/* ========================================
   SECTION 3: SONGS - 歌曲创作展示（音频卡片风格）
   ======================================== */
.section-songs {
    background: var(--color-bg-primary);
    flex-direction: column;
    align-items: flex-start;
    justify-content: flex-start;
    padding-top: calc(var(--nav-height) + var(--spacing-md));
    position: relative;
    overflow: hidden;
}

/* Songs 装饰 */
.songs-bg-decoration {
    background-image: 
        radial-gradient(circle, rgba(201, 169, 97, 0.2) 2.5px, transparent 2.5px),
        radial-gradient(circle, rgba(201, 169, 97, 0.12) 1.5px, transparent 1.5px);
    background-size: 60px 60px, 30px 30px;
    background-position: 0 0, 30px 30px;
    opacity: 0.5;
}

.songs-bg-decoration::before {
    content: '';
    position: absolute;
    bottom: 5%;
    left: -8%;
    width: 700px;
    height: 500px;
    background: radial-gradient(
        ellipse at center,
        rgba(201, 169, 97, 0.18) 0%,
        rgba(201, 169, 97, 0.1) 40%,
        transparent 70%
    );
    filter: blur(100px);
}

.songs-bg-decoration::after {
    content: '';
    position: absolute;
    top: 15%;
    right: -10%;
    width: 500px;
    height: 500px;
    background: radial-gradient(
        circle at center,
        rgba(201, 169, 97, 0.12) 0%,
        transparent 65%
    );
    filter: blur(70px);
}

/* 歌曲容器 - 每个卡片占一行 */
.songs-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
    position: relative;
    z-index: 1;
}

/* 卡片基础样式 - 横向布局 */
.song-card {
    display: flex;
    flex-direction: row;
    align-items: stretch;
    gap: var(--spacing-xl);
    background: var(--color-bg-elevated);
    border: var(--border-thin);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    position: relative;
    overflow: hidden;
    box-sizing: border-box;
    transition: all var(--transition-normal);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

/* 精致的顶部高光线 */
.song-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--color-accent-gold), transparent);
    opacity: 0;
    transition: opacity var(--transition-normal);
    z-index: 1;
}

.song-card:hover {
    border-color: rgba(201, 169, 97, 0.4);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3), 0 0 0 1px rgba(201, 169, 97, 0.1);
    transform: translateY(-2px);
}

.theme-light .song-card:hover {
    border-color: rgba(166, 124, 61, 0.3);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1), 0 0 0 1px rgba(166, 124, 61, 0.15);
}

.song-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 2px;
    background: var(--color-accent-gold);
    transition: width 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: 2;
}

.song-card:hover::before,
.song-card.playing::before {
    opacity: 0.8;
}

.song-card:hover::after,
.song-card.playing::after {
    width: 120px;
}

.song-card.playing {
    border-color: var(--color-accent-gold);
    box-shadow: 0 8px 32px rgba(201, 169, 97, 0.2), 0 0 0 1px rgba(201, 169, 97, 0.2);
}

.song-card.playing::before {
    opacity: 1;
    animation: shimmer 3s ease-in-out infinite;
}

@keyframes shimmer {
    0%, 100% {
        background: linear-gradient(90deg, transparent, var(--color-accent-gold), transparent);
    }
    50% {
        background: linear-gradient(90deg, transparent, rgba(201, 169, 97, 0.6), transparent);
    }
}

/* 卡片左侧内容区域 */
.song-card-left {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-width: 0;
    justify-content: space-between;
    padding-right: var(--spacing-md);
}

/* 卡片头部 */
.song-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-shrink: 0;
    margin-bottom: var(--spacing-lg);
    position: relative;
    z-index: 1;
}

.song-card-category {
    font-size: 0.75rem;
    letter-spacing: 0.4em;
    text-transform: uppercase;
    color: var(--color-text-muted);
    font-family: var(--font-sans);
    font-weight: 500;
    position: relative;
    padding-left: var(--spacing-md);
    transition: color var(--transition-fast);
}

.song-card:hover .song-card-category {
    color: var(--color-text-secondary);
}

.song-card-category::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 4px;
    height: 14px;
    background: var(--color-accent-gold);
    opacity: 0.5;
    transition: all var(--transition-fast);
    border-radius: 2px;
}

.song-card:hover .song-card-category::before,
.song-card.playing .song-card-category::before {
    opacity: 1;
    height: 16px;
    box-shadow: 0 0 8px rgba(201, 169, 97, 0.4);
}

.song-card-meta {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.song-card-duration {
    font-size: 0.8125rem;
    color: var(--color-text-muted);
    letter-spacing: 0.15em;
    font-weight: 400;
    font-family: var(--font-sans);
}

/* 卡片内容区域 */
.song-card-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    position: relative;
    z-index: 1;
    justify-content: center;
}

.song-card-title {
    font-size: 1.75rem;
    font-family: var(--font-serif);
    font-weight: 400;
    color: var(--color-text-primary);
    margin: 0;
    line-height: 1.4;
    transition: all var(--transition-fast);
    letter-spacing: 0.02em;
}

.song-card:hover .song-card-title {
    color: var(--color-text-primary);
}

.song-card.playing .song-card-title {
    color: var(--color-accent-gold);
}

.theme-light .song-card.playing .song-card-title {
    color: var(--color-accent-gold);
    text-shadow: 0 1px 3px rgba(166, 124, 61, 0.2);
}

.song-card-desc {
    font-size: 1rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
    margin: 0;
    position: relative;
    padding-left: calc(var(--spacing-md) + 0.75rem);
    max-width: 90%;
}

.song-card-desc::before {
    content: '—';
    position: absolute;
    left: 0;
    top: 0;
    color: var(--color-text-muted);
    opacity: 0.4;
    font-size: 1.2em;
    line-height: 1.7;
    transition: opacity var(--transition-fast);
}

.song-card:hover .song-card-desc::before {
    opacity: 0.6;
}

/* 音频控制区域 - 右侧 */
.song-card-audio {
    flex-shrink: 0;
    width: 380px;
    min-width: 340px;
    opacity: 0.7;
    transition: all var(--transition-normal);
    box-sizing: border-box;
    display: flex;
    align-items: center;
    position: relative;
}

.song-card:hover .song-card-audio,
.song-card.playing .song-card-audio {
    opacity: 1;
}

/* YouTube iframe - minimum size player */
.youtube-audio-wrapper {
    width: 100%;
    height: 214px;
    position: relative;
    border-radius: var(--radius-md);
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-line);
    transition: all var(--transition-fast);
    overflow: hidden;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
}

.song-card:hover .youtube-audio-wrapper {
    border-color: rgba(201, 169, 97, 0.4);
    box-shadow: 0 6px 24px rgba(0, 0, 0, 0.15), 0 0 0 1px rgba(201, 169, 97, 0.1);
    transform: scale(1.01);
}

.song-card.playing .youtube-audio-wrapper {
    border-color: rgba(201, 169, 97, 0.5);
    box-shadow: 0 8px 32px rgba(201, 169, 97, 0.15), 0 0 0 1px rgba(201, 169, 97, 0.2);
}

.youtube-audio-player {
    width: 100%;
    height: 100%;
    border: none;
    display: block;
}

/* 响应式 - 平板 */
@media (max-width: 1024px) {
    .song-card {
        gap: var(--spacing-lg);
        padding: var(--spacing-lg);
    }
    
    .song-card-left {
        padding-right: var(--spacing-sm);
    }
    
    .song-card-audio {
        width: 340px;
        min-width: 300px;
    }
    
    .youtube-audio-wrapper {
        height: 191px;
    }
    
    .song-card-title {
        font-size: 1.5rem;
    }
}

/* 响应式 - 移动端改为纵向布局 */
@media (max-width: 768px) {
    .songs-container {
        gap: var(--spacing-md);
        padding: 0 var(--spacing-sm);
    }

    .song-card {
        flex-direction: column;
        padding: var(--spacing-lg);
        gap: var(--spacing-lg);
    }
    
    .song-card-left {
        width: 100%;
        padding-right: 0;
    }
    
    .song-card-header {
        margin-bottom: var(--spacing-md);
    }
    
    .song-card-content {
        margin-bottom: 0;
        gap: var(--spacing-sm);
    }
    
    .song-card-desc {
        max-width: 100%;
    }

    .song-card-audio {
        width: 100%;
        min-width: auto;
        padding-top: var(--spacing-md);
        border-top: 1px solid var(--color-line);
        opacity: 1;
    }
    
    .song-card:hover .song-card-audio,
    .song-card.playing .song-card-audio {
        border-top-color: rgba(201, 169, 97, 0.3);
    }

    .youtube-audio-wrapper {
        height: 200px;
    }

    .song-card-title {
        font-size: 1.375rem;
    }
    
    .song-card-desc {
        font-size: 0.9375rem;
    }
}

@media (max-width: 480px) {
    .song-card {
        padding: var(--spacing-md);
        gap: var(--spacing-md);
    }
    
    .song-card-header {
        margin-bottom: var(--spacing-sm);
    }

    .song-card-title {
        font-size: 1.25rem;
    }

    .song-card-desc {
        font-size: 0.875rem;
        padding-left: calc(var(--spacing-sm) + 0.5rem);
    }
    
    .youtube-audio-wrapper {
        height: 180px;
        border-radius: var(--radius-sm);
    }
}