@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+SC:wght@300;400;500;700;900&display=swap');

:root {
    --bg-primary: #f8f9fc;
    --bg-secondary: #eef0f7;
    --bg-card: #ffffff;
    --bg-card-hover: #f5f6fa;
    --text-primary: #1a1a2e;
    --text-secondary: #4a4a6a;
    --text-muted: #7a7a9a;
    --accent: #7c3aed;
    --accent-light: #8b5cf6;
    --accent-dark: #5b21b6;
    --accent-glow: rgba(124, 58, 237, 0.15);
    --gradient-1: linear-gradient(135deg, #7c3aed, #6366f1, #3b82f6);
    --gradient-2: linear-gradient(135deg, #8b5cf6, #818cf8);
    --gradient-3: linear-gradient(135deg, #5b21b6, #4f46e5);
    --border: rgba(124, 58, 237, 0.12);
    --border-hover: rgba(124, 58, 237, 0.3);
    --shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.12);
    --shadow-glow: 0 0 30px rgba(124, 58, 237, 0.1);
    --radius: 16px;
    --radius-sm: 10px;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="dark"] {
    --bg-primary: #0a0a1a;
    --bg-secondary: #111128;
    --bg-card: #161636;
    --bg-card-hover: #1c1c45;
    --text-primary: #f0f0ff;
    --text-secondary: #a0a0c8;
    --text-muted: #6a6a90;
    --accent: #8b5cf6;
    --accent-light: #a78bfa;
    --accent-dark: #6d28d9;
    --accent-glow: rgba(139, 92, 246, 0.3);
    --gradient-1: linear-gradient(135deg, #8b5cf6, #6366f1, #3b82f6);
    --gradient-2: linear-gradient(135deg, #a78bfa, #818cf8);
    --gradient-3: linear-gradient(135deg, #6d28d9, #4f46e5);
    --border: rgba(139, 92, 246, 0.15);
    --border-hover: rgba(139, 92, 246, 0.35);
    --shadow: 0 4px 24px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.4);
    --shadow-glow: 0 0 30px rgba(139, 92, 246, 0.15);
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.7;
    overflow-x: hidden;
}

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

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 16px 0;
    transition: var(--transition);
    background: transparent;
}

.navbar.scrolled {
    background: rgba(248, 249, 252, 0.9);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    padding: 10px 0;
}

[data-theme="dark"] .navbar.scrolled {
    background: rgba(10, 10, 26, 0.85);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--text-primary);
}

.logo-icon {
    font-size: 28px;
}

.logo-text {
    font-size: 22px;
    font-weight: 700;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 32px;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-size: 15px;
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-1);
    border-radius: 1px;
    transition: var(--transition);
}

.nav-links a:hover {
    color: var(--text-primary);
}

.nav-links a:hover::after {
    width: 100%;
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 12px;
}

.github-link {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: 1px solid var(--border);
    background: var(--bg-card);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
    color: var(--text-secondary);
    text-decoration: none;
}

.github-link:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    color: var(--text-primary);
    transform: scale(1.05);
}

.theme-toggle {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: 1px solid var(--border);
    background: var(--bg-card);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
    color: var(--text-secondary);
    position: relative;
    overflow: hidden;
}

.theme-toggle:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    color: var(--accent-light);
    transform: scale(1.05);
}

.theme-toggle .sun-icon,
.theme-toggle .moon-icon {
    position: absolute;
    transition: var(--transition);
}

.theme-toggle .sun-icon {
    opacity: 1;
    transform: rotate(0deg) scale(1);
}

.theme-toggle .moon-icon {
    opacity: 0;
    transform: rotate(90deg) scale(0.5);
}

[data-theme="dark"] .theme-toggle .sun-icon {
    opacity: 0;
    transform: rotate(-90deg) scale(0.5);
}

[data-theme="dark"] .theme-toggle .moon-icon {
    opacity: 1;
    transform: rotate(0deg) scale(1);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-secondary);
    border-radius: 2px;
    transition: var(--transition);
}

.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    position: relative;
    padding: 120px 24px 60px;
    overflow: hidden;
    background: radial-gradient(ellipse at 50% 30%, rgba(124, 58, 237, 0.08) 0%, transparent 60%),
                radial-gradient(ellipse at 20% 80%, rgba(99, 102, 241, 0.05) 0%, transparent 50%),
                var(--bg-primary);
}

[data-theme="dark"] .hero {
    background: radial-gradient(ellipse at 50% 30%, rgba(139, 92, 246, 0.12) 0%, transparent 60%),
                radial-gradient(ellipse at 20% 80%, rgba(99, 102, 241, 0.08) 0%, transparent 50%),
                var(--bg-primary);
}

.hero-bg-effects {
    position: absolute;
    inset: 0;
    pointer-events: none;
    overflow: hidden;
}

.floating-note {
    position: absolute;
    font-size: 32px;
    opacity: 0.08;
    color: var(--accent);
    animation: floatNote 20s infinite ease-in-out;
}

.note-1 { top: 15%; left: 10%; animation-delay: 0s; font-size: 40px; }
.note-2 { top: 25%; right: 15%; animation-delay: -4s; font-size: 36px; }
.note-3 { bottom: 30%; left: 20%; animation-delay: -8s; font-size: 44px; }
.note-4 { bottom: 20%; right: 10%; animation-delay: -12s; font-size: 28px; }
.note-5 { top: 60%; left: 50%; animation-delay: -16s; font-size: 32px; }

@keyframes floatNote {
    0%, 100% { transform: translateY(0) rotate(0deg); }
    25% { transform: translateY(-30px) rotate(10deg); }
    50% { transform: translateY(-15px) rotate(-5deg); }
    75% { transform: translateY(-40px) rotate(8deg); }
}

.hero-content {
    text-align: center;
    position: relative;
    z-index: 1;
}

.hero-visualizer {
    margin-bottom: 40px;
    position: relative;
    width: 240px;
    height: 240px;
    margin-left: auto;
    margin-right: auto;
}

.disc-container {
    position: relative;
    width: 100%;
    height: 100%;
}

.disc {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 140px;
    height: 140px;
    border-radius: 50%;
    background: linear-gradient(135deg, #e8e8f5, #d4d4f0);
    box-shadow: 0 0 40px rgba(124, 58, 237, 0.15),
                inset 0 0 30px rgba(255, 255, 255, 0.5);
    animation: discSpin 8s linear infinite;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 3px solid rgba(124, 58, 237, 0.2);
}

[data-theme="dark"] .disc {
    background: linear-gradient(135deg, #1a1a3e, #2a2a5e);
    box-shadow: 0 0 40px rgba(139, 92, 246, 0.2),
                inset 0 0 30px rgba(0, 0, 0, 0.3);
    border: 3px solid rgba(139, 92, 246, 0.3);
}

.disc-inner {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--accent), var(--accent-dark));
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 0 20px var(--accent-glow);
}

.disc-label {
    font-size: 22px;
}

@keyframes discSpin {
    from { transform: translate(-50%, -50%) rotate(0deg); }
    to { transform: translate(-50%, -50%) rotate(360deg); }
}

.spectrum-ring {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 240px;
    height: 240px;
}

.spectrum-ring .bar {
    position: absolute;
    bottom: 50%;
    left: 50%;
    width: 3px;
    background: var(--gradient-1);
    border-radius: 2px;
    transform-origin: bottom center;
    opacity: 0.8;
    animation: spectrumPulse 1.2s ease-in-out infinite alternate;
}

@keyframes spectrumPulse {
    0% { height: 12px; opacity: 0.4; }
    100% { height: 35px; opacity: 0.9; }
}

.hero-title {
    margin-bottom: 16px;
}

.title-gradient {
    font-size: clamp(48px, 8vw, 80px);
    font-weight: 900;
    background: linear-gradient(135deg, #a78bfa, #8b5cf6, #6366f1, #818cf8);
    background-size: 300% 300%;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: gradientShift 6s ease infinite;
    letter-spacing: -2px;
}

@keyframes gradientShift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

.hero-subtitle {
    font-size: clamp(18px, 3vw, 24px);
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 12px;
}

.hero-desc {
    font-size: 15px;
    color: var(--text-muted);
    margin-bottom: 36px;
    line-height: 1.8;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 48px;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    border-radius: 50px;
    font-size: 16px;
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition);
    cursor: pointer;
    border: none;
    font-family: inherit;
}

.btn-primary {
    background: var(--gradient-1);
    color: #fff;
    box-shadow: 0 4px 20px rgba(139, 92, 246, 0.35);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(139, 92, 246, 0.5);
}

.btn-secondary {
    background: rgba(139, 92, 246, 0.1);
    color: var(--accent-light);
    border: 1px solid var(--border);
}

.btn-secondary:hover {
    background: rgba(139, 92, 246, 0.2);
    border-color: var(--border-hover);
    transform: translateY(-2px);
}

.hero-stats {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 32px;
    flex-wrap: wrap;
}

.stat-item {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 32px;
    font-weight: 900;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    font-size: 13px;
    color: var(--text-muted);
    font-weight: 500;
}

.stat-divider {
    width: 1px;
    height: 40px;
    background: var(--border);
}

.scroll-indicator {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    animation: scrollBounce 2s infinite;
}

.mouse {
    width: 26px;
    height: 40px;
    border: 2px solid var(--text-muted);
    border-radius: 13px;
    display: flex;
    justify-content: center;
    padding-top: 8px;
    opacity: 0.4;
}

.wheel {
    width: 3px;
    height: 8px;
    background: var(--text-muted);
    border-radius: 2px;
    animation: wheelScroll 2s infinite;
}

@keyframes scrollBounce {
    0%, 100% { transform: translateX(-50%) translateY(0); }
    50% { transform: translateX(-50%) translateY(10px); }
}

@keyframes wheelScroll {
    0% { opacity: 1; transform: translateY(0); }
    100% { opacity: 0; transform: translateY(10px); }
}

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

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-tag {
    display: inline-block;
    padding: 6px 18px;
    background: rgba(139, 92, 246, 0.1);
    border: 1px solid var(--border);
    border-radius: 50px;
    font-size: 13px;
    font-weight: 600;
    color: var(--accent-light);
    margin-bottom: 16px;
    letter-spacing: 1px;
}

.section-title {
    font-size: clamp(28px, 4vw, 40px);
    font-weight: 800;
    margin-bottom: 12px;
    background: linear-gradient(135deg, var(--text-primary), var(--text-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-desc {
    font-size: 16px;
    color: var(--text-muted);
    max-width: 500px;
    margin: 0 auto;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 32px 28px;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--gradient-1);
    opacity: 0;
    transition: var(--transition);
}

.feature-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

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

.feature-icon {
    width: 56px;
    height: 56px;
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    background: rgba(139, 92, 246, 0.1);
    color: var(--accent, #8b5cf6);
    transition: var(--transition);
}

.feature-card:hover .feature-icon {
    background: rgba(139, 92, 246, 0.2);
    transform: scale(1.05);
}

.feature-card h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--text-primary);
}

.feature-card p {
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.7;
}

.discover {
    background: var(--bg-secondary);
}

.discover-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 20px;
}

.discover-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px 20px;
    text-align: center;
    transition: var(--transition);
}

.discover-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.discover-icon {
    font-size: 36px;
    margin-bottom: 14px;
}

.discover-card h3 {
    font-size: 16px;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text-primary);
}

.discover-card p {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.6;
}

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

.playlist-visual {
    display: flex;
    justify-content: center;
}

.playlist-stack {
    position: relative;
    width: 280px;
    height: 320px;
}

.playlist-cover {
    position: absolute;
    width: 200px;
    height: 200px;
    border-radius: 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-size: 40px;
    box-shadow: var(--shadow-lg);
    transition: var(--transition);
    cursor: pointer;
    border: 1px solid var(--border);
}

.playlist-cover span {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
}

.playlist-cover:nth-child(1) {
    background: linear-gradient(135deg, hsl(var(--hue, 270), 60%, 20%), hsl(var(--hue, 270), 60%, 30%));
    top: 0;
    left: 0;
    z-index: 3;
}

.playlist-cover:nth-child(2) {
    background: linear-gradient(135deg, hsl(var(--hue, 200), 60%, 20%), hsl(var(--hue, 200), 60%, 30%));
    top: 60px;
    left: 40px;
    z-index: 2;
}

.playlist-cover:nth-child(3) {
    background: linear-gradient(135deg, hsl(var(--hue, 340), 60%, 20%), hsl(var(--hue, 340), 60%, 30%));
    top: 120px;
    left: 80px;
    z-index: 1;
}

.playlist-cover:hover {
    transform: scale(1.05) rotate(-2deg);
    z-index: 10;
}

.playlist-features {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.playlist-feature-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    padding: 20px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    transition: var(--transition);
}

.playlist-feature-item:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateX(4px);
}

.pf-icon {
    font-size: 24px;
    flex-shrink: 0;
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(139, 92, 246, 0.1);
    border-radius: 12px;
}

.pf-content h4 {
    font-size: 16px;
    font-weight: 700;
    margin-bottom: 4px;
    color: var(--text-primary);
}

.pf-content p {
    font-size: 13px;
    color: var(--text-muted);
}

.highlights-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.highlight-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px 24px;
    text-align: center;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.highlight-card::after {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 50% 0%, var(--accent-glow), transparent 70%);
    opacity: 0;
    transition: var(--transition);
}

.highlight-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-4px);
}

.highlight-card:hover::after {
    opacity: 1;
}

.highlight-emoji {
    font-size: 40px;
    margin-bottom: 16px;
    position: relative;
    z-index: 1;
}

.highlight-card h3 {
    font-size: 16px;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text-primary);
    position: relative;
    z-index: 1;
}

.highlight-card p {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.6;
    position: relative;
    z-index: 1;
}

.tech {
    background: var(--bg-secondary);
}

.tech-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.tech-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px 24px;
    text-align: center;
    transition: var(--transition);
}

.tech-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-4px);
}

.tech-badge {
    display: inline-block;
    padding: 4px 14px;
    background: rgba(139, 92, 246, 0.15);
    border-radius: 50px;
    font-size: 12px;
    font-weight: 700;
    color: var(--accent-light);
    margin-bottom: 14px;
    letter-spacing: 1px;
}

.tech-card h3 {
    font-size: 17px;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text-primary);
}

.tech-card p {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.6;
}

.download {
    padding: 120px 0;
}

.download-wrapper {
    position: relative;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 80px 40px;
    text-align: center;
    overflow: hidden;
}

.download-bg-visualizer {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 120px;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    gap: 4px;
    padding: 0 20px;
    opacity: 0.15;
    pointer-events: none;
}

.download-bar {
    flex: 1;
    max-width: 30px;
    background: var(--gradient-1);
    border-radius: 4px 4px 0 0;
    animation: downloadPulse 1.5s ease-in-out infinite alternate;
    animation-delay: calc(var(--i) * 0.1s);
}

@keyframes downloadPulse {
    0% { height: 20%; }
    100% { height: 80%; }
}

.download-content {
    position: relative;
    z-index: 1;
}

.download-icon {
    font-size: 64px;
    margin-bottom: 20px;
}

.download-wrapper h2 {
    font-size: clamp(28px, 4vw, 40px);
    font-weight: 800;
    margin-bottom: 8px;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.download-wrapper > .download-content > p {
    font-size: 16px;
    color: var(--text-muted);
    margin-bottom: 32px;
}

.download-info {
    display: flex;
    justify-content: center;
    gap: 40px;
    margin-bottom: 36px;
    flex-wrap: wrap;
}

.info-item {
    text-align: center;
}

.info-label {
    display: block;
    font-size: 12px;
    color: var(--text-muted);
    margin-bottom: 4px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

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

.info-value.free {
    color: #10b981;
}

.btn-download {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 18px 48px;
    background: var(--gradient-1);
    color: #fff;
    border-radius: 50px;
    font-size: 18px;
    font-weight: 700;
    text-decoration: none;
    transition: var(--transition);
    box-shadow: 0 4px 24px rgba(139, 92, 246, 0.4);
}

.btn-download:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 36px rgba(139, 92, 246, 0.55);
}

.download-tip {
    font-size: 13px;
    color: var(--text-muted);
    margin-top: 20px;
}

.social-cards {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    max-width: 800px;
    margin: 0 auto;
}

.social-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 36px 28px;
    text-align: center;
    transition: var(--transition);
    text-decoration: none;
    color: inherit;
    display: block;
}

.social-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.qq-card {
    cursor: pointer;
}

.social-icon {
    font-size: 32px;
    margin-bottom: 16px;
    color: var(--accent);
}

.qq-card .social-icon {
    color: #12b7f5;
}

.social-card h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text-primary);
}

.qq-number {
    font-size: 28px;
    font-weight: 900;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 16px;
}

.social-btn {
    display: inline-block;
    padding: 8px 24px;
    background: rgba(139, 92, 246, 0.15);
    border-radius: 50px;
    font-size: 14px;
    font-weight: 600;
    color: var(--accent-light);
    transition: var(--transition);
}

.social-card:hover .social-btn {
    background: rgba(139, 92, 246, 0.25);
}

.feedback-card p {
    font-size: 14px;
    color: var(--text-muted);
    margin-bottom: 4px;
}

.feedback-desc {
    font-size: 13px !important;
    color: var(--text-muted) !important;
    line-height: 1.6;
}

.footer {
    padding: 60px 0 30px;
    border-top: 1px solid var(--border);
    background: var(--bg-secondary);
}

.footer-content {
    text-align: center;
}

.footer-brand {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    margin-bottom: 12px;
}

.footer-brand .logo-text {
    font-size: 20px;
}

.footer-desc {
    font-size: 14px;
    color: var(--text-muted);
    margin-bottom: 24px;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 24px;
    margin-bottom: 30px;
    flex-wrap: wrap;
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
    transition: var(--transition);
}

.footer-links a:hover {
    color: var(--accent-light);
}

.footer-bottom p {
    font-size: 13px;
    color: var(--text-muted);
}

.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 44px;
    height: 44px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--accent-light);
    cursor: pointer;
    transition: var(--transition);
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    z-index: 999;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-2px);
}

@media (max-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .highlights-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .tech-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .discover-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: rgba(248, 249, 252, 0.95);
        backdrop-filter: blur(20px);
        -webkit-backdrop-filter: blur(20px);
        flex-direction: column;
        padding: 20px;
        gap: 16px;
        border-bottom: 1px solid var(--border);
    }
    [data-theme="dark"] .nav-links {
        background: rgba(10, 10, 26, 0.95);
    }
    .nav-links.active {
        display: flex;
    }
    .nav-toggle {
        display: flex;
    }
    .nav-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }
    .nav-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    .nav-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -5px);
    }
    .hero {
        padding: 100px 20px 40px;
    }
    .hero-visualizer {
        width: 180px;
        height: 180px;
    }
    .disc {
        width: 100px;
        height: 100px;
    }
    .disc-inner {
        width: 36px;
        height: 36px;
    }
    .spectrum-ring {
        width: 180px;
        height: 180px;
    }
    .hero-stats {
        gap: 20px;
    }
    .stat-number {
        font-size: 24px;
    }
    .features-grid {
        grid-template-columns: 1fr;
    }
    .discover-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .playlist-showcase {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    .playlist-visual {
        order: -1;
    }
    .playlist-stack {
        width: 220px;
        height: 260px;
    }
    .playlist-cover {
        width: 160px;
        height: 160px;
        font-size: 30px;
    }
    .highlights-grid {
        grid-template-columns: 1fr;
    }
    .tech-grid {
        grid-template-columns: 1fr;
    }
    .social-cards {
        grid-template-columns: 1fr;
    }
    .download-wrapper {
        padding: 60px 24px;
    }
    .btn-download {
        padding: 16px 36px;
        font-size: 16px;
    }
    .section {
        padding: 70px 0;
    }
}

@media (max-width: 480px) {
    .discover-grid {
        grid-template-columns: 1fr;
    }
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    .btn {
        width: 100%;
        max-width: 280px;
        justify-content: center;
    }
    .download-info {
        gap: 20px;
    }
}

.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}