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

:root {
    --bg-primary: #121212;
    --bg-secondary: #181818;
    --bg-tertiary: #282828;
    --bg-hover: #2a2a2a;
    --text-primary: #ffffff;
    --text-secondary: #b3b3b3;
    --accent-primary: #1db954;
    --accent-hover: #1ed760;
    --border-color: #282828;
    --cassette-color: #ff6b6b;
    --cassette-window: #2d2d2d;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    overflow: hidden;
}

.app-container {
    display: flex;
    height: calc(var(--vh, 1vh) * 100 - 90px);
}

/* Sidebar */
.sidebar {
    width: 280px;
    background-color: var(--bg-primary);
    padding: 24px;
    display: flex;
    flex-direction: column;
    border-right: 1px solid var(--border-color);
    overflow-y: auto;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 32px;
    color: var(--text-primary);
}

.logo svg {
    color: var(--accent-primary);
}

.logo h1 {
    font-size: 24px;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.nav-menu {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-bottom: 32px;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 12px 16px;
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    border-radius: 8px;
    transition: all 0.2s;
}

.nav-item:hover {
    color: var(--text-primary);
    background-color: var(--bg-tertiary);
}

.nav-item.active {
    color: var(--text-primary);
    background-color: var(--bg-tertiary);
}

.playlist-section {
    flex: 1;
    overflow-y: auto;
}

.playlist-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
}

.playlist-header h3 {
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
    color: var(--text-secondary);
    letter-spacing: 1px;
    margin: 0;
}

.playlist-header .btn-icon {
    padding: 4px;
}

.playlist-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.playlist-item {
    padding: 8px 12px;
    color: var(--text-secondary);
    font-size: 14px;
    cursor: pointer;
    border-radius: 4px;
    transition: all 0.2s;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative;
}

.playlist-item:hover {
    color: var(--text-primary);
    background-color: var(--bg-tertiary);
}

.playlist-item.active {
    color: var(--accent-primary);
    background-color: var(--bg-tertiary);
}

.playlist-item-info {
    flex: 1;
    min-width: 0;
}

.playlist-item-name {
    font-weight: 500;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.playlist-item-count {
    font-size: 11px;
    color: var(--text-secondary);
    margin-top: 2px;
}

.playlist-item-actions {
    display: none;
    gap: 4px;
}

.playlist-item:hover .playlist-item-actions {
    display: flex;
}

.playlist-item-actions .btn-icon {
    padding: 4px;
    opacity: 0.7;
}

.playlist-item-actions .btn-icon:hover {
    opacity: 1;
}

/* Main Content */
.main-content {
    flex: 1;
    background: linear-gradient(180deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
    overflow-y: auto;
    padding: 24px;
}

.content-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 32px;
    gap: 16px;
    flex-wrap: wrap;
}

.search-bar {
    display: flex;
    align-items: center;
    gap: 12px;
    background-color: var(--bg-tertiary);
    padding: 12px 16px;
    border-radius: 24px;
    flex: 1;
    max-width: 400px;
}

.search-bar svg {
    color: var(--text-secondary);
}

.search-bar input {
    flex: 1;
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 14px;
    outline: none;
}

.search-bar input::placeholder {
    color: var(--text-secondary);
}

.api-key-section {
    display: flex;
    gap: 8px;
}

#apiKeyInput {
    padding: 10px 16px;
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    color: var(--text-primary);
    font-size: 14px;
    outline: none;
    width: 250px;
}

.btn-primary {
    padding: 10px 24px;
    background-color: var(--accent-primary);
    color: var(--text-primary);
    border: none;
    border-radius: 20px;
    font-weight: 600;
    font-size: 14px;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-primary:hover {
    background-color: var(--accent-hover);
    transform: scale(1.04);
}

.btn-secondary {
    padding: 10px 24px;
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    font-weight: 600;
    font-size: 14px;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-secondary:hover {
    background-color: var(--bg-hover);
    transform: scale(1.04);
}

.view {
    display: none;
}

.view.active {
    display: block;
}

.section-title {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 20px;
    margin-top: 32px;
}

.section-title:first-child {
    margin-top: 0;
}

.music-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 20px;
    margin-bottom: 32px;
}

.music-card {
    background-color: var(--bg-secondary);
    padding: 16px;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s;
    position: relative;
}

.music-card:hover {
    background-color: var(--bg-tertiary);
    transform: translateY(-4px);
}

.music-card-image {
    width: 100%;
    aspect-ratio: 1;
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 12px;
    position: relative;
}

.music-card-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.play-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity 0.3s;
}

.music-card:hover .play-overlay {
    opacity: 1;
}

.play-overlay svg {
    width: 48px;
    height: 48px;
    color: var(--text-primary);
    filter: drop-shadow(0 2px 8px rgba(0, 0, 0, 0.3));
}

.music-card-title {
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 4px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.music-card-artist {
    font-size: 12px;
    color: var(--text-secondary);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* Player Bar */
.player-bar {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    height: 90px;
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 16px;
    padding-bottom: max(0px, env(safe-area-inset-bottom));
    gap: 16px;
    z-index: 100;
}

.player-track-info {
    display: flex;
    align-items: center;
    gap: 12px;
    min-width: 280px;
    flex: 1;
}

.track-thumbnail {
    width: 56px;
    height: 56px;
    border-radius: 4px;
    overflow: hidden;
    background-color: var(--bg-tertiary);
}

.track-thumbnail img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.track-details {
    flex: 1;
    min-width: 0;
}

.track-title {
    font-size: 14px;
    font-weight: 600;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.track-artist {
    font-size: 12px;
    color: var(--text-secondary);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.player-controls {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    flex: 2;
    max-width: 700px;
}

.control-buttons {
    display: flex;
    align-items: center;
    gap: 16px;
}

.btn-icon {
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 8px;
    border-radius: 50%;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
}

.btn-icon:hover {
    color: var(--text-primary);
    background-color: var(--bg-hover);
}

.btn-icon.active {
    color: var(--accent-primary);
}

.btn-play {
    width: 40px;
    height: 40px;
    background-color: var(--text-primary);
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
}

.btn-play:hover {
    transform: scale(1.06);
}

.btn-play svg {
    color: var(--bg-primary);
}

.progress-bar {
    display: flex;
    align-items: center;
    gap: 12px;
    width: 100%;
}

.time {
    font-size: 12px;
    color: var(--text-secondary);
    min-width: 40px;
}

.progress-track {
    flex: 1;
    height: 4px;
    background-color: var(--bg-tertiary);
    border-radius: 2px;
    position: relative;
    cursor: pointer;
}

.progress-fill {
    height: 100%;
    background-color: var(--text-primary);
    border-radius: 2px;
    width: 0%;
    transition: width 0.1s linear;
    pointer-events: none;
}

.progress-slider {
    position: absolute;
    top: 50%;
    left: 0;
    transform: translateY(-50%);
    width: 100%;
    height: 4px;
    opacity: 0;
    cursor: pointer;
    appearance: none;
    -webkit-appearance: none;
}

.progress-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--text-primary);
    cursor: pointer;
}

.progress-track:hover .progress-fill {
    background-color: var(--accent-primary);
}

.player-extras {
    display: flex;
    align-items: center;
    gap: 8px;
    min-width: 280px;
    flex: 1;
    justify-content: flex-end;
}

.volume-control {
    display: flex;
    align-items: center;
    gap: 8px;
}

.volume-slider {
    width: 100px;
    height: 4px;
    background-color: var(--bg-tertiary);
    border-radius: 2px;
    outline: none;
    appearance: none;
    -webkit-appearance: none;
}

.volume-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--text-primary);
    cursor: pointer;
}

.volume-slider::-moz-range-thumb {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--text-primary);
    cursor: pointer;
    border: none;
}

/* Cassette Modal */
.cassette-modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.9);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    backdrop-filter: blur(10px);
}

.cassette-modal.active {
    display: flex;
}

.cassette-container {
    position: relative;
    padding: 40px;
}

.close-button {
    position: absolute;
    top: 10px;
    right: 10px;
    background: rgba(255, 255, 255, 0.1);
    border: none;
    color: var(--text-primary);
    cursor: pointer;
    padding: 8px;
    border-radius: 50%;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
}

.close-button:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: rotate(90deg);
}

.cassette-tape {
    width: 500px;
    height: 320px;
    perspective: 1000px;
}

.cassette-body {
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #ff6b6b 0%, #ee5a6f 100%);
    border-radius: 12px;
    padding: 20px;
    box-shadow: 
        0 10px 40px rgba(0, 0, 0, 0.5),
        inset 0 2px 4px rgba(255, 255, 255, 0.2),
        inset 0 -2px 4px rgba(0, 0, 0, 0.2);
    position: relative;
}

.cassette-label {
    background: rgba(255, 255, 255, 0.9);
    border-radius: 4px;
    padding: 12px;
    margin-bottom: 16px;
    text-align: center;
}

.label-text {
    font-size: 10px;
    font-weight: 700;
    color: #333;
    letter-spacing: 2px;
    margin-bottom: 4px;
}

.label-title {
    font-size: 14px;
    font-weight: 600;
    color: #111;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.cassette-window {
    background: rgba(0, 0, 0, 0.3);
    border-radius: 8px;
    padding: 20px;
    display: flex;
    justify-content: space-around;
    align-items: center;
    margin-bottom: 16px;
    box-shadow: inset 0 2px 8px rgba(0, 0, 0, 0.5);
}

.reel {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    background: radial-gradient(circle, #1a1a1a 0%, #0a0a0a 100%);
    position: relative;
    box-shadow: 
        0 2px 8px rgba(0, 0, 0, 0.5),
        inset 0 2px 4px rgba(255, 255, 255, 0.1);
}

.reel.playing {
    animation: spin 2s linear infinite;
}

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

.reel-center {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 30px;
    height: 30px;
    background: #333;
    border-radius: 50%;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.5);
}

.reel-center::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 8px;
    height: 8px;
    background: #666;
    border-radius: 50%;
}

.reel-teeth {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
}

.reel-teeth::before,
.reel-teeth::after {
    content: '';
    position: absolute;
    width: 2px;
    height: 40px;
    background: #444;
    left: 50%;
    top: 50%;
    transform-origin: center;
}

.reel-teeth::before {
    transform: translate(-50%, -50%) rotate(45deg);
}

.reel-teeth::after {
    transform: translate(-50%, -50%) rotate(-45deg);
}

.cassette-holes {
    display: flex;
    justify-content: space-around;
    padding: 0 40px;
}

.hole {
    width: 20px;
    height: 20px;
    background: rgba(0, 0, 0, 0.4);
    border-radius: 4px;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.5);
}

/* Loading State */
.loading {
    text-align: center;
    padding: 40px;
    color: var(--text-secondary);
}

.loading::after {
    content: '...';
    animation: dots 1.5s steps(4, end) infinite;
}

@keyframes dots {
    0%, 20% {
        content: '.';
    }
    40% {
        content: '..';
    }
    60%, 100% {
        content: '...';
    }
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 12px;
}

::-webkit-scrollbar-track {
    background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
    background: var(--bg-tertiary);
    border-radius: 6px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--bg-hover);
}

/* Playlist Modal */
.playlist-modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.9);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    backdrop-filter: blur(10px);
}

.playlist-modal.active {
    display: flex;
}

.playlist-modal-content {
    background: var(--bg-secondary);
    border-radius: 12px;
    width: 90%;
    max-width: 500px;
    max-height: 80vh;
    overflow-y: auto;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
}

.playlist-modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 24px;
    border-bottom: 1px solid var(--border-color);
}

.playlist-modal-header h2 {
    font-size: 24px;
    font-weight: 700;
}

.playlist-modal-body {
    padding: 24px;
}

.playlist-input {
    width: 100%;
    padding: 12px 16px;
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 14px;
    outline: none;
    margin-bottom: 16px;
    font-family: inherit;
}

.playlist-input:focus {
    border-color: var(--accent-primary);
}

.playlist-textarea {
    width: 100%;
    padding: 12px 16px;
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 14px;
    outline: none;
    margin-bottom: 16px;
    font-family: inherit;
    resize: vertical;
    min-height: 80px;
}

.playlist-textarea:focus {
    border-color: var(--accent-primary);
}

.playlist-modal-actions {
    display: flex;
    gap: 12px;
    justify-content: flex-end;
}

.playlist-modal-actions .btn-primary,
.playlist-modal-actions .btn-secondary {
    flex: 1;
}

.playlist-selection-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
    max-height: 300px;
    overflow-y: auto;
}

.playlist-selection-item {
    padding: 12px 16px;
    background-color: var(--bg-tertiary);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.playlist-selection-item:hover {
    background-color: var(--bg-hover);
    transform: translateX(4px);
}

.playlist-selection-item-info {
    flex: 1;
}

.playlist-selection-item-name {
    font-weight: 500;
    margin-bottom: 4px;
}

.playlist-selection-item-count {
    font-size: 12px;
    color: var(--text-secondary);
}

.playlist-selection-item svg {
    color: var(--accent-primary);
}

/* Music Card Context Menu */
.music-card {
    position: relative;
}

.music-card-menu {
    position: absolute;
    top: 8px;
    right: 8px;
    opacity: 0;
    transition: opacity 0.2s;
    z-index: 10;
}

.music-card:hover .music-card-menu {
    opacity: 1;
}

.music-card-menu-btn {
    background: rgba(0, 0, 0, 0.7);
    border: none;
    color: var(--text-primary);
    padding: 8px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
    backdrop-filter: blur(4px);
}

.music-card-menu-btn:hover {
    background: rgba(0, 0, 0, 0.9);
    transform: scale(1.1);
}

.music-card-menu-btn.remove-btn {
    background: rgba(255, 68, 68, 0.7);
}

.music-card-menu-btn.remove-btn:hover {
    background: rgba(255, 68, 68, 0.9);
}

/* Always show menu buttons on mobile/touch devices */
@media (hover: none) and (pointer: coarse) {
    .music-card-menu {
        opacity: 1;
    }

    .music-card-menu-btn {
        background: rgba(0, 0, 0, 0.8);
        box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
    }

    .music-card-menu-btn.remove-btn {
        background: rgba(255, 68, 68, 0.85);
    }

    .music-card-menu-btn:active {
        transform: scale(0.9);
    }
}

/* API Key Management Modal */
.api-modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.9);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    backdrop-filter: blur(10px);
}

.api-modal.active {
    display: flex;
}

.api-modal-content {
    background: var(--bg-secondary);
    border-radius: 12px;
    width: 90%;
    max-width: 600px;
    max-height: 80vh;
    overflow-y: auto;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
}

.api-modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 24px;
    border-bottom: 1px solid var(--border-color);
}

.api-modal-header h2 {
    font-size: 24px;
    font-weight: 700;
}

.api-modal-body {
    padding: 24px;
}

.api-keys-list {
    margin-bottom: 32px;
}

.api-key-item {
    background: var(--bg-tertiary);
    padding: 16px;
    border-radius: 8px;
    margin-bottom: 12px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.api-key-info {
    flex: 1;
    min-width: 0;
}

.api-key-value {
    font-family: monospace;
    font-size: 12px;
    color: var(--text-secondary);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    margin-bottom: 8px;
}

.api-key-usage {
    font-size: 12px;
    color: var(--text-secondary);
}

.api-key-usage-bar {
    height: 4px;
    background: var(--bg-hover);
    border-radius: 2px;
    margin-top: 8px;
    overflow: hidden;
}

.api-key-usage-fill {
    height: 100%;
    background: var(--accent-primary);
    transition: width 0.3s;
}

.api-key-usage-fill.warning {
    background: #ffa500;
}

.api-key-usage-fill.danger {
    background: #ff4444;
}

.api-key-actions {
    display: flex;
    gap: 8px;
}

.btn-icon-small {
    background: var(--bg-hover);
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 8px;
    border-radius: 4px;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
}

.btn-icon-small:hover {
    color: var(--text-primary);
    background-color: var(--bg-tertiary);
}

.btn-icon-small.delete:hover {
    color: #ff4444;
}

.api-stats {
    background: var(--bg-tertiary);
    padding: 16px;
    border-radius: 8px;
}

.api-stats h3 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 16px;
}

.stat-item {
    display: flex;
    justify-content: space-between;
    padding: 8px 0;
    border-bottom: 1px solid var(--bg-hover);
}

.stat-item:last-child {
    border-bottom: none;
}

.stat-label {
    color: var(--text-secondary);
    font-size: 14px;
}

.stat-value {
    color: var(--text-primary);
    font-weight: 600;
    font-size: 14px;
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
    display: none;
    position: fixed;
    top: 16px;
    left: 16px;
    z-index: 1001;
    background: var(--bg-secondary);
    border: none;
    color: var(--text-primary);
    padding: 12px;
    border-radius: 8px;
    cursor: pointer;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
    transition: all 0.3s;
}

.mobile-menu-toggle:hover {
    background: var(--bg-tertiary);
    transform: scale(1.05);
}

.mobile-menu-toggle:active {
    transform: scale(0.95);
}

/* Sidebar Overlay */
.sidebar-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.7);
    z-index: 999;
    opacity: 0;
    transition: opacity 0.3s;
    backdrop-filter: blur(4px);
}

.sidebar-overlay.active {
    display: block;
    opacity: 1;
}

/* Prevent body scroll when menu is open */
body.menu-open {
    overflow: hidden;
}

/* Responsive Breakpoints */

/* Tablets and below (768px) */
@media (max-width: 768px) {
    .mobile-menu-toggle {
        display: flex;
        align-items: center;
        justify-content: center;
    }

    .sidebar {
        position: fixed;
        left: -280px;
        top: 0;
        bottom: 0;
        width: 280px;
        z-index: 1000;
        transition: left 0.3s ease-in-out;
        box-shadow: 2px 0 12px rgba(0, 0, 0, 0.5);
    }

    .sidebar.mobile-active {
        left: 0;
    }

    .app-container {
        height: calc(var(--vh, 1vh) * 100 - 140px);
    }

    .main-content {
        padding: 16px;
        padding-top: 60px;
    }

    .content-header {
        flex-direction: column;
        align-items: stretch;
        gap: 12px;
    }

    .search-bar {
        max-width: 100%;
        width: 100%;
    }

    .api-key-section {
        flex-direction: column;
        width: 100%;
        gap: 8px;
    }

    #apiKeyInput {
        width: 100%;
    }

    .btn-primary,
    .btn-secondary {
        width: 100%;
        padding: 12px 24px;
    }

    .section-title {
        font-size: 20px;
        margin-top: 24px;
    }

    .music-grid {
        grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
        gap: 12px;
    }

    /* Player Bar Mobile */
    .player-bar {
        height: auto;
        min-height: 140px;
        padding: 12px;
        padding-bottom: max(12px, env(safe-area-inset-bottom));
        flex-direction: column;
        gap: 12px;
    }

    .player-track-info {
        width: 100%;
        min-width: auto;
        justify-content: flex-start;
    }

    .player-controls {
        width: 100%;
        max-width: 100%;
        order: 3;
    }

    .control-buttons {
        gap: 12px;
    }

    .btn-play {
        width: 48px;
        height: 48px;
    }

    .progress-bar {
        width: 100%;
    }

    .player-extras {
        width: 100%;
        min-width: auto;
        justify-content: space-between;
        order: 2;
    }

    .volume-control {
        flex: 1;
        max-width: 200px;
    }

    .volume-slider {
        flex: 1;
        width: auto;
    }

    /* Cassette Modal Mobile */
    .cassette-tape {
        width: 90vw;
        max-width: 400px;
        height: auto;
        aspect-ratio: 1.5625;
    }

    .cassette-body {
        padding: 16px;
    }

    .cassette-window {
        padding: 16px;
        margin-bottom: 12px;
    }

    .reel {
        width: 70px;
        height: 70px;
    }

    .reel-center {
        width: 24px;
        height: 24px;
    }

    .label-title {
        font-size: 12px;
    }

    /* API Modal Mobile */
    .api-modal-content {
        width: 95%;
        max-height: 90vh;
    }

    .api-modal-header {
        padding: 16px;
    }

    .api-modal-header h2 {
        font-size: 20px;
    }

    .api-modal-body {
        padding: 16px;
    }

    .api-key-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }

    .api-key-actions {
        width: 100%;
        justify-content: flex-end;
    }
}

/* Small Mobile Devices (480px and below) */
@media (max-width: 480px) {
    .logo h1 {
        font-size: 20px;
    }

    /* Ensure content area accounts for taller mobile player bar */
    .app-container {
        height: calc(var(--vh, 1vh) * 100 - 160px);
    }

    .music-grid {
        grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
        gap: 10px;
    }

    .music-card {
        padding: 12px;
    }

    .music-card-title {
        font-size: 13px;
    }

    .music-card-artist {
        font-size: 11px;
    }

    .section-title {
        font-size: 18px;
        margin-top: 20px;
    }

    .player-bar {
        min-height: 160px;
        padding: 10px;
        padding-bottom: max(10px, env(safe-area-inset-bottom));
    }

    .track-thumbnail {
        width: 48px;
        height: 48px;
    }

    .track-title {
        font-size: 13px;
    }

    .track-artist {
        font-size: 11px;
    }

    .btn-play {
        width: 44px;
        height: 44px;
    }

    .btn-icon {
        padding: 6px;
    }

    .control-buttons {
        gap: 8px;
    }

    .control-buttons svg {
        width: 18px;
        height: 18px;
    }

    .time {
        font-size: 11px;
        min-width: 35px;
    }

    .cassette-tape {
        width: 95vw;
    }

    .cassette-body {
        padding: 12px;
    }

    .reel {
        width: 60px;
        height: 60px;
    }

    .reel-center {
        width: 20px;
        height: 20px;
    }

    .reel-center::before {
        width: 6px;
        height: 6px;
    }
}

/* Landscape Mobile Devices */
@media (max-width: 768px) and (orientation: landscape) {
    .app-container {
        height: calc(100vh - 100px);
    }

    .player-bar {
        min-height: 100px;
        padding-bottom: max(16px, env(safe-area-inset-bottom));
        flex-direction: row;
        flex-wrap: wrap;
    }

    .player-track-info {
        flex: 1;
        min-width: 200px;
    }

    .player-controls {
        flex: 2;
        min-width: 300px;
    }

    .player-extras {
        flex: 1;
        min-width: 150px;
    }
}

/* Large Tablets (between 769px and 1024px) */
@media (min-width: 769px) and (max-width: 1024px) {
    .sidebar {
        width: 240px;
    }

    .music-grid {
        grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
        gap: 16px;
    }

    .main-content {
        padding: 20px;
    }
}

/* Touch-friendly enhancements for all mobile devices */
@media (hover: none) and (pointer: coarse) {
    .btn-icon,
    .btn-play,
    .nav-item,
    .music-card,
    .playlist-item {
        -webkit-tap-highlight-color: transparent;
    }

    .btn-icon:active,
    .btn-play:active {
        transform: scale(0.9);
    }

    .music-card:active {
        transform: scale(0.98);
    }

    /* Larger touch targets */
    .btn-icon {
        min-width: 44px;
        min-height: 44px;
    }

    .nav-item {
        padding: 14px 16px;
    }

    /* Smooth scrolling */
    .main-content,
    .sidebar {
        -webkit-overflow-scrolling: touch;
    }
}

/* Local Files Upload Section */
.local-upload-section {
    margin-bottom: 32px;
}

.upload-area {
    border: 2px dashed var(--border-color);
    border-radius: 12px;
    padding: 48px 24px;
    text-align: center;
    background: var(--bg-secondary);
    transition: all 0.3s;
    cursor: pointer;
}

.upload-area:hover {
    border-color: var(--accent-primary);
    background: var(--bg-tertiary);
}

.upload-area.drag-over {
    border-color: var(--accent-primary);
    background: var(--bg-tertiary);
    transform: scale(1.02);
}

.upload-area svg {
    color: var(--text-secondary);
    margin-bottom: 16px;
}

.upload-area h3 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 8px;
}

.upload-area p {
    color: var(--text-secondary);
    font-size: 14px;
}

/* High DPI Displays */
@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
    .music-card-image img {
        image-rendering: -webkit-optimize-contrast;
    }
}

/* ============================================
   CUSTOM NOTIFICATIONS & DIALOGS
   ============================================ */

.custom-notification {
    position: fixed;
    top: 20px;
    right: 20px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    padding: 16px 20px;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.5);
    z-index: 10000;
    display: flex;
    align-items: center;
    gap: 12px;
    min-width: 280px;
    max-width: 400px;
    animation: slideIn 0.3s ease-out;
    border-left: 4px solid var(--accent-primary);
}

.custom-notification.success {
    border-left-color: var(--accent-primary);
}

.custom-notification.error {
    border-left-color: #ff4444;
}

.custom-notification.warning {
    border-left-color: #ffa500;
}

.custom-notification.info {
    border-left-color: #4a9eff;
}

.notification-icon {
    font-size: 20px;
    font-weight: bold;
    flex-shrink: 0;
}

.notification-message {
    flex: 1;
    font-size: 14px;
    line-height: 1.4;
}

.notification-close {
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 24px;
    cursor: pointer;
    padding: 0;
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
    transition: all 0.2s;
    flex-shrink: 0;
}

.notification-close:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

.custom-notification.fade-out {
    animation: slideOut 0.3s ease-out forwards;
}

@keyframes slideIn {
    from {
        transform: translateX(400px);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

@keyframes slideOut {
    from {
        transform: translateX(0);
        opacity: 1;
    }
    to {
        transform: translateX(400px);
        opacity: 0;
    }
}

/* Custom Confirm Dialog */
.custom-confirm-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10001;
    animation: fadeIn 0.2s ease-out;
}

.custom-confirm-dialog {
    background: var(--bg-secondary);
    border-radius: 12px;
    padding: 24px;
    max-width: 400px;
    width: 90%;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
    animation: scaleIn 0.3s ease-out;
}

.confirm-message {
    font-size: 16px;
    line-height: 1.5;
    margin-bottom: 24px;
    color: var(--text-primary);
}

.confirm-actions {
    display: flex;
    gap: 12px;
    justify-content: flex-end;
}

.confirm-actions button {
    flex: 1;
    max-width: 120px;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes scaleIn {
    from {
        transform: scale(0.9);
        opacity: 0;
    }
    to {
        transform: scale(1);
        opacity: 1;
    }
}

/* ============================================
   MOBILE VIEWPORT HEIGHT FIX
   ============================================ */

:root {
    --vh: 1vh;
}

/* ============================================
   BROWSER COMPATIBILITY FIXES
   ============================================ */

/* Backdrop filter fallback */
.no-backdrop-filter .cassette-modal,
.no-backdrop-filter .playlist-modal,
.no-backdrop-filter .api-modal {
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
}

.no-backdrop-filter .cassette-modal {
    background: rgba(0, 0, 0, 0.95);
}

.no-backdrop-filter .playlist-modal,
.no-backdrop-filter .api-modal {
    background: rgba(0, 0, 0, 0.95);
}

/* Firefox scrollbar styling */
* {
    scrollbar-width: thin;
    scrollbar-color: var(--bg-tertiary) var(--bg-primary);
}

/* Aspect ratio fallback for older browsers */
@supports not (aspect-ratio: 1) {
    .music-card-image {
        position: relative;
        padding-bottom: 100%;
        height: 0;
    }
    
    .music-card-image img {
        position: absolute;
        top: 0;
        left: 0;
    }
    
    .cassette-tape {
        position: relative;
        padding-bottom: 64%;
        height: 0;
    }
}

/* Progress slider visibility fix */
.progress-slider {
    opacity: 0;
}

.progress-slider:focus {
    opacity: 1;
    outline: 2px solid var(--accent-primary);
    outline-offset: 2px;
}

.progress-track:hover .progress-slider,
.progress-track:focus-within .progress-slider {
    opacity: 0.3;
}

/* ============================================
   ACCESSIBILITY IMPROVEMENTS
   ============================================ */

/* Focus visible for keyboard navigation */
*:focus-visible {
    outline: 2px solid var(--accent-primary);
    outline-offset: 2px;
}

button:focus-visible,
.nav-item:focus-visible {
    outline: 2px solid var(--accent-primary);
    outline-offset: -2px;
}

/* Skip to content link */
.skip-to-content {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--accent-primary);
    color: var(--text-primary);
    padding: 8px 16px;
    text-decoration: none;
    z-index: 10002;
    border-radius: 0 0 4px 0;
}

.skip-to-content:focus {
    top: 0;
}

/* Screen reader only text */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

/* ============================================
   LOADING STATES
   ============================================ */

.skeleton {
    background: linear-gradient(
        90deg,
        var(--bg-tertiary) 0%,
        var(--bg-hover) 50%,
        var(--bg-tertiary) 100%
    );
    background-size: 200% 100%;
    animation: skeleton-loading 1.5s ease-in-out infinite;
    border-radius: 4px;
}

@keyframes skeleton-loading {
    0% {
        background-position: 200% 0;
    }
    100% {
        background-position: -200% 0;
    }
}

.music-card.skeleton .music-card-image {
    background: var(--bg-tertiary);
}

.music-card.skeleton .music-card-title,
.music-card.skeleton .music-card-artist {
    height: 16px;
    background: var(--bg-tertiary);
    border-radius: 4px;
}

/* ============================================
   MOBILE NOTIFICATION ADJUSTMENTS
   ============================================ */

@media (max-width: 480px) {
    .custom-notification {
        top: 10px;
        right: 10px;
        left: 10px;
        min-width: auto;
        max-width: none;
    }
    
    @keyframes slideIn {
        from {
            transform: translateY(-100px);
            opacity: 0;
        }
        to {
            transform: translateY(0);
            opacity: 1;
        }
    }
    
    @keyframes slideOut {
        from {
            transform: translateY(0);
            opacity: 1;
        }
        to {
            transform: translateY(-100px);
            opacity: 0;
        }
    }
}

/* ============================================
   PERFORMANCE: Reduce animations on low-end devices
   ============================================ */

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* ============================================
   IMAGE LOADING OPTIMIZATION
   ============================================ */

.music-card-image img[src=""],
.track-thumbnail img[src=""] {
    background: var(--bg-tertiary);
    display: block;
}