity: 1;   transform: translateX(-50%) scale(1.04); }
}

/* Dot indicators */
.fc-dots {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    justify-content: center;
    max-width: 480px;
}

.fc-dot {
    width: 9px;
    height: 9px;
    border-radius: 50%;
    background-color: var(--border-color);
    cursor: pointer;
    transition: all var(--transition-speed);
    border: none;
}

.fc-dot:hover {
    background-color: var(--color-primary-hover);
}

.fc-dot.active {
    background-color: var(--color-primary);
    width: 24px;
    border-radius: 10px;
    box-shadow: 0 0 8px var(--glow-primary);
}

/* Thumbnail strip */
.fc-thumbnails {
    display: flex;
    gap: 10px;
    overflow-x: auto;
    max-width: 600px;
    width: 100%;
    padding-bottom: 6px;
    scrollbar-width: thin;
    scrollbar-color: var(--border-color) transparent;
}

.fc-thumbnails::-webkit-scrollbar { height: 4px; }
.fc-thumbnails::-webkit-scrollbar-thumb {
    background-color: var(--border-color);
    border-radius: 2px;
}

.fc-thumb {
    width: 80px;
    min-width: 80px;
    aspect-ratio: 3/2;
    border-radius: 8px;
    overflow: hidden;
    border: 2px solid var(--border-color);
    cursor: pointer;
    background-color: transparent;
    opacity: 0.55;
    transition: all var(--transition-speed);
    flex-shrink: 0;
}

.fc-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.fc-thumb:hover { opacity: 0.85; border-color: var(--color-primary-light); }
.fc-thumb.active {
    opacity: 1;
    border-color: var(--color-primary);
    box-shadow: 0 0 10px var(--glow-primary);
}

/* ---- Mobile responsive ---- */
@media (max-width: 768px) {
    .flashcard-section { padding: 60px 0; }

    .fc-stage { gap: 10px; }

    .fc-nav-btn {
        width: 42px;
        height: 42px;
    }

    .fc-card-wrap { max-width: 100%; }

    .fc-thumb {
        width: 60px;
        min-width: 60px;
    }

    .fc-topbar { max-width: 100%; }
    .fc-dots   { max-width: 100%; }
    .fc-thumbnails { max-width: 100%; }
}