/* ========================================
   BabyTune - 十国语言胎教平台
   设计方向：温暖、柔和、母婴友好
   面向：东南亚华人家庭 · 移动优先
   ======================================== */

/* --- CSS 变量 --- */
:root {
    /* 主色调 - 温暖珊瑚粉 */
    --color-primary: #F4845F;
    --color-primary-dark: #E06A45;
    --color-primary-light: #FDE8E0;

    /* 辅助色 */
    --color-secondary: #A78BFA;
    --color-secondary-light: #EDE9FE;
    --color-accent: #FBBF24;
    --color-accent-light: #FEF3C7;

    /* 中性色 */
    --bg-primary: #FFFAF5;
    --bg-secondary: #FFF5ED;
    --bg-card: #FFFFFF;
    --bg-alt: #FDF2F8;

    /* 文字 */
    --text-primary: #3D2C2C;
    --text-secondary: #6B5B5B;
    --text-muted: #9C8C8C;
    --text-inverse: #FFFFFF;

    /* 边框 & 阴影 */
    --border-color: #F0E6DE;
    --shadow-sm: 0 1px 3px rgba(61, 44, 44, 0.06);
    --shadow-md: 0 4px 12px rgba(61, 44, 44, 0.08);
    --shadow-lg: 0 10px 30px rgba(61, 44, 44, 0.1);

    /* 圆角 */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 28px;

    /* 字体 */
    --font-sans: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-serif: 'Noto Serif SC', Georgia, serif;

    /* 布局 */
    --max-width: 1200px;
    --header-height: 72px;
    --player-height: 72px;

    /* 过渡 */
    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* --- 重置 --- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--font-sans);
    color: var(--text-primary);
    background: var(--bg-primary);
    line-height: 1.7;
    min-height: 100vh;
    padding-top: var(--header-height);
    padding-bottom: var(--player-height);
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
}

/* --- 排版 --- */
h1, h2, h3, h4 {
    font-family: var(--font-serif);
    font-weight: 700;
    line-height: 1.3;
}

h1 { font-size: clamp(2rem, 5vw, 3.2rem); }
h2 { font-size: clamp(1.5rem, 4vw, 2.2rem); }
h3 { font-size: clamp(1.1rem, 3vw, 1.4rem); }
h4 { font-size: 1.05rem; }

a {
    color: var(--color-primary);
    text-decoration: none;
    transition: color var(--transition);
}
a:hover { color: var(--color-primary-dark); }

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

/* --- 按钮 --- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 28px;
    border-radius: var(--radius-xl);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition);
    border: 2px solid transparent;
    font-family: var(--font-sans);
}

.btn-primary {
    background: var(--color-primary);
    color: var(--text-inverse);
}
.btn-primary:hover {
    background: var(--color-primary-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
    color: var(--text-inverse);
}

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

/* ========================================
   顶部导航
   ======================================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background: rgba(255, 250, 245, 0.92);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-primary);
    font-weight: 700;
    font-size: 1.3rem;
    font-family: var(--font-serif);
}
.logo-icon { font-size: 1.6rem; }
.logo:hover { color: var(--color-primary); }

.nav {
    display: flex;
    align-items: center;
    gap: 8px;
}
.nav a {
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
    font-size: 0.95rem;
    transition: all var(--transition);
}
.nav a:hover {
    background: var(--color-primary-light);
    color: var(--color-primary-dark);
}

/* --- 语言切换器 --- */
.header-actions {
    display: flex;
    align-items: center;
    gap: 12px;
}

.lang-switcher { position: relative; }

.lang-btn {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 8px 14px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 0.9rem;
    color: var(--text-primary);
    transition: all var(--transition);
}
.lang-btn:hover {
    border-color: var(--color-primary);
    background: var(--color-primary-light);
}

.lang-dropdown {
    display: none;
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    width: 260px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    padding: 8px;
    z-index: 100;
}
.lang-dropdown.open { display: block; }

.lang-dropdown-grid {
    display: grid;
    gap: 2px;
}
.lang-dropdown-grid a {
    display: block;
    padding: 10px 14px;
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-size: 0.92rem;
    transition: background var(--transition);
}
.lang-dropdown-grid a:hover,
.lang-dropdown-grid a.active {
    background: var(--color-primary-light);
    color: var(--color-primary-dark);
    font-weight: 500;
}

/* 移动端菜单按钮 */
.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}
.menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: all var(--transition);
}

/* ========================================
   Hero 区域
   ======================================== */
.hero {
    position: relative;
    background: linear-gradient(135deg, #FFF5ED 0%, #FDE8E0 30%, #EDE9FE 70%, #FFF5ED 100%);
    padding: 80px 0 0;
    overflow: hidden;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    min-height: 460px;
}

.hero-badge {
    display: inline-block;
    padding: 6px 18px;
    background: var(--color-primary-light);
    color: var(--color-primary-dark);
    border-radius: var(--radius-xl);
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: 20px;
}

.hero-title {
    margin-bottom: 16px;
}
.hero-highlight {
    display: block;
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    color: var(--text-secondary);
    font-size: 1.1rem;
    line-height: 1.8;
    margin-bottom: 32px;
    max-width: 480px;
}

.hero-actions {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
    margin-bottom: 40px;
}

.hero-stats {
    display: flex;
    gap: 32px;
}

.stat {
    display: flex;
    flex-direction: column;
}
.stat-number {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--color-primary);
    font-family: var(--font-serif);
}
.stat-label {
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* Hero 视觉元素 */
.hero-visual {
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-illustration {
    position: relative;
    width: 260px;
    height: 260px;
}

.hero-circle {
    width: 100%;
    height: 100%;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--color-primary-light), var(--bg-card));
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-lg);
}
.hero-emoji {
    font-size: 5rem;
    animation: gentle-bounce 3s ease-in-out infinite;
}

@keyframes gentle-bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-8px); }
}

.floating-notes .note {
    position: absolute;
    font-size: 1.8rem;
    opacity: 0.4;
    animation: float 4s ease-in-out infinite;
}
.note-1 { top: 10px; left: -20px; animation-delay: 0s; }
.note-2 { top: 30px; right: -10px; animation-delay: 0.6s; }
.note-3 { bottom: 20px; left: 10px; animation-delay: 1.2s; }
.note-4 { bottom: 50px; right: -30px; animation-delay: 1.8s; }
.note-5 { top: 50%; left: -40px; animation-delay: 2.4s; }

@keyframes float {
    0%, 100% { transform: translateY(0) rotate(0deg); opacity: 0.4; }
    50% { transform: translateY(-15px) rotate(10deg); opacity: 0.7; }
}

.hero-wave {
    margin-top: -1px;
    line-height: 0;
}
.hero-wave svg {
    display: block;
    width: 100%;
    height: 80px;
}

/* ========================================
   通用区块
   ======================================== */
section {
    padding: 80px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 48px;
}
.section-header h2 {
    margin-bottom: 12px;
}
.section-header p {
    color: var(--text-secondary);
    font-size: 1.05rem;
}

.section-tag {
    display: inline-block;
    padding: 6px 16px;
    background: var(--color-accent-light);
    color: var(--text-primary);
    border-radius: var(--radius-xl);
    font-size: 0.85rem;
    font-weight: 500;
    margin-bottom: 16px;
}

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

/* ========================================
   功能卡片
   ======================================== */
.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 24px;
}

.feature-card {
    background: var(--bg-card);
    padding: 32px 24px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    text-align: center;
    transition: all var(--transition);
}
.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}
.feature-icon {
    font-size: 2.8rem;
    margin-bottom: 16px;
}
.feature-card h3 {
    font-family: var(--font-sans);
    margin-bottom: 8px;
}
.feature-card p {
    color: var(--text-secondary);
    font-size: 0.92rem;
    line-height: 1.6;
}

/* ========================================
   音乐卡片
   ======================================== */
.music-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
}

.music-card {
    display: flex;
    align-items: center;
    gap: 16px;
    background: var(--bg-card);
    padding: 20px;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition);
}
.music-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.music-cover {
    width: 64px;
    height: 64px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    flex-shrink: 0;
}
.cover-1 { background: #FDE8E0; }
.cover-2 { background: #DBEAFE; }
.cover-3 { background: #D1FAE5; }
.cover-4 { background: #EDE9FE; }
.cover-5 { background: #FEF3C7; }
.cover-6 { background: #FCE7F3; }

.music-info {
    flex: 1;
    min-width: 0;
}
.music-info h4 {
    font-family: var(--font-sans);
    font-size: 0.95rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.music-info p {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-top: 2px;
}
.music-tag {
    display: inline-block;
    padding: 2px 10px;
    background: var(--color-primary-light);
    color: var(--color-primary-dark);
    border-radius: var(--radius-sm);
    font-size: 0.72rem;
    margin-top: 6px;
}

.play-btn {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: none;
    background: var(--color-primary);
    color: white;
    font-size: 1rem;
    cursor: pointer;
    flex-shrink: 0;
    transition: all var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}
.play-btn:hover {
    background: var(--color-primary-dark);
    transform: scale(1.08);
}
.play-btn.playing {
    background: var(--color-secondary);
}

/* ========================================
   故事区
   ======================================== */
.story-showcase {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    align-items: start;
}

.story-card {
    background: var(--bg-card);
    padding: 32px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
}

.story-featured {
    background: linear-gradient(135deg, #EDE9FE, #FDF2F8);
}

.story-badge {
    display: inline-block;
    padding: 4px 14px;
    background: var(--color-secondary-light);
    color: var(--color-secondary);
    border-radius: var(--radius-xl);
    font-size: 0.8rem;
    font-weight: 500;
    margin-bottom: 16px;
}

.story-featured h3 {
    margin-bottom: 8px;
}
.story-featured p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 16px;
    line-height: 1.7;
}

.story-langs {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 20px;
}
.story-langs span {
    padding: 4px 12px;
    background: white;
    border-radius: var(--radius-sm);
    font-size: 0.82rem;
    color: var(--text-secondary);
}

.story-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.story-item {
    display: flex;
    align-items: center;
    gap: 14px;
    background: var(--bg-card);
    padding: 16px 20px;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    cursor: pointer;
    transition: all var(--transition);
}
.story-item:hover {
    transform: translateX(4px);
    box-shadow: var(--shadow-md);
}
.story-emoji {
    font-size: 1.5rem;
}
.story-item h4 {
    font-family: var(--font-sans);
    font-size: 0.95rem;
}
.story-item p {
    font-size: 0.8rem;
    color: var(--text-muted);
}
.story-langs-mini {
    margin-left: auto;
    padding: 4px 10px;
    background: var(--color-accent-light);
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    color: var(--text-primary);
    font-weight: 500;
    white-space: nowrap;
}

/* ========================================
   语言展示
   ======================================== */
.languages-section {
    background: var(--bg-alt);
}

.lang-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 16px;
}

.lang-card {
    background: var(--bg-card);
    padding: 24px 20px;
    border-radius: var(--radius-md);
    text-align: center;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition);
}
.lang-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
}
.lang-flag {
    font-size: 2.2rem;
    display: block;
    margin-bottom: 10px;
}
.lang-card h4 {
    font-family: var(--font-sans);
    font-size: 0.95rem;
    margin-bottom: 4px;
}
.lang-card p {
    font-size: 0.8rem;
    color: var(--text-muted);
}

/* ========================================
   关于我们
   ======================================== */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: start;
}

.about-content h2 {
    margin-bottom: 20px;
}
.about-content p {
    color: var(--text-secondary);
    margin-bottom: 16px;
    line-height: 1.8;
}
.about-contact {
    margin-top: 24px;
    padding: 12px 20px;
    background: var(--color-primary-light);
    border-radius: var(--radius-md);
    color: var(--color-primary-dark);
    font-weight: 500;
}

.about-values {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.value-item {
    display: flex;
    gap: 16px;
    align-items: flex-start;
}
.value-item span {
    font-size: 2rem;
    flex-shrink: 0;
    margin-top: -4px;
}
.value-item h4 {
    font-family: var(--font-sans);
    margin-bottom: 4px;
}
.value-item p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* ========================================
   底部音频播放器
   ======================================== */
.audio-player {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    height: var(--player-height);
    background: var(--bg-card);
    border-top: 1px solid var(--border-color);
    box-shadow: 0 -2px 12px rgba(0,0,0,0.05);
    z-index: 999;
}

.player-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
    gap: 20px;
}

.player-info {
    display: flex;
    align-items: center;
    gap: 12px;
    flex: 1;
    min-width: 0;
}
.player-cover {
    font-size: 1.8rem;
}
.player-title {
    font-size: 0.9rem;
    font-weight: 500;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.player-artist {
    font-size: 0.78rem;
    color: var(--text-muted);
}

.player-controls {
    display: flex;
    align-items: center;
    gap: 8px;
}
.player-btn {
    width: 36px;
    height: 36px;
    border: none;
    background: none;
    cursor: pointer;
    border-radius: 50%;
    font-size: 1rem;
    transition: background var(--transition);
}
.player-btn:hover { background: var(--color-primary-light); }
.player-btn-play {
    width: 48px;
    height: 48px;
    background: var(--color-primary);
    color: white;
}
.player-btn-play:hover { background: var(--color-primary-dark); }

.player-volume {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.9rem;
}
.volume-slider {
    width: 80px;
    accent-color: var(--color-primary);
}

/* ========================================
   页脚
   ======================================== */
.footer {
    background: var(--text-primary);
    color: var(--text-inverse);
    padding: 60px 0 32px;
}

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

.footer-brand p {
    color: rgba(255,255,255,0.6);
    margin-top: 12px;
    font-size: 0.9rem;
}

.footer-links h4 {
    font-family: var(--font-sans);
    font-size: 0.9rem;
    margin-bottom: 16px;
    color: rgba(255,255,255,0.7);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}
.footer-links a {
    display: block;
    color: rgba(255,255,255,0.5);
    font-size: 0.88rem;
    padding: 4px 0;
    transition: color var(--transition);
}
.footer-links a:hover {
    color: var(--color-primary-light);
}

.footer-bottom {
    padding-top: 24px;
    border-top: 1px solid rgba(255,255,255,0.1);
    text-align: center;
    font-size: 0.85rem;
    color: rgba(255,255,255,0.4);
}

/* ========================================
   响应式 - 平板
   ======================================== */
@media (max-width: 900px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 40px;
    }
    .hero-subtitle { max-width: 100%; }
    .hero-actions { justify-content: center; }
    .hero-stats { justify-content: center; }
    .hero-visual { order: -1; }
    .hero-illustration { width: 200px; height: 200px; }
    .hero-emoji { font-size: 4rem; }

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

/* ========================================
   响应式 - 手机
   ======================================== */
@media (max-width: 640px) {
    :root {
        --header-height: 60px;
    }

    .container { padding: 0 16px; }

    .nav {
        display: none;
        position: fixed;
        top: var(--header-height);
        left: 0;
        right: 0;
        background: var(--bg-card);
        border-bottom: 1px solid var(--border-color);
        flex-direction: column;
        padding: 16px;
        box-shadow: var(--shadow-md);
    }
    .nav.open { display: flex; }
    .nav a {
        padding: 12px 16px;
        width: 100%;
    }

    .menu-toggle { display: flex; }

    .hero {
        padding: 40px 0 0;
    }
    .hero-title { font-size: 1.8rem; }
    .hero-subtitle { font-size: 0.95rem; }
    .hero-actions { flex-direction: column; }
    .hero-actions .btn { width: 100%; justify-content: center; }
    .hero-stats { gap: 20px; }
    .stat-number { font-size: 1.4rem; }

    section { padding: 48px 0; }
    .section-header { margin-bottom: 32px; }

    .feature-grid { grid-template-columns: 1fr; }
    .music-grid { grid-template-columns: 1fr; }

    .lang-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 10px;
    }
    .lang-card { padding: 18px 14px; }

    .footer-grid { grid-template-columns: 1fr; gap: 24px; }

    .player-volume .volume-slider { width: 50px; }
}