/* ==================== 
   AI Music Card - 暗黑电影感样式 
   ==================== */

:root {
    /* 核心色彩 - 暗黑模式 */
    --bg-primary: #020202;
    --bg-secondary: #0a0a0a;
    --bg-card: #121212;
    
    /* 强调色 */
    --accent-primary: #ffffff;
    --accent-secondary: #888888;
    --accent-glow: rgba(255, 255, 255, 0.15);
    
    /* 渐变 */
    --gradient-primary: linear-gradient(135deg, #1a1a1a 0%, #0a0a0a 100%);
    --gradient-glow: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    
    /* 间距 */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    
    /* 圆角 */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 30px;
    
    /* 动画 */
    --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html, body {
    height: 100%;
    overflow: hidden;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg-primary);
    color: var(--accent-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ==================== 背景层 ==================== */
.bg-layer {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
}

.bg-gradient {
    position: absolute;
    width: 100%;
    height: 100%;
    background: 
        radial-gradient(circle at 20% 80%, rgba(255,255,255,0.03) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(255,255,255,0.05) 0%, transparent 50%),
        radial-gradient(circle at 40% 40%, rgba(255,255,255,0.02) 0%, transparent 40%);
    animation: gradientShift 15s ease-in-out infinite;
}

@keyframes gradientShift {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.8; transform: scale(1.05); }
}

.bg-particles {
    position: absolute;
    width: 100%;
    height: 100%;
    opacity: 0.5;
}

/* ==================== 内容层 ==================== */
.content-layer {
    position: relative;
    z-index: 1;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-lg);
    background: linear-gradient(to bottom, transparent 0%, rgba(0,0,0,0.8) 100%);
}

/* 顶部 Logo */
.top-bar {
    position: absolute;
    top: var(--spacing-md);
    left: 0;
    width: 100%;
    text-align: center;
}

.logo {
    font-size: 0.75rem;
    letter-spacing: 0.3em;
    color: var(--accent-secondary);
    text-transform: uppercase;
    opacity: 0.7;
}

/* ==================== 明信片卡片 ==================== */
.card-container {
    perspective: 1000px;
    margin-bottom: var(--spacing-lg);
}

.music-card {
    width: 280px;
    height: 280px;
    position: relative;
    transform-style: preserve-3d;
    transition: transform var(--transition-slow);
}

.music-card.playing {
    animation: cardFloat 6s ease-in-out infinite;
}

@keyframes cardFloat {
    0%, 100% { transform: translateY(0) rotateX(0); }
    50% { transform: translateY(-10px) rotateX(2deg); }
}

.card-cover {
    width: 100%;
    height: 100%;
    border-radius: var(--radius-lg);
    overflow: hidden;
    position: relative;
    box-shadow: 
        0 25px 50px rgba(0,0,0,0.5),
        0 0 0 1px rgba(255,255,255,0.1);
    background: var(--bg-card);
}

.card-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

.music-card.playing .card-cover img {
    transform: scale(1.05);
}

.card-glow {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--gradient-glow);
    pointer-events: none;
    mix-blend-mode: overlay;
}

/* 音频可视化 */
.visualizer {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 100px;
    opacity: 0;
    transition: opacity var(--transition-base);
}

.music-card.playing .visualizer {
    opacity: 1;
}

#waveform {
    width: 100%;
    height: 100%;
}

#wavePath {
    fill: none;
    stroke: url(#waveGradient);
    stroke-width: 2;
}

/* ==================== 音乐信息 ==================== */
.music-info {
    text-align: center;
    margin-bottom: var(--spacing-lg);
}

.track-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
    background: linear-gradient(135deg, #fff 0%, #888 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.track-artist {
    font-size: 0.875rem;
    color: var(--accent-secondary);
    opacity: 0.7;
}

/* ==================== 播放控制 ==================== */
.controls {
    width: 100%;
    max-width: 320px;
    margin-bottom: var(--spacing-lg);
}

.play-btn {
    width: 64px;
    height: 64px;
    border-radius: 50%;
    border: none;
    background: var(--accent-primary);
    color: var(--bg-primary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto var(--spacing-md);
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
    box-shadow: 0 10px 30px rgba(255,255,255,0.2);
}

.play-btn:hover {
    transform: scale(1.1);
    box-shadow: 0 15px 40px rgba(255,255,255,0.3);
}

.play-btn:active {
    transform: scale(0.95);
}

.play-btn svg {
    width: 24px;
    height: 24px;
    fill: currentColor;
}

/* 进度条 */
.progress-container {
    width: 100%;
}

.progress-bar {
    width: 100%;
    height: 4px;
    background: rgba(255,255,255,0.1);
    border-radius: 2px;
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    width: 0%;
    background: var(--accent-primary);
    border-radius: 2px;
    transition: width 0.1s linear;
    position: relative;
}

.progress-fill::after {
    content: '';
    position: absolute;
    right: -6px;
    top: 50%;
    transform: translateY(-50%);
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--accent-primary);
    box-shadow: 0 2px 10px rgba(255,255,255,0.3);
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.progress-bar:hover .progress-fill::after {
    opacity: 1;
}

.time-display {
    display: flex;
    justify-content: space-between;
    margin-top: var(--spacing-xs);
    font-size: 0.75rem;
    color: var(--accent-secondary);
    opacity: 0.7;
}

/* ==================== 分享按钮 ==================== */
.share-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-lg);
    border: 1px solid rgba(255,255,255,0.2);
    border-radius: var(--radius-xl);
    background: transparent;
    color: var(--accent-primary);
    font-size: 0.875rem;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.share-btn:hover {
    background: rgba(255,255,255,0.1);
    border-color: rgba(255,255,255,0.4);
}

.share-btn svg {
    width: 18px;
    height: 18px;
    fill: currentColor;
}

/* ==================== Loading 遮罩 ==================== */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--bg-primary);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 100;
    transition: opacity var(--transition-slow), visibility var(--transition-slow);
}

.loading-overlay.hidden {
    opacity: 0;
    visibility: hidden;
}

.nfc-pulse {
    position: relative;
    width: 80px;
    height: 80px;
    margin-bottom: var(--spacing-lg);
}

.pulse-ring {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 100%;
    height: 100%;
    border: 2px solid rgba(255,255,255,0.3);
    border-radius: 50%;
    animation: pulse 2s ease-out infinite;
}

.pulse-ring:nth-child(2) {
    animation-delay: 0.4s;
}

.pulse-ring:nth-child(3) {
    animation-delay: 0.8s;
}

@keyframes pulse {
    0% {
        width: 0;
        height: 0;
        opacity: 1;
        border-color: rgba(255,255,255,0.5);
    }
    100% {
        width: 200px;
        height: 200px;
        opacity: 0;
        border-color: rgba(255,255,255,0);
    }
}

.loading-text {
    font-size: 0.875rem;
    color: var(--accent-secondary);
    opacity: 0.7;
    letter-spacing: 0.1em;
}

/* ==================== 响应式 ==================== */
@media (max-width: 480px) {
    .music-card {
        width: 240px;
        height: 240px;
    }
    
    .track-title {
        font-size: 1.25rem;
    }
    
    .play-btn {
        width: 56px;
        height: 56px;
    }
}

/* ==================== 工具类 ==================== */
.glass {
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
}