/* ============================================================
   Metronome - 官方网站样式表
   设计语言：暗色主题 / 玻璃拟态 / 蓝橙配色
   ============================================================ */

/* === CSS Custom Properties === */
:root {
    /* 主色板 */
    --bg-primary: #0A0A0F;
    --bg-secondary: #0F0F16;
    --bg-card: #14141E;
    --bg-card-hover: #1A1A28;
    --bg-elevated: rgba(20, 20, 40, 0.8);

    /* 强调色 */
    --primary: #2B8FFF;
    --primary-light: #55AAFF;
    --primary-subtle: rgba(43, 143, 255, 0.12);
    --primary-glow: rgba(43, 143, 255, 0.3);
    --accent: #FF9F0A;
    --accent-light: #FFB340;
    --accent-subtle: rgba(255, 159, 10, 0.12);
    --accent-glow: rgba(255, 159, 10, 0.25);

    /* 文本 */
    --text-primary: #F0F0F5;
    --text-secondary: #9898B0;
    --text-body: rgba(240, 240, 245, 0.82);
    --text-muted: rgba(240, 240, 245, 0.45);

    /* 边框与表面 */
    --border-subtle: rgba(255, 255, 255, 0.06);
    --border-card: #252538;
    --border-hover: #3A3A55;

    /* 玻璃拟态 */
    --glass-bg: rgba(20, 20, 40, 0.6);
    --glass-border: rgba(255, 255, 255, 0.08);
    --glass-blur: 20px;

    /* 辉光 */
    --glow-blue: rgba(43, 143, 255, 0.15);
    --glow-orange: rgba(255, 159, 10, 0.1);

    /* 布局 */
    --container: 1200px;
    --nav-height: 64px;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --radius-full: 9999px;

    /* 动画 */
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
    --transition-fast: 0.2s var(--ease-out);
    --transition-base: 0.35s var(--ease-out);
    --transition-slow: 0.5s var(--ease-out);
}

/* === Reset & Base === */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-primary);
    color: var(--text-body);
    line-height: 1.6;
    overflow-x: hidden;
}

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

img {
    max-width: 100%;
    height: auto;
    display: block;
}

button {
    cursor: pointer;
    border: none;
    background: none;
    font-family: inherit;
    font-size: inherit;
    color: inherit;
}

.container {
    max-width: var(--container);
    margin: 0 auto;
    padding: 0 20px;
}

/* === Typography === */
h1, h2, h3, h4, h5, h6 {
    color: var(--text-primary);
    font-weight: 700;
    line-height: 1.2;
}

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

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

.section-header {
    text-align: center;
    margin-bottom: 60px;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.section-tagline {
    display: inline-block;
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--primary-light);
    margin-bottom: 16px;
}

.section-title {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 800;
    margin-bottom: 16px;
    background: linear-gradient(135deg, var(--text-primary), var(--primary-light));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-desc {
    font-size: 1.1rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ============================================================
   Navigation
   ============================================================ */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    height: var(--nav-height);
    background: rgba(10, 10, 15, 0.6);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-subtle);
    transition: background var(--transition-base);
}

.nav.scrolled {
    background: rgba(10, 10, 15, 0.92);
}

.nav-container {
    max-width: var(--container);
    margin: 0 auto;
    padding: 0 20px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-primary);
    font-weight: 700;
    font-size: 1.15rem;
}

.nav-logo-icon {
    border-radius: 6px;
    flex-shrink: 0;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 4px;
}

.nav-link {
    padding: 8px 16px;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: color var(--transition-fast);
    position: relative;
    border-radius: var(--radius-sm);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 2px;
    left: 16px;
    right: 16px;
    height: 2px;
    background: var(--primary);
    border-radius: 2px;
    transform: scaleX(0);
    transition: transform var(--transition-base);
}

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

.nav-link:hover::after {
    transform: scaleX(1);
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 8px;
}

/* === Buttons === */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-weight: 600;
    font-size: 0.9rem;
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
    white-space: nowrap;
}

.btn-sm {
    padding: 8px 20px;
    font-size: 0.85rem;
}

.btn-lg {
    padding: 14px 32px;
    font-size: 1rem;
}

.btn-block {
    width: 100%;
    padding: 12px 24px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), #1A7BE5);
    color: white;
    box-shadow: 0 4px 20px var(--primary-glow);
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 6px 28px var(--primary-glow);
}

.btn-ghost {
    background: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border-card);
}

.btn-ghost:hover {
    border-color: var(--border-hover);
    background: rgba(255, 255, 255, 0.04);
}

.lang-toggle {
    font-size: 0.8rem;
    padding: 6px 14px;
    color: var(--text-secondary);
    border-color: var(--border-subtle);
}

.lang-toggle:hover {
    color: var(--text-primary);
    border-color: var(--border-card);
}

/* Hamburger */
.nav-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 36px;
    height: 36px;
    padding: 6px;
    border-radius: var(--radius-sm);
}

.nav-toggle span {
    display: block;
    width: 100%;
    height: 2px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: all var(--transition-fast);
    transform-origin: center;
}

.nav-toggle.active span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}

.nav-toggle.active span:nth-child(2) {
    opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

/* ============================================================
   Hero
   ============================================================ */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    padding-top: var(--nav-height);
}

.hero-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
}

.hero-gradient {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(600px circle at 20% 40%, var(--glow-blue), transparent 60%),
        radial-gradient(500px circle at 80% 60%, var(--glow-orange), transparent 60%),
        radial-gradient(800px circle at 50% 80%, rgba(43, 143, 255, 0.05), transparent 60%),
        linear-gradient(180deg, var(--bg-primary) 0%, transparent 20%, transparent 80%, var(--bg-primary) 100%);
    animation: heroPulse 8s ease-in-out infinite alternate;
}

@keyframes heroPulse {
    0% { opacity: 0.7; }
    100% { opacity: 1; }
}

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

.particle {
    position: absolute;
    width: 2px;
    height: 2px;
    background: var(--primary);
    border-radius: 50%;
    opacity: 0;
    animation: particleFloat 6s ease-in-out infinite;
    pointer-events: none;
}

@keyframes particleFloat {
    0% {
        opacity: 0;
        transform: translateY(0) scale(0);
    }
    20% {
        opacity: 0.6;
    }
    80% {
        opacity: 0.6;
    }
    100% {
        opacity: 0;
        transform: translateY(-400px) scale(1);
    }
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 800px;
    padding: 0 20px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 16px;
    background: var(--primary-subtle);
    border: 1px solid rgba(43, 143, 255, 0.2);
    border-radius: var(--radius-full);
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--primary-light);
    margin-bottom: 32px;
}

.badge-dot {
    width: 8px;
    height: 8px;
    background: var(--primary);
    border-radius: 50%;
    animation: dotPulse 2s ease-in-out infinite;
}

@keyframes dotPulse {
    0%, 100% { transform: scale(0.8); opacity: 0.6; }
    50% { transform: scale(1.2); opacity: 1; }
}

.hero-title-block {
    margin-bottom: 24px;
}

.hero-title {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.hero-title-line {
    font-size: clamp(2.5rem, 7vw, 5rem);
    font-weight: 900;
    letter-spacing: -0.02em;
    line-height: 1.1;
    background: linear-gradient(135deg, var(--text-primary) 0%, #B0B0D0 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-title-accent {
    background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: clamp(1rem, 1.8vw, 1.2rem);
    color: var(--text-secondary);
    margin-bottom: 36px;
    line-height: 1.7;
}

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

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

.hero-stat {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
}

.hero-stat-value {
    font-size: 1.6rem;
    font-weight: 800;
    color: var(--text-primary);
}

.hero-stat-label {
    font-size: 0.8rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

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

/* ============================================================
   Hero 3D Phone 背景动画 -- 环形滚动
   ============================================================ */
.hero-phone-3d {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 460px;
    height: 460px;
    margin: -230px 0 0 -230px;
    perspective: 1600px;
    pointer-events: none;
    z-index: 0;
    opacity: 0.32;
    filter: blur(2px);
    animation: phoneBob 14s ease-in-out infinite;
}

/* 整体上下浮动，制造呼吸感 */
@keyframes phoneBob {
    0%, 100% { transform: translateY(-12px); }
    50%      { transform: translateY(12px); }
}

.phone-ring {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    transform-style: preserve-3d;
    animation: ringSpin 16s infinite cubic-bezier(0.42, 0, 0.58, 1);
    will-change: transform;
}

/* 环形滚动节奏：8 张真实截图，每张正面停留 1.6s + 滚动 0.4s */
@keyframes ringSpin {
    0%      { transform: rotateY(0deg); }
    10%     { transform: rotateY(0deg); }
    12.5%   { transform: rotateY(45deg); }
    22.5%   { transform: rotateY(45deg); }
    25%     { transform: rotateY(90deg); }
    35%     { transform: rotateY(90deg); }
    37.5%   { transform: rotateY(135deg); }
    47.5%   { transform: rotateY(135deg); }
    50%     { transform: rotateY(180deg); }
    60%     { transform: rotateY(180deg); }
    62.5%   { transform: rotateY(225deg); }
    72.5%   { transform: rotateY(225deg); }
    75%     { transform: rotateY(270deg); }
    85%     { transform: rotateY(270deg); }
    87.5%   { transform: rotateY(315deg); }
    97.5%   { transform: rotateY(315deg); }
    100%    { transform: rotateY(360deg); }
}

.phone-card {
    --R: 280px;
    position: absolute;
    top: 50%;
    left: 50%;
    width: 170px;
    height: 360px;
    margin: -180px 0 0 -85px;
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
    transform-style: preserve-3d;
}

/* 8 张真实截图均匀贴在圆柱外壁，随环旋转依次滚到正面 */
.card-0 { transform: rotateY(0deg)   translateZ(var(--R)); }
.card-1 { transform: rotateY(45deg)  translateZ(var(--R)); }
.card-2 { transform: rotateY(90deg)  translateZ(var(--R)); }
.card-3 { transform: rotateY(135deg) translateZ(var(--R)); }
.card-4 { transform: rotateY(180deg) translateZ(var(--R)); }
.card-5 { transform: rotateY(225deg) translateZ(var(--R)); }
.card-6 { transform: rotateY(270deg) translateZ(var(--R)); }
.card-7 { transform: rotateY(315deg) translateZ(var(--R)); }

.phone-card-frame {
    position: absolute;
    inset: 0;
    border-radius: 32px;
    background: linear-gradient(145deg, #202028 0%, #0a0a0e 50%, #1a1a22 100%);
    border: 2px solid rgba(255, 255, 255, 0.08);
    box-shadow: inset 0 0 0 2px rgba(0, 0, 0, 0.5), 0 20px 50px rgba(0, 0, 0, 0.5);
    overflow: hidden;
}

.phone-card-notch {
    position: absolute;
    top: 10px;
    left: 50%;
    width: 70px;
    height: 20px;
    margin-left: -35px;
    background: #000;
    border-radius: 12px;
    z-index: 10;
}

.phone-card-frame img {
    position: absolute;
    top: 6px;
    left: 6px;
    right: 6px;
    bottom: 6px;
    object-fit: cover;
    border-radius: 26px;
    display: block;
}

/* 响应式：小屏缩小并弱化，避免遮挡文字 */
@media (max-width: 900px) {
    .hero-phone-3d { width: 380px; height: 380px; margin: -190px 0 0 -190px; opacity: 0.24; }
    .phone-card { width: 140px; height: 300px; margin: -150px 0 0 -70px; --R: 225px; }
}
@media (max-width: 600px) {
    .hero-phone-3d { width: 300px; height: 300px; margin: -150px 0 0 -150px; opacity: 0.18; filter: blur(3px); }
    .phone-card { width: 116px; height: 248px; margin: -124px 0 0 -58px; --R: 185px; }
}

/* 尊重减少动效偏好：静态展示首页截图 */
@media (prefers-reduced-motion: reduce) {
    .hero-phone-3d, .phone-ring { animation: none !important; }
    .phone-card:not(.card-0) { display: none; }
}

/* ============================================================
   Features
   ============================================================ */
.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.feature-card {
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    border-radius: var(--radius-lg);
    padding: 28px 24px;
    transition: all var(--transition-base);
    position: relative;
    border-top: 3px solid transparent;
}

.feature-card:nth-child(1) { border-top-color: var(--primary); }
.feature-card:nth-child(2) { border-top-color: var(--accent); }
.feature-card:nth-child(3) { border-top-color: #55C2FF; }
.feature-card:nth-child(4) { border-top-color: #28C3AE; }
.feature-card:nth-child(5) { border-top-color: #F0BC32; }
.feature-card:nth-child(6) { border-top-color: #E85D8F; }
.feature-card:nth-child(7) { border-top-color: #ED6393; }
.feature-card:nth-child(8) { border-top-color: #00FFFF; }

.feature-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-4px);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.feature-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    background: var(--primary-subtle);
    border-radius: var(--radius-md);
    margin-bottom: 16px;
    color: var(--primary-light);
    transition: all var(--transition-base);
}

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

.feature-title {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.feature-desc {
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.65;
}

/* ============================================================
   App Preview / Showcase
   ============================================================ */
.showcase {
    display: flex;
    align-items: center;
    gap: 80px;
    margin-bottom: 100px;
}

.showcase:last-child {
    margin-bottom: 0;
}

.showcase-reverse {
    flex-direction: row-reverse;
}

/* --- iPhone Mockup --- */
.showcase-frame {
    flex: 0 0 auto;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

/* Glow behind phone */
.showcase-frame::before {
    content: '';
    position: absolute;
    width: 380px;
    height: 380px;
    border-radius: 50%;
    background: radial-gradient(circle, var(--glow-blue) 0%, transparent 70%);
    opacity: 0.8;
    pointer-events: none;
}

.showcase-reverse .showcase-frame::before {
    background: radial-gradient(circle, var(--glow-orange) 0%, transparent 70%);
}

.ios-mockup {
    position: relative;
    width: 280px;
    padding: 10px;
    background: linear-gradient(145deg, #1a1a1a, #0d0d0d);
    border-radius: 44px;
    box-shadow:
        0 0 0 1px rgba(255,255,255,0.08),
        0 30px 80px rgba(0,0,0,0.55),
        0 10px 30px rgba(0,0,0,0.3);
    z-index: 1;
}

/* Side buttons */
.ios-mockup::before {
    content: '';
    position: absolute;
    right: -3px;
    top: 100px;
    width: 3px;
    height: 50px;
    background: linear-gradient(180deg, #3a3a3a, #222);
    border-radius: 0 2px 2px 0;
}

.ios-mockup::after {
    content: '';
    position: absolute;
    left: -3px;
    top: 120px;
    width: 3px;
    height: 30px;
    background: linear-gradient(180deg, #3a3a3a, #222);
    border-radius: 2px 0 0 2px;
}

.ios-screen {
    position: relative;
    border-radius: 34px;
    overflow: hidden;
    background: #000;
    aspect-ratio: 9 / 19.5;
}

.ios-screen img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

/* Glass reflection overlay */
.ios-reflection {
    position: absolute;
    inset: 0;
    background: linear-gradient(
        165deg,
        rgba(255,255,255,0.07) 0%,
        rgba(255,255,255,0.03) 25%,
        transparent 50%,
        rgba(255,255,255,0.01) 75%,
        rgba(255,255,255,0.04) 100%
    );
    pointer-events: none;
    z-index: 5;
    border-radius: 34px;
}

/* Ambient glow under phone */
.phone-glow {
    position: absolute;
    bottom: -30px;
    left: 50%;
    transform: translateX(-50%);
    width: 180px;
    height: 40px;
    background: radial-gradient(ellipse at center, var(--primary-glow) 0%, transparent 70%);
    filter: blur(10px);
    opacity: 0.6;
    pointer-events: none;
    z-index: 0;
}

/* --- Feature Grid --- */
.showcase-features {
    flex: 1;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

.showcase-feature {
    display: flex;
    align-items: flex-start;
    gap: 14px;
    padding: 16px;
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    border-radius: var(--radius-md);
    transition: all var(--transition-base);
}

.showcase-feature:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-2px);
}

.showcase-feature-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    min-width: 40px;
    background: var(--primary-subtle);
    border-radius: var(--radius-sm);
    color: var(--primary);
}

.showcase-feature strong {
    display: block;
    font-size: 0.88rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.showcase-feature span {
    font-size: 0.8rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

/* ============================================================
   Themes Carousel
   ============================================================ */
.themes-carousel {
    position: relative;
    max-width: 100%;
    overflow: hidden;
}

.themes-track {
    display: flex;
    gap: 20px;
    overflow-x: auto;
    scroll-snap-type: x mandatory;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    padding: 8px 0 20px;
}

.themes-track::-webkit-scrollbar {
    display: none;
}

.theme-card {
    flex: 0 0 240px;
    scroll-snap-align: start;
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: all var(--transition-base);
    cursor: pointer;
}

.theme-card:hover {
    transform: translateY(-4px);
    border-color: var(--border-hover);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.3);
}

.theme-visual {
    height: 160px;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.dark-bg { background: linear-gradient(135deg, #121212, #1a1a2e); }
.light-bg { background: linear-gradient(135deg, #F8F5FF, #E8E5F5); }
.audio-bg { background: linear-gradient(135deg, #07080C, #1a1a2e); }
.concert-bg { background: linear-gradient(135deg, #2C1810, #4a2a1a); }
.studio-bg { background: linear-gradient(135deg, #1A1A1A, #0a2a0a); }
.stage-bg { background: linear-gradient(135deg, #1A0033, #3a0055); }
.classic-bg { background: linear-gradient(135deg, #F5F1E6, #E8E0C8); }
.chinese-bg { background: linear-gradient(135deg, #F7F5E9, #E8D8C8); }
.pro-bg { background: linear-gradient(135deg, #2A2A45, #1a1a3a); }

.theme-visual-beat {
    width: 6px;
    height: 60px;
    background: var(--theme-accent, var(--accent));
    border-radius: 3px;
    animation: themeBeat 1s ease-in-out infinite;
    transform-origin: center bottom;
}

.theme-card:nth-child(2) .theme-visual-beat { animation-delay: 0.1s; }
.theme-card:nth-child(3) .theme-visual-beat { animation-delay: 0.2s; }
.theme-card:nth-child(4) .theme-visual-beat { animation-delay: 0.3s; }
.theme-card:nth-child(5) .theme-visual-beat { animation-delay: 0.4s; }
.theme-card:nth-child(6) .theme-visual-beat { animation-delay: 0.5s; }
.theme-card:nth-child(7) .theme-visual-beat { animation-delay: 0.6s; }
.theme-card:nth-child(8) .theme-visual-beat { animation-delay: 0.7s; }
.theme-card:nth-child(9) .theme-visual-beat { animation-delay: 0.8s; }

@keyframes themeBeat {
    0%, 100% { transform: scaleY(0.3); opacity: 0.4; }
    50% { transform: scaleY(1); opacity: 1; }
}

.theme-info {
    padding: 16px;
}

.theme-info h4 {
    font-size: 0.95rem;
    font-weight: 700;
    margin-bottom: 4px;
}

.theme-info p {
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.themes-controls {
    display: flex;
    justify-content: center;
    gap: 12px;
    margin-top: 16px;
}

.theme-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.theme-btn:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    color: var(--text-primary);
}

/* ============================================================
   Feature Shots 功能实拍
   ============================================================ */
.shots-carousel {
    position: relative;
}

.shots-track {
    display: flex;
    gap: 20px;
    overflow-x: auto;
    scroll-snap-type: x mandatory;
    padding: 10px 4px 24px;
    scrollbar-width: none;
    -ms-overflow-style: none;
}
.shots-track::-webkit-scrollbar {
    display: none;
}

.shot-card {
    flex: 0 0 232px;
    scroll-snap-align: start;
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: transform var(--transition-base), border-color var(--transition-base);
}
.shot-card:hover {
    transform: translateY(-4px);
    border-color: var(--border-hover);
}

.shot-img {
    width: 100%;
    aspect-ratio: 1170 / 2532;
    background: #06070a;
    overflow: hidden;
}
.shot-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: transform var(--transition-base);
}
.shot-card:hover .shot-img img {
    transform: scale(1.03);
}

.shot-info {
    padding: 18px 20px 22px;
}
.shot-info h3 {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
}
.shot-info p {
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.shots-controls {
    display: flex;
    justify-content: center;
    gap: 12px;
    margin-top: 8px;
}

@media (max-width: 600px) {
    .shot-card { flex: 0 0 200px; }
}

/* ============================================================
   How It Works / Steps
   ============================================================ */
.steps-grid {
    display: flex;
    align-items: center;
    gap: 20px;
    justify-content: center;
}

.step-card {
    flex: 1;
    max-width: 320px;
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    border-radius: var(--radius-lg);
    padding: 36px 28px;
    text-align: center;
    position: relative;
    transition: all var(--transition-base);
}

.step-card:hover {
    transform: translateY(-4px);
    border-color: var(--border-hover);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.step-number {
    position: absolute;
    top: -14px;
    left: 50%;
    transform: translateX(-50%);
    width: 28px;
    height: 28px;
    background: var(--primary);
    color: white;
    font-size: 0.8rem;
    font-weight: 800;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 12px var(--primary-glow);
}

.step-icon {
    color: var(--primary-light);
    margin-bottom: 16px;
    display: flex;
    justify-content: center;
}

.step-title {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.step-desc {
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.65;
}

.step-arrow {
    flex-shrink: 0;
    color: var(--text-muted);
}

/* ============================================================
   Why Metronome
   ============================================================ */
.why-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.why-card {
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    border-radius: var(--radius-lg);
    padding: 32px 24px;
    text-align: center;
    transition: all var(--transition-base);
}

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

.why-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    background: var(--primary-subtle);
    border-radius: 50%;
    color: var(--primary-light);
    margin-bottom: 20px;
    transition: all var(--transition-base);
}

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

.why-card h3 {
    font-size: 1.05rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.why-card p {
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.65;
}

/* ============================================================
   Pricing
   ============================================================ */
.pricing-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    max-width: 1000px;
    margin: 0 auto;
}

.pricing-card {
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    border-radius: var(--radius-xl);
    padding: 36px 28px;
    display: flex;
    flex-direction: column;
    transition: all var(--transition-base);
    position: relative;
}

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

.pricing-card-featured {
    border-color: var(--primary);
    background: linear-gradient(180deg, rgba(43, 143, 255, 0.06), var(--bg-card));
    transform: scale(1.05);
}

.pricing-card-featured:hover {
    border-color: var(--primary-light);
}

.pricing-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    padding: 4px 16px;
    font-size: 0.75rem;
    font-weight: 700;
    background: var(--primary);
    color: white;
    border-radius: var(--radius-full);
    white-space: nowrap;
    box-shadow: 0 4px 12px var(--primary-glow);
}

.pricing-name {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 16px;
}

.pricing-price {
    margin-bottom: 24px;
}

.pricing-amount {
    font-size: 2.2rem;
    font-weight: 900;
    color: var(--text-primary);
}

.pricing-period {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-left: 4px;
}

.pricing-features {
    list-style: none;
    flex: 1;
    margin-bottom: 24px;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.pricing-feature {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.85rem;
}

.pricing-feature.included svg {
    color: var(--accent);
    flex-shrink: 0;
}

.pricing-feature.excluded svg {
    color: var(--text-muted);
    opacity: 0.4;
}

.pricing-feature.excluded {
    color: var(--text-muted);
}

.pricing-note {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-align: center;
    margin-top: 12px;
}

/* CTA Cards — replaces pricing tiers with download selling points */
.cta-card {
    align-items: center;
    text-align: center;
    padding: 44px 24px;
}

.cta-icon {
    width: 60px;
    height: 60px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary-subtle);
    color: var(--primary);
    margin-bottom: 22px;
    transition: all var(--transition-base);
}

.cta-card:hover .cta-icon {
    background: var(--primary-glow);
    transform: scale(1.06);
}

.cta-name {
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 10px;
}

.cta-text {
    font-size: 0.88rem;
    color: var(--text-secondary);
    line-height: 1.55;
}

.cta-download {
    display: flex;
    justify-content: center;
    margin-top: 44px;
}

/* ============================================================
   FAQ
   ============================================================ */
.faq-list {
    max-width: 700px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.faq-item {
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    border-radius: var(--radius-md);
    overflow: hidden;
    transition: border-color var(--transition-fast);
}

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

.faq-question {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 18px 20px;
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
    text-align: left;
    transition: color var(--transition-fast);
}

.faq-item.active .faq-question {
    color: var(--primary-light);
}

.faq-arrow {
    flex-shrink: 0;
    transition: transform var(--transition-base);
    color: var(--text-muted);
}

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

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-slow), padding var(--transition-slow);
}

.faq-item.active .faq-answer {
    max-height: 400px;
    padding: 0 20px 18px;
}

.faq-answer p {
    font-size: 0.88rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ============================================================
   CTA
   ============================================================ */
.cta-section {
    padding-bottom: 0;
}

.cta-card {
    text-align: center;
    background: linear-gradient(135deg,
        rgba(43, 143, 255, 0.08),
        rgba(255, 159, 10, 0.05)
    );
    border: 1px solid rgba(43, 143, 255, 0.15);
    border-radius: var(--radius-xl);
    padding: 64px 40px;
    position: relative;
    overflow: hidden;
}

.cta-card::before {
    content: '';
    position: absolute;
    inset: 0;
    background:
        radial-gradient(400px circle at 30% 50%, var(--glow-blue), transparent 60%),
        radial-gradient(300px circle at 70% 50%, var(--glow-orange), transparent 60%);
    opacity: 0.6;
    animation: ctaGlow 6s ease-in-out infinite alternate;
}

@keyframes ctaGlow {
    0% { opacity: 0.4; transform: scale(1); }
    100% { opacity: 0.8; transform: scale(1.05); }
}

.cta-title {
    font-size: clamp(1.6rem, 3.5vw, 2.4rem);
    font-weight: 800;
    margin-bottom: 16px;
    position: relative;
}

.cta-desc {
    font-size: 1.05rem;
    color: var(--text-secondary);
    margin-bottom: 32px;
    position: relative;
}

.cta-card .btn {
    position: relative;
}

.cta-note {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-top: 16px;
    position: relative;
}

/* ============================================================
   Footer
   ============================================================ */
.footer {
    padding: 60px 0 40px;
    border-top: 1px solid var(--border-subtle);
    margin-top: 100px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-logo {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.footer-logo svg {
    color: var(--primary);
}

.footer-tagline {
    font-size: 0.85rem;
    color: var(--text-secondary);
    max-width: 260px;
}

.footer-heading {
    font-size: 0.85rem;
    font-weight: 700;
    margin-bottom: 16px;
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.footer-link {
    display: block;
    font-size: 0.85rem;
    color: var(--text-secondary);
    padding: 4px 0;
    transition: color var(--transition-fast);
}

.footer-link:hover {
    color: var(--text-primary);
}

.footer-bottom {
    border-top: 1px solid var(--border-subtle);
    padding-top: 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.footer-bottom p {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.footer-tech {
    text-align: right;
}

/* ============================================================
   Reveal Animation
   ============================================================ */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.7s var(--ease-out), transform 0.7s var(--ease-out);
}

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

/* ============================================================
   Responsive
   ============================================================ */

/* 1024px */
@media (max-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .why-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: 32px;
    }
    .showcase {
        flex-direction: column;
        gap: 50px;
    }
    .showcase-reverse {
        flex-direction: column;
    }
    .ios-mockup {
        width: 220px;
        border-radius: 38px;
    }
    .ios-screen {
        border-radius: 28px;
    }
    .pricing-grid {
        grid-template-columns: 1fr;
        max-width: 400px;
    }
    .pricing-card-featured {
        transform: none;
    }
    .pricing-card-featured:hover {
        transform: translateY(-4px);
    }
}

/* 768px */
@media (max-width: 768px) {
    .nav-links {
        position: fixed;
        top: var(--nav-height);
        left: 0;
        right: 0;
        background: rgba(10, 10, 15, 0.98);
        backdrop-filter: blur(20px);
        flex-direction: column;
        padding: 16px;
        gap: 4px;
        border-bottom: 1px solid var(--border-subtle);
        transform: translateY(-100%);
        opacity: 0;
        pointer-events: none;
        transition: all var(--transition-base);
    }
    .nav-links.open {
        transform: translateY(0);
        opacity: 1;
        pointer-events: auto;
    }
    .nav-link {
        width: 100%;
        padding: 14px 16px;
    }
    .nav-link::after {
        display: none;
    }
    .nav-toggle {
        display: flex;
    }
    .section {
        padding: 60px 0;
    }
    .section-header {
        margin-bottom: 40px;
    }
    .features-grid {
        grid-template-columns: 1fr;
    }
    .showcase-frame::before {
        width: 250px;
        height: 250px;
    }
    .ios-mockup {
        width: 170px;
        border-radius: 30px;
    }
    .ios-screen {
        border-radius: 22px;
    }
    .ios-mockup::before,
    .ios-mockup::after {
        display: none;
    }
    .steps-grid {
        flex-direction: column;
    }
    .step-card {
        max-width: 100%;
    }
    .step-arrow {
        transform: rotate(90deg);
    }
    .why-grid {
        grid-template-columns: 1fr 1fr;
    }
    .cta-card {
        padding: 40px 24px;
    }
    .footer-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }
    .footer-bottom {
        flex-direction: column;
        gap: 8px;
        text-align: center;
    }
    .footer-tech {
        text-align: center;
    }
    .hero-stat-value {
        font-size: 1.3rem;
    }
    .theme-card {
        flex: 0 0 200px;
    }
    .hide-mobile {
        display: none;
    }
}

/* 480px */
@media (max-width: 480px) {
    .hero-actions {
        flex-direction: column;
        width: 100%;
    }
    .hero-actions .btn {
        width: 100%;
    }
    .showcase-frame::before {
        width: 200px;
        height: 200px;
    }
    .ios-mockup {
        width: 150px;
        border-radius: 26px;
    }
    .ios-screen {
        border-radius: 18px;
    }
    .ios-mockup::before,
    .ios-mockup::after {
        display: none;
    }
    .why-grid {
        grid-template-columns: 1fr;
    }
    .pricing-card {
        padding: 28px 20px;
    }
    .steps-grid {
        gap: 12px;
    }
    .hero-stats {
        gap: 16px;
    }
    .theme-card {
        flex: 0 0 170px;
    }
}