/* Material You (Material Design 3) 颜色系统 */
:root {
    /* 主色调 */
    --md-sys-color-primary: #6750A4;
    --md-sys-color-on-primary: #FFFFFF;
    --md-sys-color-primary-container: #EADDFF;
    --md-sys-color-on-primary-container: #21005D;

    /* 次色调 */
    --md-sys-color-secondary: #625B71;
    --md-sys-color-on-secondary: #FFFFFF;
    --md-sys-color-secondary-container: #E8DEF8;
    --md-sys-color-on-secondary-container: #1D192B;

    /* 表面色 */
    --md-sys-color-surface: #FEF7FF;
    --md-sys-color-on-surface: #1D1B20;
    --md-sys-color-surface-variant: #E7E0EC;
    --md-sys-color-on-surface-variant: #49454F;

    /* 背景色 */
    --md-sys-color-background: #FEF7FF;
    --md-sys-color-on-background: #1D1B20;

    /* 错误色 */
    --md-sys-color-error: #B3261E;
    --md-sys-color-on-error: #FFFFFF;
    --md-sys-color-error-container: #F9DEDC;
    --md-sys-color-on-error-container: #410E0B;

    /* 轮廓色 */
    --md-sys-color-outline: #79747E;
    --md-sys-color-outline-variant: #CAC4D0;

    /* 表面容器层级 */
    --md-sys-color-surface-container-low: #F7F2FA;
    --md-sys-color-surface-container: #F3EDF7;
    --md-sys-color-surface-container-high: #ECE6F0;
    --md-sys-color-surface-variant: #E7E0EC;

    /* 阴影 */
    --md-sys-elevation-1: 0 1px 3px rgba(0,0,0,0.12), 0 1px 2px rgba(0,0,0,0.08);
    --md-sys-elevation-2: 0 2px 6px rgba(0,0,0,0.15), 0 1px 3px rgba(0,0,0,0.10);
    --md-sys-elevation-3: 0 4px 12px rgba(0,0,0,0.18), 0 2px 6px rgba(0,0,0,0.12);
    --md-sys-elevation-4: 0 8px 24px rgba(0,0,0,0.20), 0 4px 12px rgba(0,0,0,0.15);

    /* 圆角 */
    --md-sys-corner-small: 8px;
    --md-sys-corner-medium: 12px;
    --md-sys-corner-large: 16px;
    --md-sys-corner-extra-large: 28px;
    --md-sys-corner-full: 9999px;

    /* 非线性动画缓动函数 */
    --md-sys-motion-easing-emphasized: cubic-bezier(0.2, 0, 0, 1);
    --md-sys-motion-easing-emphasized-decelerate: cubic-bezier(0.05, 0.7, 0.1, 1);
    --md-sys-motion-easing-emphasized-accelerate: cubic-bezier(0.3, 0, 0.8, 0.15);
    --md-sys-motion-easing-standard: cubic-bezier(0.2, 0, 0, 1);
    --md-sys-motion-easing-legacy: cubic-bezier(0.4, 0, 0.2, 1);
    --md-sys-motion-easing-legacy-accelerate: cubic-bezier(0.4, 0, 1, 1);
    --md-sys-motion-easing-legacy-decelerate: cubic-bezier(0, 0, 0.2, 1);

    /* 动画时长 */
    --md-sys-motion-duration-short1: 200ms;
    --md-sys-motion-duration-short2: 300ms;
    --md-sys-motion-duration-short3: 400ms;
    --md-sys-motion-duration-short4: 500ms;
    --md-sys-motion-duration-medium1: 600ms;
    --md-sys-motion-duration-medium2: 700ms;
    --md-sys-motion-duration-long1: 900ms;
    --md-sys-motion-duration-long2: 1100ms;
}

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

*:focus {
    outline: none;
}

button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
    outline: none;
}

body {
    font-family: 'Google Sans', 'Noto Sans SC', system-ui, -apple-system, sans-serif;
    background-color: var(--md-sys-color-background);
    color: var(--md-sys-color-on-background);
    line-height: 1.5;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
}

/* ========== 顶部应用栏 ========== */
.top-app-bar {
    background-color: var(--md-sys-color-surface);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--md-sys-elevation-1);
    backdrop-filter: blur(8px);
    background: linear-gradient(180deg, var(--md-sys-color-surface) 0%, rgba(254, 247, 255, 0.9) 100%);
}

.app-bar-content {
    max-width: 800px;
    margin: 0 auto;
    padding: 16px 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.app-title {
    font-family: 'Google Sans Display', 'Noto Sans SC', sans-serif;
    font-size: 24px;
    font-weight: 500;
    color: var(--md-sys-color-on-surface);
    letter-spacing: -0.5px;
}

.app-logo {
    font-size: 28px;
    animation: float 3s ease-in-out infinite;
    display: flex;
    align-items: center;
    justify-content: center;
}

.app-logo .material-icons-round {
    font-size: 32px;
}

@keyframes float {
    0%, 100% { margin-top: 0; }
    50% { margin-top: -4px; }
}

/* ========== 主内容区域 ========== */
.main-content {
    flex: 1;
    max-width: 800px;
    width: 100%;
    margin: 0 auto;
    padding: 24px 20px;
    padding-bottom: 80px;
    overflow-x: hidden;
}

.page {
    display: none;
    animation: pageEnter var(--md-sys-motion-duration-short4) var(--md-sys-motion-easing-emphasized-decelerate);
}

.page.active {
    display: block;
}

@keyframes pageEnter {
    from {
        opacity: 0;
        transform: translateY(20px) scale(0.98);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

.page-header {
    margin-bottom: 24px;
    padding: 0 8px;
}

.page-header h2 {
    font-size: 28px;
    font-weight: 500;
    color: var(--md-sys-color-on-surface);
    margin-bottom: 4px;
    letter-spacing: -0.5px;
}

.page-subtitle {
    font-size: 14px;
    color: var(--md-sys-color-on-surface-variant);
}

/* ========== 平台选择器 ========== */
.platform-selector {
    display: flex;
    gap: 12px;
    margin-bottom: 24px;
    padding: 0 8px;
}

.platform-chip {
    flex: 1;
    padding: 12px 20px;
    background-color: var(--md-sys-color-surface-container);
    border: 2px solid transparent;
    border-radius: var(--md-sys-corner-large);
    font-size: 14px;
    font-weight: 500;
    color: var(--md-sys-color-on-surface-variant);
    cursor: pointer;
    transition: all var(--md-sys-motion-duration-short3) var(--md-sys-motion-easing-emphasized-decelerate);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    position: relative;
    overflow: hidden;
}

.platform-chip::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background-color: var(--md-sys-color-primary);
    opacity: 0.1;
    transform: translate(-50%, -50%);
    transition: width var(--md-sys-motion-duration-medium1) var(--md-sys-motion-easing-emphasized-decelerate),
                height var(--md-sys-motion-duration-medium1) var(--md-sys-motion-easing-emphasized-decelerate);
}

.platform-chip:hover::before {
    width: 200%;
    height: 200%;
}

.platform-chip:hover {
    background-color: var(--md-sys-color-surface-container-high);
    transform: translateY(-2px);
    box-shadow: var(--md-sys-elevation-1);
}

.platform-chip:active {
    transform: translateY(0) scale(0.98);
}

.platform-chip.active {
    background-color: var(--md-sys-color-primary-container);
    color: var(--md-sys-color-on-primary-container);
    border-color: var(--md-sys-color-primary);
    transform: scale(1.02);
}

.platform-chip.active:hover {
    transform: scale(1.05);
}

.platform-icon {
    display: flex;
    align-items: center;
}

.platform-icon.material-icons-round {
    font-size: 20px;
}

.search-section {
    display: none;
}

.search-section.active {
    display: block;
    animation: fadeIn var(--md-sys-motion-duration-short3) var(--md-sys-motion-easing-emphasized-decelerate);
}

/* ========== 导入方式选择器 ========== */
.import-type-selector {
    display: flex;
    gap: 8px;
    width: 100%;
}

.import-type-chip {
    flex: 1;
    padding: 10px 16px;
    background-color: var(--md-sys-color-surface-container);
    border: 2px solid transparent;
    border-radius: var(--md-sys-corner-large);
    font-size: 13px;
    font-weight: 500;
    color: var(--md-sys-color-on-surface-variant);
    cursor: pointer;
    transition: all 0.3s var(--md-sys-motion-easing);
}

.import-type-chip:hover {
    background-color: var(--md-sys-color-surface-container-high);
}

.import-type-chip.active {
    background-color: var(--md-sys-color-primary-container);
    color: var(--md-sys-color-on-primary-container);
    border-color: var(--md-sys-color-primary);
}

.import-section {
    display: none;
}

.import-section.active {
    display: block;
    animation: fadeIn var(--md-sys-motion-duration-short3) var(--md-sys-motion-easing-emphasized-decelerate);
}

@keyframes fadeIn {
    from { 
        opacity: 0;
        transform: scale(0.95);
    }
    to { 
        opacity: 1;
        transform: scale(1);
    }
}

/* ========== 更多动画关键帧 ========== */

/* 弹性缩放动画 */
@keyframes elasticScale {
    0% { transform: scale(1); }
    30% { transform: scale(1.05); }
    50% { transform: scale(0.98); }
    70% { transform: scale(1.02); }
    100% { transform: scale(1); }
}

/* 模糊进入动画 */
@keyframes blurIn {
    from {
        opacity: 0;
        filter: blur(8px);
        transform: translateY(8px);
    }
    to {
        opacity: 1;
        filter: blur(0);
        transform: translateY(0);
    }
}

/* 弹跳动画 */
@keyframes bounce {
    0%, 100% { 
        transform: translateY(0);
        animation-timing-function: cubic-bezier(0.8, 0, 1, 1);
    }
    50% { 
        transform: translateY(-8px);
        animation-timing-function: cubic-bezier(0, 0, 0.2, 1);
    }
}

/* 发光动画 */
@keyframes glow {
    0%, 100% { 
        box-shadow: 0 0 5px var(--md-sys-color-primary);
    }
    50% { 
        box-shadow: 0 0 20px var(--md-sys-color-primary);
    }
}

/* 摇晃动画 */
@keyframes shake {
    0%, 100% { transform: translateX(0); }
    10%, 30%, 50%, 70%, 90% { transform: translateX(-3px); }
    20%, 40%, 60%, 80% { transform: translateX(3px); }
}

/* 进度条条纹动画 */
@keyframes progressStripes {
    from { background-position: 40px 0; }
    to { background-position: 0 0; }
}

/* 缩放进入动画 */
@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.8);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

/* ========== 卡片 ========== */
.card {
    background-color: var(--md-sys-color-surface-container);
    border-radius: var(--md-sys-corner-extra-large);
    margin-bottom: 20px;
    overflow: hidden;
    box-shadow: var(--md-sys-elevation-1);
    transition: box-shadow 0.3s var(--md-sys-motion-easing);
}

.card:hover {
    box-shadow: var(--md-sys-elevation-2);
}

.card-header {
    padding: 20px 24px;
    border-bottom: 1px solid var(--md-sys-color-outline-variant);
}

.card-header h3 {
    font-size: 18px;
    font-weight: 500;
    color: var(--md-sys-color-on-surface);
}

.card-content {
    padding: 20px 24px;
}

/* ========== 输入框 ========== */
.input-wrapper {
    position: relative;
    margin-bottom: 16px;
}

.search-icon,
.input-icon {
    position: absolute;
    left: 16px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--md-sys-color-on-surface-variant);
    pointer-events: none;
    display: flex;
    align-items: center;
    transition: color var(--md-sys-motion-duration-short3) var(--md-sys-motion-easing-emphasized-decelerate);
    z-index: 1;
}

.search-input:focus ~ .search-icon {
    color: var(--md-sys-color-on-primary-container);
}

.search-icon.material-icons-round,
.input-icon.material-icons-round {
    font-size: 22px;
}

.search-input {
    width: 100%;
    padding: 16px 16px 16px 52px;
    background-color: var(--md-sys-color-surface);
    border: 2px solid var(--md-sys-color-outline-variant);
    border-radius: var(--md-sys-corner-large);
    font-size: 16px;
    color: var(--md-sys-color-on-surface);
    transition: all var(--md-sys-motion-duration-short3) var(--md-sys-motion-easing-emphasized-decelerate);
    font-family: inherit;
}

.search-input::placeholder {
    color: var(--md-sys-color-on-surface-variant);
}

.search-input:hover {
    border-color: var(--md-sys-color-outline);
    background-color: var(--md-sys-color-surface-container-low);
    transform: translateY(-1px);
}

.search-input:focus {
    border-color: var(--md-sys-color-primary);
    background-color: var(--md-sys-color-primary-container);
    color: var(--md-sys-color-on-primary-container);
    transform: translateY(-2px);
    box-shadow: 0 0 0 4px rgba(103, 80, 164, 0.15);
}

.search-input:focus::placeholder {
    color: var(--md-sys-color-on-primary-container);
    opacity: 0.7;
}

.textarea-input {
    padding: 16px 16px 16px 52px;
    resize: vertical;
    min-height: 120px;
    line-height: 1.6;
}

/* ========== 按钮 ========== */
.primary-button {
    width: 100%;
    padding: 16px 32px;
    background-color: var(--md-sys-color-primary);
    color: var(--md-sys-color-on-primary);
    border: none;
    border-radius: var(--md-sys-corner-full);
    font-size: 16px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--md-sys-motion-duration-short3) var(--md-sys-motion-easing-emphasized-decelerate),
                box-shadow var(--md-sys-motion-duration-short2) var(--md-sys-motion-easing);
    box-shadow: var(--md-sys-elevation-1);
    font-family: inherit;
    min-height: 56px;
    position: relative;
    overflow: hidden;
}

.primary-button::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background-color: rgba(255, 255, 255, 0.3);
    transform: translate(-50%, -50%);
    transition: width var(--md-sys-motion-duration-medium1) var(--md-sys-motion-easing-emphasized-decelerate),
                height var(--md-sys-motion-duration-medium1) var(--md-sys-motion-easing-emphasized-decelerate);
}

.primary-button:hover::before {
    width: 300%;
    height: 300%;
}

.primary-button:hover:not(:disabled) {
    box-shadow: var(--md-sys-elevation-3);
    transform: translateY(-2px) scale(1.02);
}

.primary-button:active:not(:disabled) {
    transform: translateY(0) scale(0.96);
    box-shadow: var(--md-sys-elevation-1);
}

.primary-button:disabled {
    background-color: var(--md-sys-color-surface-container-high);
    color: var(--md-sys-color-on-surface-variant);
    box-shadow: none;
    cursor: not-allowed;
    animation: pulse var(--md-sys-motion-duration-long2) var(--md-sys-motion-easing) infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.6; }
}

.secondary-button {
    padding: 12px 24px;
    background-color: transparent;
    color: var(--md-sys-color-primary);
    border: 2px solid var(--md-sys-color-outline);
    border-radius: var(--md-sys-corner-full);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--md-sys-motion-duration-short3) var(--md-sys-motion-easing-emphasized-decelerate);
    font-family: inherit;
}

.secondary-button:hover:not(:disabled) {
    background-color: var(--md-sys-color-primary-container);
    border-color: var(--md-sys-color-primary);
    transform: translateY(-2px);
}

.secondary-button:active:not(:disabled) {
    transform: translateY(0) scale(0.98);
}

.secondary-button:disabled {
    color: var(--md-sys-color-on-surface-variant);
    border-color: var(--md-sys-color-outline-variant);
    cursor: not-allowed;
}

.button-group {
    display: flex;
    gap: 12px;
}

/* ========== 设置行 ========== */
.settings-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 16px;
}

.settings-label {
    font-size: 14px;
    font-weight: 500;
    color: var(--md-sys-color-on-surface);
}

.select-input {
    padding: 12px 16px;
    background-color: var(--md-sys-color-surface);
    border: 2px solid var(--md-sys-color-outline-variant);
    border-radius: var(--md-sys-corner-medium);
    font-size: 14px;
    color: var(--md-sys-color-on-surface);
    cursor: pointer;
    transition: all 0.3s var(--md-sys-motion-easing);
    font-family: inherit;
    min-width: 160px;
}

.select-input:hover {
    border-color: var(--md-sys-color-outline);
    background-color: var(--md-sys-color-surface-container-low);
}

.select-input:focus {
    border-color: var(--md-sys-color-primary);
    background-color: var(--md-sys-color-primary-container);
    color: var(--md-sys-color-on-primary-container);
}

/* ========== 结果卡片 ========== */
.results-container {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.result-card {
    background-color: var(--md-sys-color-surface);
    border-radius: var(--md-sys-corner-medium);
    padding: 16px;
    box-shadow: var(--md-sys-elevation-1);
    transition: all var(--md-sys-motion-duration-short4) var(--md-sys-motion-easing-emphasized-decelerate),
                box-shadow var(--md-sys-motion-duration-short3) var(--md-sys-motion-easing);
    animation: slideIn var(--md-sys-motion-duration-short4) var(--md-sys-motion-easing-emphasized-decelerate);
    position: relative;
}

.result-card:nth-child(1) { animation-delay: 0ms; }
.result-card:nth-child(2) { animation-delay: 50ms; }
.result-card:nth-child(3) { animation-delay: 100ms; }
.result-card:nth-child(4) { animation-delay: 150ms; }
.result-card:nth-child(5) { animation-delay: 200ms; }
.result-card:nth-child(n+6) { animation-delay: 250ms; }

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(16px) scale(0.98);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

.result-card:hover {
    box-shadow: var(--md-sys-elevation-3);
    background-color: var(--md-sys-color-surface-container-low);
    transform: translateY(-4px) scale(1.01);
}

.result-header {
    display: flex;
    align-items: center;
    gap: 16px;
    cursor: pointer;
    transition: all var(--md-sys-motion-duration-short2) var(--md-sys-motion-easing);
}

.result-header:active {
    transform: scale(0.99);
}

.result-cover {
    width: 64px;
    height: 64px;
    border-radius: var(--md-sys-corner-small);
    object-fit: cover;
    box-shadow: var(--md-sys-elevation-1);
    flex-shrink: 0;
    transition: transform var(--md-sys-motion-duration-short3) var(--md-sys-motion-easing-emphasized-decelerate);
}

.result-card:hover .result-cover {
    transform: scale(1.05) rotate(2deg);
}
}

.result-info {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.result-title {
    font-size: 16px;
    font-weight: 500;
    color: var(--md-sys-color-on-surface);
    margin-bottom: 4px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.result-artist {
    font-size: 14px;
    color: var(--md-sys-color-on-surface-variant);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.result-actions {
    display: flex;
    gap: 8px;
    flex-shrink: 0;
}

.action-btn {
    padding: 6px 14px;
    background-color: var(--md-sys-color-secondary-container);
    color: var(--md-sys-color-on-secondary-container);
    border: none;
    border-radius: var(--md-sys-corner-full);
    font-size: 12px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s var(--md-sys-motion-easing);
    font-family: inherit;
}

.action-btn:hover {
    background-color: var(--md-sys-color-secondary);
    color: var(--md-sys-color-on-secondary);
    transform: scale(1.05);
}

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

.action-hint {
    color: var(--md-sys-color-on-surface-variant);
    transition: transform 0.3s var(--md-sys-motion-easing);
    flex-shrink: 0;
    width: 24px;
    height: 24px;
}

.result-header {
    cursor: pointer;
}

/* ========== 音质面板 ========== */
.quality-panel {
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--md-sys-motion-duration-short4) var(--md-sys-motion-easing-emphasized-decelerate),
                opacity var(--md-sys-motion-duration-short2) var(--md-sys-motion-easing-emphasized-decelerate),
                margin-top var(--md-sys-motion-duration-short2) var(--md-sys-motion-easing-emphasized-decelerate),
                padding-top var(--md-sys-motion-duration-short2) var(--md-sys-motion-easing-emphasized-decelerate);
    margin-top: 0;
    opacity: 0;
    padding-top: 0;
    border-top: 1px solid transparent;
}

.quality-panel.open {
    max-height: 600px;
    opacity: 1;
    margin-top: 12px;
    padding-top: 12px;
    border-top-color: var(--md-sys-color-outline-variant);
}

.quality-controls {
    display: flex;
    gap: 8px;
    align-items: center;
    flex-wrap: wrap;
    padding-top: 12px;
    border-top: 1px solid var(--md-sys-color-outline-variant);
}

.quality-controls label {
    font-size: 13px;
    color: var(--md-sys-color-on-surface-variant);
    white-space: nowrap;
}

.quality-controls select {
    min-width: 140px;
}

/* ========== 歌单信息卡片 ========== */
.playlist-info-card {
    background: linear-gradient(135deg, var(--md-sys-color-primary), var(--md-sys-color-secondary));
    border-radius: var(--md-sys-corner-extra-large);
    padding: 24px;
    margin-bottom: 24px;
    color: var(--md-sys-color-on-primary);
    display: none;
    box-shadow: var(--md-sys-elevation-3);
    animation: slideIn var(--md-sys-motion-duration-medium1) var(--md-sys-motion-easing-emphasized-decelerate);
}

.playlist-info-card.show {
    display: block;
}

/* ========== 歌单歌曲展示区域 ========== */
.playlist-song-section {
    margin-top: 24px;
    animation: blurIn var(--md-sys-motion-duration-medium1) var(--md-sys-motion-easing-emphasized-decelerate);
}

.playlist-info-header {
    display: flex;
    gap: 20px;
    align-items: center;
}

.playlist-info-cover {
    width: 100px;
    height: 100px;
    border-radius: var(--md-sys-corner-large);
    box-shadow: var(--md-sys-elevation-2);
    transition: transform var(--md-sys-motion-duration-short4) var(--md-sys-motion-easing-emphasized-decelerate);
}

.playlist-info-header:hover .playlist-info-cover {
    transform: scale(1.05) rotate(2deg);
}

.playlist-info-details h3 {
    font-size: 24px;
    font-weight: 500;
    margin-bottom: 8px;
}

.playlist-info-details p {
    font-size: 14px;
    opacity: 0.9;
}

/* ========== 用户信息卡片 ========== */
.user-info-card {
    background-color: var(--md-sys-color-surface-container);
    border-radius: var(--md-sys-corner-extra-large);
    padding: 24px;
    margin-bottom: 24px;
    display: flex;
    align-items: center;
    gap: 20px;
    box-shadow: var(--md-sys-elevation-1);
    animation: slideIn 0.4s var(--md-sys-motion-easing);
}

.user-avatar {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    object-fit: cover;
    box-shadow: var(--md-sys-elevation-2);
}

.user-details h3 {
    font-size: 20px;
    font-weight: 500;
    color: var(--md-sys-color-on-surface);
    margin-bottom: 8px;
}

.user-details p {
    font-size: 14px;
    color: var(--md-sys-color-on-surface-variant);
}

/* ========== 歌单网格 ========== */
.playlists-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 16px;
    margin-top: 24px;
}

.playlist-grid-card {
    background-color: var(--md-sys-color-surface);
    border-radius: var(--md-sys-corner-large);
    padding: 16px;
    cursor: pointer;
    transition: all 0.3s var(--md-sys-motion-easing);
    box-shadow: var(--md-sys-elevation-1);
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.playlist-grid-card:hover {
    box-shadow: var(--md-sys-elevation-3);
    transform: translateY(-8px) scale(1.02);
}

.playlist-grid-cover {
    width: 120px;
    height: 120px;
    border-radius: var(--md-sys-corner-medium);
    object-fit: cover;
    margin-bottom: 12px;
    box-shadow: var(--md-sys-elevation-1);
}

.playlist-grid-title {
    font-size: 15px;
    font-weight: 500;
    color: var(--md-sys-color-on-surface);
    margin-bottom: 4px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    width: 100%;
}

.playlist-grid-count {
    font-size: 13px;
    color: var(--md-sys-color-on-surface-variant);
}

/* ========== 分页 ========== */
.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 16px;
    margin: 24px 0;
}

.pagination-button {
    padding: 10px 20px;
    background-color: var(--md-sys-color-surface-container);
    color: var(--md-sys-color-on-surface);
    border: none;
    border-radius: var(--md-sys-corner-full);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s var(--md-sys-motion-easing);
    font-family: inherit;
}

.pagination-button:hover:not(:disabled) {
    background-color: var(--md-sys-color-primary);
    color: var(--md-sys-color-on-primary);
    transform: translateY(-2px);
    box-shadow: var(--md-sys-elevation-1);
}

.pagination-button:active:not(:disabled) {
    transform: translateY(0);
}

.pagination-button:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.pagination span {
    font-weight: 500;
    color: var(--md-sys-color-on-surface-variant);
    font-size: 14px;
}

/* ========== 加载动画 ========== */
.loader-container {
    display: none;
    justify-content: center;
    align-items: center;
    padding: 40px 0;
}

.spinner {
    width: 48px;
    height: 48px;
    border: 4px solid var(--md-sys-color-surface-container-high);
    border-top-color: var(--md-sys-color-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

/* ========== 错误卡片 ========== */
.error-card {
    background-color: var(--md-sys-color-error-container);
    color: var(--md-sys-color-on-error-container);
    border-radius: var(--md-sys-corner-large);
    padding: 16px;
    margin-bottom: 16px;
    animation: slideIn 0.4s var(--md-sys-motion-easing);
}

/* ========== 底部导航栏 ========== */
.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background-color: var(--md-sys-color-surface);
    box-shadow: 0 -2px 12px rgba(0,0,0,0.08);
    backdrop-filter: blur(8px);
    display: flex;
    justify-content: space-around;
    padding: 6px 0 14px 0;
    z-index: 1000;
}

.nav-item {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2px;
    padding: 8px 6px;
    background: none;
    border: none;
    cursor: pointer;
    transition: all var(--md-sys-motion-duration-short3) var(--md-sys-motion-easing-emphasized-decelerate);
    border-radius: var(--md-sys-corner-full);
    margin: 0 6px;
    position: relative;
    overflow: hidden;
}

.nav-item::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background-color: var(--md-sys-color-primary);
    opacity: 0.15;
    transform: translate(-50%, -50%);
    transition: width var(--md-sys-motion-duration-medium1) var(--md-sys-motion-easing-emphasized-decelerate),
                height var(--md-sys-motion-duration-medium1) var(--md-sys-motion-easing-emphasized-decelerate);
}

.nav-item:hover::before {
    width: 150%;
    height: 150%;
}

.nav-item:hover {
    background-color: var(--md-sys-color-surface-container);
    transform: translateY(-2px);
}

.nav-item:active {
    transform: translateY(0) scale(0.95);
}

.nav-item.active {
    background-color: var(--md-sys-color-primary-container);
    animation: elasticScale var(--md-sys-motion-duration-medium1) var(--md-sys-motion-easing-emphasized-decelerate);
}

.nav-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform var(--md-sys-motion-duration-short4) var(--md-sys-motion-easing-emphasized-decelerate);
}

.nav-icon.material-icons-round {
    font-size: 22px;
}

.nav-item.active .nav-icon {
    transform: scale(1.15) translateY(-2px);
    animation: bounce 1s var(--md-sys-motion-easing-emphasized-decelerate);
}

.nav-label {
    font-size: 12px;
    font-weight: 500;
    color: var(--md-sys-color-on-surface-variant);
    transition: all var(--md-sys-motion-duration-short3) var(--md-sys-motion-easing-emphasized-decelerate);
}

.nav-item.active .nav-label {
    color: var(--md-sys-color-on-primary-container);
    transform: translateY(-1px);
}

/* ========== Ripple 效果 ========== */
.ripple {
    position: absolute;
    border-radius: 50%;
    background-color: rgba(255, 255, 255, 0.6);
    width: 100px;
    height: 100px;
    margin-top: -50px;
    margin-left: -50px;
    animation: rippleEffect var(--md-sys-motion-duration-medium1) var(--md-sys-motion-easing-emphasized-decelerate);
    opacity: 0;
    pointer-events: none;
}

@keyframes rippleEffect {
    from {
        opacity: 0.8;
        transform: scale(0);
    }
    to {
        opacity: 0;
        transform: scale(4);
    }
}

/* ========== 响应式设计 ========== */
@media (max-width: 768px) {
    .app-bar-content {
        padding: 12px 16px;
    }

    .app-title {
        font-size: 20px;
    }

    .main-content {
        padding: 16px;
        padding-bottom: 80px;
    }

    .page-header h2 {
        font-size: 24px;
    }

    .card-header,
    .card-content {
        padding: 16px;
    }

    .result-header {
        gap: 8px;
    }

    .result-cover {
        width: 40px;
        height: 40px;
    }

    .result-title {
        font-size: 14px;
    }

    .result-artist {
        font-size: 12px;
    }

    .result-actions {
        gap: 6px;
    }

    .action-btn {
        padding: 6px 12px;
        font-size: 12px;
    }

    .playlist-info-header {
        flex-direction: column;
        text-align: center;
    }

    .playlists-grid {
        grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    }

    .button-group {
        flex-direction: column;
    }

    .quality-controls {
        flex-direction: column;
        align-items: stretch;
    }

    .download-progress-info {
        font-size: 12px;
        gap: 4px;
    }

    .download-progress-text {
        min-width: 50px;
    }
}

@media (max-width: 480px) {
    .nav-label {
        font-size: 10px;
    }

    .nav-icon.material-icons-round {
        font-size: 20px;
    }

    .nav-item {
        padding: 6px 4px;
        gap: 2px;
    }

    .playlists-grid {
        grid-template-columns: 1fr;
    }
}

/* ========== 滚动条样式 ========== */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--md-sys-color-surface-container);
}

::-webkit-scrollbar-thumb {
    background: var(--md-sys-color-on-surface-variant);
    border-radius: 4px;
    opacity: 0.3;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--md-sys-color-on-surface);
    opacity: 0.5;
}

/* ========== 下载进度条样式 ========== */
.download-progress-container {
    margin-top: 16px;
    padding: 20px;
    background-color: var(--md-sys-color-surface-container-low);
    border-radius: var(--md-sys-corner-large);
    animation: fadeIn 0.3s var(--md-sys-motion-easing);
}

.download-progress-bar {
    width: 100%;
    height: 16px;
    background-color: var(--md-sys-color-surface-container);
    border-radius: 8px;
    overflow: hidden;
    margin-bottom: 16px;
}

.download-progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--md-sys-color-primary), var(--md-sys-color-secondary));
    border-radius: 8px;
    transition: width 0.2s var(--md-sys-motion-easing);
    width: 0%;
}

.download-progress-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 13px;
    color: var(--md-sys-color-on-surface-variant);
    gap: 8px;
    flex-wrap: wrap;
}

.download-progress-text {
    flex: 0 0 auto;
    min-width: 60px;
}

.download-speed-text,
.download-time-text {
    flex: 1;
    min-width: 0;
    text-align: right;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
    text-align: center;
}

.download-progress-text {
    font-weight: 500;
    color: var(--md-sys-color-primary);
}

/* ========== 歌词相关样式 ========== */
.lyrics-output-wrapper {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.lyrics-textarea {
    width: 100%;
    min-height: 400px;
    padding: 16px;
    background-color: var(--md-sys-color-surface-container-low);
    border: 2px solid var(--md-sys-color-outline-variant);
    border-radius: var(--md-sys-corner-large);
    font-family: 'Fira Code', 'Consolas', 'Monaco', monospace;
    font-size: 14px;
    line-height: 1.6;
    color: var(--md-sys-color-on-surface);
    resize: vertical;
    transition: all var(--md-sys-motion-duration-short3) var(--md-sys-motion-easing-emphasized-decelerate);
}

.lyrics-textarea:focus {
    border-color: var(--md-sys-color-primary);
    background-color: var(--md-sys-color-primary-container);
    color: var(--md-sys-color-on-primary-container);
    box-shadow: 0 0 0 4px rgba(103, 80, 164, 0.15);
    transform: translateY(-2px);
}

.lyrics-textarea::placeholder {
    color: var(--md-sys-color-on-surface-variant);
}

.lyrics-result-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px;
    background-color: var(--md-sys-color-success-container);
    color: var(--md-sys-color-on-success-container);
    border-radius: var(--md-sys-corner-large);
    margin-top: 16px;
    animation: fadeIn var(--md-sys-motion-duration-short4) var(--md-sys-motion-easing-emphasized-decelerate);
}

.lyrics-result-info strong {
    font-weight: 600;
}