@import url('https://fonts.googleapis.com/css2?family=Fira+Code:wght@400;500&family=Inter:wght@300;400;500;600;700&family=Orbitron:wght@500;700;900&display=swap');

:root {
    --bg-primary: #08090d;
    --bg-secondary: #10121d;
    --bg-tertiary: #191c2e;
    --accent-purple: #8b5cf6;
    --accent-pink: #ec4899;
    --accent-cyan: #06b6d4;
    --accent-green: #10b981;
    --accent-red: #ef4444;
    --text-main: #f3f4f6;
    --text-muted: #9ca3af;
    --border-color: rgba(255, 255, 255, 0.08);
    
    --neon-purple-glow: 0 0 10px rgba(139, 92, 246, 0.4), 0 0 25px rgba(139, 92, 246, 0.2);
    --neon-pink-glow: 0 0 10px rgba(236, 72, 153, 0.4), 0 0 25px rgba(236, 72, 153, 0.2);
    --neon-cyan-glow: 0 0 10px rgba(6, 182, 212, 0.4), 0 0 25px rgba(6, 182, 212, 0.2);
    
    --glass-bg: rgba(16, 18, 29, 0.85);
    --glass-border: rgba(255, 255, 255, 0.06);
    --glass-blur: blur(16px);
    
    --font-display: 'Orbitron', sans-serif;
    --font-sans: 'Inter', sans-serif;
    --font-code: 'Fira Code', monospace;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    scroll-behavior: smooth;
}

/* Hide default cursor on desktop to display custom cursor */
@media (min-width: 1025px) {
    html, body, button, a, input, select, textarea {
        cursor: none !important;
    }
}

body {
    background-color: var(--bg-primary);
    color: var(--text-main);
    font-family: var(--font-sans);
    line-height: 1.6;
    overflow-x: hidden;
    position: relative;
}

/* Matrix Background Canvas */
canvas#matrix-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -1;
    pointer-events: none;
    opacity: 0.15;
}

/* Custom Interactive Cursor */
.custom-cursor-dot {
    width: 6px;
    height: 6px;
    background: var(--accent-cyan);
    position: fixed;
    pointer-events: none;
    z-index: 10000;
    border-radius: 50%;
    transform: translate(-50%, -50%);
    box-shadow: var(--neon-cyan-glow);
    transition: width 0.15s, height 0.15s, background-color 0.15s;
}

.custom-cursor-glow {
    width: 32px;
    height: 32px;
    border: 2px solid var(--accent-purple);
    position: fixed;
    pointer-events: none;
    z-index: 9999;
    border-radius: 50%;
    transform: translate(-50%, -50%);
    box-shadow: var(--neon-purple-glow);
    transition: width 0.25s, height 0.25s, border-color 0.25s, transform 0.1s ease-out;
}

/* Cursor Hover states */
.custom-cursor-dot.hovered {
    width: 12px;
    height: 12px;
    background: var(--accent-pink);
}

.custom-cursor-glow.hovered {
    width: 48px;
    height: 48px;
    border-color: var(--accent-pink);
    box-shadow: var(--neon-pink-glow);
}

/* Click Ripple Wave */
.click-ripple {
    position: fixed;
    border: 2px solid var(--accent-pink);
    border-radius: 50%;
    pointer-events: none;
    z-index: 9998;
    transform: translate(-50%, -50%);
    animation: rippleAnim 0.6s cubic-bezier(0.1, 0.8, 0.3, 1) forwards;
}

@keyframes rippleAnim {
    0% {
        width: 0px;
        height: 0px;
        opacity: 1;
    }
    100% {
        width: 100px;
        height: 100px;
        opacity: 0;
    }
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}
::-webkit-scrollbar-track {
    background: var(--bg-primary);
}
::-webkit-scrollbar-thumb {
    background: var(--bg-tertiary);
    border-radius: 4px;
    border: 2px solid var(--bg-primary);
}
::-webkit-scrollbar-thumb:hover {
    background: var(--accent-purple);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Page Transition Overlay Sweep */
.transition-sweep {
    position: fixed;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--accent-purple), var(--accent-pink), var(--accent-cyan));
    z-index: 99999;
    pointer-events: none;
}

.transition-sweep.active {
    animation: sweepEffect 1.2s cubic-bezier(0.76, 0, 0.24, 1) forwards;
}

@keyframes sweepEffect {
    0% { left: -100%; }
    50% { left: 0; }
    100% { left: 100%; }
}

/* Header & Navigation */
header {
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border-bottom: 1px solid var(--glass-border);
    position: sticky;
    top: 0;
    z-index: 100;
    height: 70px;
    display: flex;
    align-items: center;
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
}

.logo {
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 900;
    text-transform: uppercase;
    color: var(--text-main);
    display: flex;
    align-items: center;
    gap: 10px;
    text-shadow: var(--neon-cyan-glow);
}

.logo span {
    color: var(--accent-pink);
    text-shadow: var(--neon-pink-glow);
}

.logo i {
    color: var(--accent-cyan);
    animation: rotateLogo 6s linear infinite;
}

@keyframes rotateLogo {
    100% { transform: rotate(360deg); }
}

nav {
    display: flex;
    gap: 10px;
}

.nav-link {
    background: transparent;
    border: none;
    color: var(--text-muted);
    font-family: var(--font-display);
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    padding: 8px 16px;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s;
    position: relative;
    overflow: hidden;
}

.nav-link::before {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--accent-cyan), var(--accent-purple));
    transition: width 0.3s ease;
}

.nav-link:hover {
    color: var(--text-main);
}

.nav-link:hover::before,
.nav-link.active::before {
    width: 80%;
}

.nav-link.active {
    color: var(--accent-cyan);
    text-shadow: var(--neon-cyan-glow);
    background: rgba(6, 182, 212, 0.06);
}

/* Sections Control */
.section {
    display: none;
    padding: 60px 0;
}

.section.active {
    display: block;
    animation: sectionFadeIn 0.8s cubic-bezier(0.25, 1, 0.5, 1) forwards;
}

@keyframes sectionFadeIn {
    from {
        opacity: 0;
        transform: scale(0.97) translateY(15px);
    }
    to {
        opacity: 1;
        transform: scale(1) translateY(0);
    }
}

.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-subtitle {
    font-family: var(--font-display);
    font-size: 0.8rem;
    color: var(--accent-purple);
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 8px;
    display: block;
}

.section-title {
    font-family: var(--font-display);
    font-size: 2.2rem;
    text-transform: uppercase;
    background: linear-gradient(135deg, var(--text-main), #9ca3af);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* HERO SECTION */
.hero {
    position: relative;
    padding: 80px 0;
    display: flex;
    align-items: center;
    background: radial-gradient(circle at 80% 20%, rgba(139, 92, 246, 0.12) 0%, transparent 60%),
                radial-gradient(circle at 15% 80%, rgba(6, 182, 212, 0.1) 0%, transparent 60%);
}

.hero-grid {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 40px;
    align-items: center;
}

.hero-tag {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(6, 182, 212, 0.08);
    color: var(--accent-cyan);
    border: 1px solid rgba(6, 182, 212, 0.15);
    padding: 6px 14px;
    border-radius: 50px;
    font-family: var(--font-display);
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    margin-bottom: 20px;
    box-shadow: 0 0 15px rgba(6, 182, 212, 0.08);
}

.hero-title {
    font-family: var(--font-display);
    font-size: 3.5rem;
    line-height: 1.1;
    font-weight: 900;
    text-transform: uppercase;
    margin-bottom: 20px;
}

.hero-title span {
    background: linear-gradient(135deg, var(--accent-cyan), var(--accent-purple), var(--accent-pink));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    text-shadow: 0 0 20px rgba(139, 92, 246, 0.25);
}

.hero-desc {
    color: var(--text-muted);
    font-size: 1.05rem;
    margin-bottom: 30px;
    max-width: 550px;
}

.hero-buttons {
    display: flex;
    gap: 16px;
}

.btn {
    font-family: var(--font-display);
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    padding: 12px 24px;
    border-radius: 8px;
    border: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

.btn-cyan {
    background: linear-gradient(135deg, var(--accent-cyan), var(--accent-purple));
    color: white;
    box-shadow: var(--neon-cyan-glow);
}

.btn-cyan:hover {
    transform: translateY(-2px);
    box-shadow: 0 0 20px rgba(6, 182, 212, 0.6), 0 0 35px rgba(139, 92, 246, 0.4);
}

.btn-outline {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-main);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.03);
    border-color: var(--accent-purple);
    box-shadow: var(--neon-purple-glow);
}

.hero-graphic {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 20px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5);
    position: relative;
    overflow: hidden;
    /* Enable 3D Tilt perspective context */
    transform-style: preserve-3d;
    perspective: 1000px;
    transition: transform 0.1s ease-out;
}

.hero-graphic::before {
    content: '';
    position: absolute;
    top: 0; left: 0; width: 100%; height: 3px;
    background: linear-gradient(90deg, var(--accent-cyan), var(--accent-purple), var(--accent-pink));
}

.window-header {
    display: flex;
    gap: 6px;
    margin-bottom: 15px;
    transform: translateZ(20px); /* 3D pop effect */
}

.dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
}

.dot-red { background: #ef4444; }
.dot-yellow { background: #f59e0b; }
.dot-green { background: #10b981; }

.code-mock {
    font-family: var(--font-code);
    font-size: 0.8rem;
    color: var(--text-muted);
    transform: translateZ(30px); /* Higher 3D pop effect */
}

.code-mock span.tag { color: var(--accent-pink); }
.code-mock span.attr { color: var(--accent-cyan); }
.code-mock span.val { color: var(--accent-purple); }
.code-mock span.comment { color: #4b5563; }

/* TAB 1: LESSONS ROADMAP */
.roadmap-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 24px;
}

.lesson-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 24px;
    transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    position: relative;
    overflow: hidden;
    transform-style: preserve-3d;
    perspective: 1000px;
}

.lesson-card::before {
    content: '';
    position: absolute;
    top: 0; left: 0; height: 100%; width: 4px;
    background: var(--accent-purple);
    transition: width 0.3s;
}

.lesson-card:hover {
    border-color: rgba(139, 92, 246, 0.3);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.4), var(--neon-purple-glow);
}

.lesson-card:hover::before {
    width: 8px;
}

.lesson-card.completed::after {
    content: '\f058';
    font-family: 'Font Awesome 6 Free';
    font-weight: 900;
    position: absolute;
    top: 20px;
    right: 20px;
    color: var(--accent-green);
    font-size: 1.2rem;
    transform: translateZ(10px);
}

.lesson-icon {
    font-size: 2.2rem;
    margin-bottom: 20px;
    display: inline-block;
    transform: translateZ(25px);
}

.icon-html { color: #f97316; }
.icon-css { color: var(--accent-cyan); }
.icon-js { color: var(--accent-yellow); }
.icon-react { color: #38bdf8; }

.lesson-card h3 {
    font-size: 1.15rem;
    margin-bottom: 8px;
    transform: translateZ(20px);
}

.lesson-card p {
    font-size: 0.85rem;
    color: var(--text-muted);
    transform: translateZ(15px);
}

/* TAB 2: LIVE PLAYGROUND */
.playground-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    height: 600px;
}

.editor-pane {
    display: flex;
    flex-direction: column;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    overflow: hidden;
}

.pane-header {
    background: var(--bg-tertiary);
    padding: 12px 20px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-family: var(--font-display);
    font-size: 0.8rem;
    font-weight: 700;
}

.pane-header i {
    margin-right: 6px;
}

.html-color { color: #f97316; }
.css-color { color: var(--accent-cyan); }

.code-textarea {
    flex-grow: 1;
    width: 100%;
    background: var(--bg-secondary);
    border: none;
    color: #34d399;
    font-family: var(--font-code);
    font-size: 0.85rem;
    padding: 20px;
    resize: none;
    outline: none;
}

.code-textarea:focus {
    background: rgba(255, 255, 255, 0.01);
}

.preview-pane {
    background: white;
    border-radius: 12px;
    border: 4px solid var(--bg-secondary);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

iframe.preview-iframe {
    width: 100%;
    height: 100%;
    border: none;
    background: white;
}

.playground-controls {
    display: flex;
    justify-content: flex-end;
    margin-top: 15px;
    gap: 12px;
}

/* TAB 3: VISUAL CSS GENERATOR */
.generator-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: center;
}

.control-panel {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 30px;
    transform-style: preserve-3d;
    perspective: 1000px;
}

.control-group {
    margin-bottom: 24px;
}

.control-label {
    display: flex;
    justify-content: space-between;
    font-family: var(--font-display);
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--text-muted);
    margin-bottom: 8px;
}

.control-label span.val-label {
    color: var(--accent-cyan);
}

input[type="range"].slider {
    -webkit-appearance: none;
    width: 100%;
    height: 6px;
    border-radius: 5px;
    background: var(--bg-tertiary);
    outline: none;
}

input[type="range"].slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--accent-cyan);
    cursor: pointer;
    box-shadow: var(--neon-cyan-glow);
    transition: transform 0.1s;
}

input[type="range"].slider::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

.color-inputs {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.color-input-box {
    display: flex;
    align-items: center;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 6px 12px;
}

.color-input-box input[type="color"] {
    border: none;
    background: transparent;
    width: 30px;
    height: 30px;
    cursor: pointer;
    margin-right: 10px;
}

.color-input-box span {
    font-family: var(--font-code);
    font-size: 0.8rem;
}

.preview-box-container {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 60px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    position: relative;
    min-height: 380px;
}

.target-box {
    width: 180px;
    height: 180px;
    background: linear-gradient(135deg, var(--accent-purple), var(--accent-pink));
    border-radius: 12px;
    margin-bottom: 40px;
    transition: all 0.1s;
}

.output-code-box {
    width: 100%;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 16px;
    position: relative;
}

.output-code {
    font-family: var(--font-code);
    font-size: 0.8rem;
    color: #10b981;
    white-space: pre-wrap;
    word-break: break-all;
}

.copy-css-btn {
    position: absolute;
    top: 10px;
    right: 10px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    color: var(--accent-cyan);
    padding: 4px 10px;
    border-radius: 4px;
    font-size: 0.75rem;
    cursor: pointer;
    font-family: var(--font-display);
}

.copy-css-btn:hover {
    background: var(--accent-cyan);
    color: black;
}

/* TAB 4: INTERACTIVE QUIZ */
.quiz-wrapper {
    max-width: 650px;
    margin: 0 auto;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 40px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
    position: relative;
}

.quiz-progress-container {
    width: 100%;
    height: 6px;
    background: var(--bg-tertiary);
    border-radius: 5px;
    margin-bottom: 30px;
    overflow: hidden;
}

.quiz-progress-bar {
    width: 0%;
    height: 100%;
    background: linear-gradient(90deg, var(--accent-cyan), var(--accent-purple));
    transition: width 0.3s ease;
}

.quiz-question-number {
    font-family: var(--font-display);
    font-size: 0.8rem;
    color: var(--accent-purple);
    font-weight: 700;
    margin-bottom: 10px;
    text-transform: uppercase;
}

.quiz-question-text {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 30px;
    line-height: 1.4;
}

.quiz-options {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-bottom: 30px;
}

.quiz-option {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    padding: 16px 20px;
    border-radius: 8px;
    color: var(--text-main);
    text-align: left;
    font-size: 0.95rem;
    cursor: pointer;
    transition: all 0.2s;
    outline: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.quiz-option:hover:not(.disabled) {
    border-color: var(--accent-purple);
    background: rgba(139, 92, 246, 0.03);
    transform: translateX(4px);
}

.quiz-option.correct {
    background: rgba(16, 185, 129, 0.1) !important;
    border-color: var(--accent-green) !important;
    color: var(--accent-green) !important;
    font-weight: 600;
}

.quiz-option.incorrect {
    background: rgba(239, 68, 68, 0.1) !important;
    border-color: var(--accent-red) !important;
    color: var(--accent-red) !important;
}

.quiz-option.disabled {
    cursor: not-allowed;
    opacity: 0.8;
}

.quiz-footer {
    display: flex;
    justify-content: flex-end;
}

.quiz-result-view {
    text-align: center;
    padding: 20px 0;
}

.quiz-score-circle {
    width: 140px;
    height: 140px;
    border-radius: 50%;
    border: 6px solid var(--accent-cyan);
    box-shadow: var(--neon-cyan-glow);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    margin: 0 auto 30px;
}

.quiz-score-val {
    font-family: var(--font-display);
    font-size: 2.2rem;
    font-weight: 900;
    color: var(--accent-cyan);
}

.quiz-score-label {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
}

/* Modals */
.modal-overlay {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background: rgba(0, 0, 0, 0.85);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    z-index: 200;
    display: none;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.modal-overlay.active {
    display: flex;
}

.modal-content {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    width: 100%;
    max-width: 600px;
    box-shadow: 0 25px 50px rgba(0, 0, 0, 0.6);
    overflow: hidden;
    position: relative;
    animation: modalSlideUp 0.3s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

@keyframes modalSlideUp {
    from { transform: translateY(40px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

.modal-header {
    background: rgba(255, 255, 255, 0.02);
    padding: 20px 24px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-title {
    font-family: var(--font-display);
    font-size: 1.15rem;
    text-transform: uppercase;
    color: var(--accent-cyan);
}

.modal-close {
    background: transparent;
    border: none;
    color: var(--text-muted);
    font-size: 1.5rem;
    cursor: pointer;
    transition: color 0.2s;
}

.modal-close:hover {
    color: white;
}

.modal-body {
    padding: 24px;
}

.lesson-content {
    font-size: 0.95rem;
    color: var(--text-muted);
}

.lesson-content h4 {
    color: var(--text-main);
    margin: 20px 0 10px;
}

.lesson-content p {
    margin-bottom: 12px;
}

.lesson-content code {
    background: var(--bg-tertiary);
    padding: 2px 6px;
    border-radius: 4px;
    font-family: var(--font-code);
    color: var(--accent-pink);
    font-size: 0.85rem;
}

.lesson-content pre {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 15px;
    font-family: var(--font-code);
    font-size: 0.8rem;
    color: #34d399;
    overflow-x: auto;
    margin-bottom: 20px;
}

/* FLOATING ZALO CONTACT WIDGET */
.zalo-widget {
    position: fixed;
    bottom: 30px;
    right: 30px;
    background: linear-gradient(135deg, #0068ff, #06b6d4);
    color: white;
    padding: 12px 24px;
    border-radius: 50px;
    box-shadow: 0 8px 25px rgba(0, 104, 255, 0.4);
    z-index: 990;
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 700;
    font-size: 0.9rem;
    border: 1px solid rgba(255, 255, 255, 0.15);
    transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    font-family: var(--font-display);
}

.zalo-widget:hover {
    transform: scale(1.08) translateY(-4px);
    box-shadow: 0 15px 30px rgba(0, 104, 255, 0.6), 0 0 15px rgba(6, 182, 212, 0.4);
}

.zalo-widget i {
    font-size: 1.3rem;
    animation: pulseIcon 1.5s infinite;
}

@keyframes pulseIcon {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.2); }
}

/* Sound Toggle control button */
.sound-toggle-btn {
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--border-color);
    color: var(--text-muted);
    width: 38px;
    height: 38px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s;
}

.sound-toggle-btn:hover {
    background: rgba(139, 92, 246, 0.1);
    color: var(--accent-purple);
    border-color: var(--accent-purple);
    box-shadow: var(--neon-purple-glow);
}

.sound-toggle-btn.active {
    color: var(--accent-cyan);
    border-color: var(--accent-cyan);
    box-shadow: var(--neon-cyan-glow);
}

/* Footer */
footer {
    border-top: 1px solid var(--border-color);
    background: #040508;
    padding: 50px 0 30px;
    margin-top: 80px;
    text-align: center;
    font-size: 0.85rem;
    color: var(--text-muted);
}

.dev-by-text {
    font-weight: 700;
    color: var(--accent-pink);
    text-shadow: var(--neon-pink-glow);
    font-family: var(--font-display);
}

.confetti-active {
    animation: bounceResult 0.5s ease infinite alternate;
}

@keyframes bounceResult {
    0% { transform: scale(1); }
    100% { transform: scale(1.03); }
}

/* Responsive */
@media (max-width: 1024px) {
    .playground-layout {
        grid-template-columns: 1fr;
        height: auto;
    }
    .editor-pane {
        height: 350px;
    }
    .preview-pane {
        height: 350px;
    }
    .generator-layout {
        grid-template-columns: 1fr;
    }
    /* Disable custom cursor on mobile/tablets */
    html, body, button, a, input, select, textarea {
        cursor: auto !important;
    }
    .custom-cursor-dot, .custom-cursor-glow {
        display: none !important;
    }
}

@media (max-width: 768px) {
    .hero-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }
    .hero-tag {
        justify-content: center;
        margin: 0 auto 20px;
    }
    .hero-buttons {
        justify-content: center;
    }
    .hero-title {
        font-size: 2.5rem;
    }
    header {
        height: auto;
        padding: 15px 0;
    }
    .header-container {
        flex-direction: column;
        gap: 15px;
    }
    nav {
        flex-wrap: wrap;
        justify-content: center;
    }
    .zalo-widget {
        bottom: 20px;
        right: 20px;
        padding: 10px 18px;
        font-size: 0.8rem;
    }
}