:root {
    /* 通用 */
    --font-main: 'Segoe UI', sans-serif;
    --transition-speed: 0.3s;
}

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

body {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    font-family: var(--font-main);
    overflow: hidden;
}

.player-container {
    width: 350px;
    height: 600px;
    position: relative;
    border-radius: 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 2rem;
    transition: all var(--transition-speed);
}

.album-cover {
    width: 250px;
    height: 250px;
    border-radius: 50%;
    margin-bottom: 2rem;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    position: relative;
    overflow: hidden;
}

.album-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 50%;
    animation: rotate 10s linear infinite paused;
}

.playing .album-cover img {
    animation-play-state: running;
}

.song-info {
    text-align: center;
    margin-bottom: 2rem;
    width: 100%;
}

.song-title {
    font-size: 1.5rem;
    font-weight: bold;
    margin-bottom: 0.5rem;
}

.artist {
    font-size: 1rem;
    opacity: 0.7;
}

.controls {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 1.5rem;
    width: 100%;
    margin-bottom: 2rem;
}

.btn-control {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1.5rem;
    transition: transform 0.2s;
}

.btn-control:hover {
    transform: scale(1.1);
}

.btn-play {
    font-size: 2.5rem;
}

.progress-container {
    width: 100%;
    height: 5px;
    background: rgba(0,0,0,0.1);
    border-radius: 5px;
    cursor: pointer;
    margin-bottom: 0.5rem;
    position: relative;
}

.progress-bar {
    height: 100%;
    width: 0%;
    background: #333;
    border-radius: 5px;
    transition: width 0.1s linear;
}

.time-info {
    width: 100%;
    display: flex;
    justify-content: space-between;
    font-size: 0.8rem;
    opacity: 0.6;
}

/* 底部导航切换 */
.theme-switcher {
    position: fixed;
    bottom: 2rem;
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    padding: 10px;
    border-radius: 50px;
    display: flex;
    gap: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    z-index: 100;
}

.theme-btn {
    padding: 10px 20px;
    border: none;
    border-radius: 30px;
    background: transparent;
    color: #333;
    cursor: pointer;
    font-weight: bold;
    text-decoration: none;
    transition: all 0.3s;
    font-size: 0.9rem;
}

.theme-btn.active {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

/* =========================================
   STYLE 1: MODERN (Glassmorphism)
   ========================================= */
body.modern {
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
}

.modern .player-container {
    background: rgba(255, 255, 255, 0.25);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.18);
    box-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.15);
}

.modern .album-cover {
    border-radius: 20px;
}

.modern .album-cover img {
    border-radius: 20px;
    animation: none;
}

.modern .btn-control {
    color: #4a4a4a;
}

.modern .btn-play {
    background: #fff;
    width: 60px;
    height: 60px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    color: #6c5ce7;
}

.modern .progress-bar {
    background: linear-gradient(90deg, #6c5ce7, #a29bfe);
}

/* =========================================
   STYLE 2: RETRO (Vinyl / Wood)
   ========================================= */
body.retro {
    background-color: #dcd6c9;
    background-image: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23bcaaa4' fill-opacity='0.2'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
    font-family: 'Courier New', Courier, monospace;
}

.retro .player-container {
    background: #f4e4bc;
    border: 8px solid #8d6e63;
    box-shadow: 10px 10px 0px rgba(0,0,0,0.2);
    border-radius: 5px;
}

.retro .album-cover {
    border: 5px solid #333;
    box-shadow: 0 0 0 2px #f4e4bc, 0 0 0 4px #333;
}

.retro .album-cover::after {
    content: '';
    position: absolute;
    top: 0; left: 0; width: 100%; height: 100%;
    border-radius: 50%;
    background: linear-gradient(45deg, rgba(255,255,255,0) 40%, rgba(255,255,255,0.2) 50%, rgba(255,255,255,0) 60%);
    pointer-events: none;
}

.retro .song-title {
    font-family: 'Georgia', serif;
    color: #5d4037;
    text-transform: uppercase;
    letter-spacing: 2px;
}

.retro .artist {
    color: #8d6e63;
    font-style: italic;
}

.retro .btn-control {
    color: #5d4037;
    border: 2px solid #5d4037;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
}

.retro .btn-play {
    width: 60px;
    height: 60px;
    font-size: 1.5rem;
    background: #5d4037;
    color: #f4e4bc;
}

.retro .progress-container {
    background: #d7ccc8;
    height: 8px;
    border: 1px solid #8d6e63;
}

.retro .progress-bar {
    background: #5d4037;
    border-radius: 0;
}

/* =========================================
   STYLE 3: CYBERPUNK (Neon / Dark)
   ========================================= */
body.cyber {
    background-color: #050505;
    background-image: 
        linear-gradient(rgba(0, 255, 255, 0.05) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 255, 255, 0.05) 1px, transparent 1px);
    background-size: 20px 20px;
    color: #0ff;
    font-family: 'Orbitron', 'Segoe UI', sans-serif;
}

.cyber .player-container {
    background: rgba(0, 0, 0, 0.8);
    border: 2px solid #0ff;
    box-shadow: 0 0 20px rgba(0, 255, 255, 0.3), inset 0 0 20px rgba(0, 255, 255, 0.1);
    clip-path: polygon(0 0, 100% 0, 100% 85%, 90% 100%, 0 100%);
    border-radius: 0;
}

.cyber .album-cover {
    border-radius: 0;
    border: 2px solid #f0f;
    box-shadow: 0 0 15px #f0f;
    position: relative;
}

.cyber .album-cover img {
    border-radius: 0;
    animation: none;
    filter: contrast(1.2) saturate(1.5);
}

.cyber .album-cover::before {
    content: '';
    position: absolute;
    top: 0; left: 0; width: 100%; height: 100%;
    background: linear-gradient(to bottom, transparent 50%, rgba(0, 0, 0, 0.5) 51%);
    background-size: 100% 4px;
    z-index: 2;
    pointer-events: none;
}

.cyber .song-title {
    color: #f0f;
    text-shadow: 2px 2px 0px rgba(0,255,255,0.5);
    letter-spacing: 1px;
}

.cyber .artist {
    color: #0ff;
}

.cyber .btn-control {
    color: #0ff;
    text-shadow: 0 0 5px #0ff;
    border: 1px solid #0ff;
    padding: 10px;
    background: rgba(0, 255, 255, 0.1);
}

.cyber .btn-control:hover {
    background: #0ff;
    color: #000;
    box-shadow: 0 0 15px #0ff;
}

.cyber .btn-play {
    border-color: #f0f;
    color: #f0f;
    text-shadow: 0 0 5px #f0f;
}

.cyber .btn-play:hover {
    background: #f0f;
    color: #000;
    box-shadow: 0 0 15px #f0f;
}

.cyber .progress-container {
    background: #111;
    border: 1px solid #333;
    height: 10px;
}

.cyber .progress-bar {
    background: linear-gradient(90deg, #0ff, #f0f);
    box-shadow: 0 0 10px #0ff;
}

/* =========================================
   STYLE 4: GLASS PRO (Extreme Glassmorphism)
   ========================================= */
body.glass-pro {
    background: #111;
    overflow: hidden;
}

/* 动态背景装饰球 */
.glass-pro .blob-bg {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    z-index: -1;
    overflow: hidden;
}

.glass-pro .blob {
    position: absolute;
    border-radius: 50%;
    filter: blur(60px);
    opacity: 0.8;
    animation: float 10s infinite alternate;
}

.glass-pro .blob:nth-child(1) {
    top: 10%; left: 10%;
    width: 300px; height: 300px;
    background: #ff3cac;
    animation-delay: 0s;
}

.glass-pro .blob:nth-child(2) {
    bottom: 20%; right: 10%;
    width: 350px; height: 350px;
    background: #2b86c5;
    animation-delay: -2s;
}

.glass-pro .blob:nth-child(3) {
    bottom: 10%; left: 30%;
    width: 250px; height: 250px;
    background: #784ba0;
    animation-delay: -4s;
}

.glass-pro .player-container {
    /* 极致玻璃质感 */
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(25px);
    -webkit-backdrop-filter: blur(25px);
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-top: 1px solid rgba(255, 255, 255, 0.5);
    border-left: 1px solid rgba(255, 255, 255, 0.5);
    box-shadow: 
        20px 20px 40px -6px rgba(0,0,0,0.2),
        inset 0 0 0 1px rgba(255,255,255,0.1); /* 内发光 */
    border-radius: 30px;
}

.glass-pro .album-cover {
    border-radius: 20px;
    box-shadow: 0 15px 35px rgba(0,0,0,0.3);
    border: 1px solid rgba(255,255,255,0.2);
}

.glass-pro .album-cover img {
    border-radius: 20px;
    animation: none;
}

/* 玻璃按钮 */
.glass-pro .btn-control {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-top: 1px solid rgba(255, 255, 255, 0.4);
    border-left: 1px solid rgba(255, 255, 255, 0.4);
    box-shadow: 5px 5px 15px rgba(0,0,0,0.1);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
}

.glass-pro .btn-control:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
}

.glass-pro .btn-control:active {
    box-shadow: inset 2px 2px 5px rgba(0,0,0,0.1);
    transform: translateY(0);
}

.glass-pro .btn-play {
    width: 70px;
    height: 70px;
    font-size: 1.8rem;
    background: rgba(255, 255, 255, 0.2);
}

.glass-pro .song-title {
    color: #fff;
    text-shadow: 0 2px 5px rgba(0,0,0,0.2);
}

.glass-pro .artist {
    color: rgba(255, 255, 255, 0.7);
}

.glass-pro .progress-container {
    background: rgba(255, 255, 255, 0.1);
    box-shadow: inset 0 1px 3px rgba(0,0,0,0.2);
    height: 6px;
    border-radius: 10px;
}

.glass-pro .progress-bar {
    background: rgba(255, 255, 255, 0.8);
    box-shadow: 0 0 10px rgba(255, 255, 255, 0.5);
    border-radius: 10px;
}

.glass-pro .time-info {
    color: rgba(255, 255, 255, 0.6);
}

.glass-pro .theme-switcher {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.glass-pro .theme-btn {
    color: rgba(255, 255, 255, 0.8);
}

.glass-pro .theme-btn.active {
    background: rgba(255, 255, 255, 0.3);
    color: #fff;
}

/* 浮动动画 */
@keyframes float {
    0% { transform: translate(0, 0) rotate(0deg); }
    100% { transform: translate(50px, 50px) rotate(20deg); }
}

@keyframes rotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}