:root {
    --primary-bg: #000000;
    --secondary-bg: #121212;
    --card-bg: rgba(255, 255, 255, 0.05);
    --text-primary: #ffffff;
    --text-secondary: #b3b3b3;
    --accent-color: #1db954;
    --accent-hover: #1ed760;
    --border-color: rgba(255, 255, 255, 0.1);
    --glass-bg: rgba(30, 30, 30, 0.7);
    --shadow: 0 8px 24px rgba(0, 0, 0, 0.4);
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 28px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

*::-webkit-scrollbar {
    display: none;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: var(--primary-bg);
    color: var(--text-primary);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.app-container {
    width: 100%;
    min-height: 100vh;
    position: relative;
    padding-bottom: 140px;
}

/* Navigation */
.bottom-nav {
    position: fixed;
    bottom: 80px;
    left: 20px;
    right: 20px;
    height: 60px;
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-radius: var(--radius-xl);
    display: flex;
    justify-content: space-around;
    align-items: center;
    padding: 0 var(--spacing-sm);
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
    z-index: 100;
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 4px;
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-md);
    transition: var(--transition);
    flex: 1;
}

.nav-item.active {
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.1);
}

.nav-icon {
    width: 24px;
    height: 24px;
    stroke-width: 2;
}

.nav-item span {
    font-size: 11px;
    font-weight: 600;
}

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

/* Pages */
.main-content {
    width: 100%;
    max-width: 100%;
    margin: 0 auto;
}

.page {
    display: none;
    width: 100%;
    animation: fadeIn 0.3s ease;
}

.page.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Hero Section */
.hero-section {
    position: relative;
    min-height: 60vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-xl);
    overflow: hidden;
}

.hero-gradient {
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at center,
        rgba(29, 185, 84, 0.15) 0%,
        rgba(29, 185, 84, 0.05) 40%,
        transparent 70%);
    animation: pulse 8s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.8; transform: scale(1.1); }
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
}

.hero-title {
    font-size: clamp(2rem, 8vw, 4rem);
    font-weight: 800;
    margin-bottom: var(--spacing-lg);
    letter-spacing: -2px;
}

.hero-play-btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    background: var(--accent-color);
    color: var(--primary-bg);
    border: none;
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: var(--radius-xl);
    font-size: 1.1rem;
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: 0 4px 16px rgba(29, 185, 84, 0.4);
}

.hero-play-btn:hover {
    background: var(--accent-hover);
    transform: scale(1.05);
}

.hero-play-btn:active {
    transform: scale(0.98);
}

.play-icon {
    width: 24px;
    height: 24px;
}

/* Content Sections */
.content-section {
    padding: var(--spacing-xl) var(--spacing-md);
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
}

.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.see-all-btn {
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: var(--spacing-sm);
    display: flex;
    align-items: center;
    transition: var(--transition);
}

.see-all-btn:hover {
    color: var(--text-primary);
}

.see-all-btn svg {
    width: 24px;
    height: 24px;
}

/* Release Card */
.new-releases {
    display: grid;
    gap: var(--spacing-md);
}

.release-card {
    position: relative;
    border-radius: var(--radius-lg);
    overflow: hidden;
    cursor: pointer;
    transition: var(--transition);
}

.release-card:hover {
    transform: scale(1.02);
}

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

.release-image {
    width: 100%;
    height: auto;
    display: block;
}

.release-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: var(--spacing-md);
    background: linear-gradient(to top, rgba(0,0,0,0.8), transparent);
    font-weight: 600;
}

/* Track List */
.track-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.track-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-sm);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
}

.track-item:hover {
    background: var(--card-bg);
}

.track-item:active {
    transform: scale(0.98);
}

.track-item.playing {
    background: rgba(29, 185, 84, 0.1);
}

.track-number {
    width: 24px;
    text-align: center;
    color: var(--text-secondary);
    font-weight: 600;
    font-size: 14px;
}

.track-cover {
    width: 52px;
    height: 52px;
    border-radius: var(--radius-sm);
    object-fit: cover;
}

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

.track-title {
    font-weight: 600;
    font-size: 15px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.track-artist {
    color: var(--text-secondary);
    font-size: 13px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.track-menu {
    color: var(--text-secondary);
    font-size: 20px;
    padding: var(--spacing-sm);
}

/* Search */
.search-header {
    position: sticky;
    top: 0;
    background: var(--primary-bg);
    padding: var(--spacing-md);
    z-index: 10;
}

.search-container {
    position: relative;
    margin-bottom: var(--spacing-md);
}

.search-icon {
    position: absolute;
    left: var(--spacing-md);
    top: 50%;
    transform: translateY(-50%);
    width: 20px;
    height: 20px;
    color: var(--text-secondary);
    pointer-events: none;
}

#searchInput {
    width: 100%;
    padding: var(--spacing-md) var(--spacing-md) var(--spacing-md) 48px;
    background: var(--glass-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-xl);
    color: var(--text-primary);
    font-size: 16px;
    outline: none;
    transition: var(--transition);
}

#searchInput:focus {
    border-color: var(--accent-color);
    background: var(--secondary-bg);
}

#searchInput::placeholder {
    color: var(--text-secondary);
}

.search-tabs {
    display: flex;
    gap: var(--spacing-sm);
}

.search-tab {
    flex: 1;
    padding: var(--spacing-sm) 0;
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-weight: 600;
    font-size: 14px;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
}

.search-tab.active {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
}

.search-results {
    padding: 0 var(--spacing-md) var(--spacing-md);
}

/* Profile */
.profile-header {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: var(--spacing-xl) var(--spacing-md);
    gap: var(--spacing-md);
}

.profile-avatar {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid var(--border-color);
}

.profile-username {
    font-size: 1.5rem;
    font-weight: 700;
}

.profile-menu {
    padding: 0 var(--spacing-md);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.profile-menu-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    text-decoration: none;
    color: var(--text-primary);
    transition: var(--transition);
}

.profile-menu-item:hover {
    background: var(--card-bg);
}

.profile-menu-item:active {
    transform: scale(0.98);
}

.menu-item-icon {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
}

.menu-item-icon.orange {
    background: #ff9500;
}

.menu-item-icon.blue {
    background: #007aff;
}

.profile-menu-item span {
    flex: 1;
    font-weight: 500;
}

.arrow {
    width: 20px;
    height: 20px;
    color: var(--text-secondary);
}

/* Playlist/Chart */
.playlist-header {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: var(--spacing-xl) var(--spacing-md);
    gap: var(--spacing-lg);
}

.playlist-cover {
    width: 90%;
    max-width: 300px;
    aspect-ratio: 1;
    border-radius: var(--radius-lg);
    object-fit: cover;
    box-shadow: var(--shadow);
}

.playlist-title {
    font-size: 2rem;
    font-weight: 800;
    text-align: center;
    letter-spacing: -1px;
}

.playlist-description {
    color: var(--text-secondary);
    text-align: center;
}

/* Artist Page */
.artist-header {
    position: relative;
    height: 50vh;
    overflow: hidden;
}

.artist-bg-image {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    filter: brightness(0.6);
}

.artist-header::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(to bottom, transparent 40%, var(--primary-bg) 100%);
}

.artist-info {
    position: absolute;
    bottom: var(--spacing-xl);
    left: var(--spacing-md);
    right: var(--spacing-md);
    z-index: 1;
}

.artist-name {
    font-size: 2.5rem;
    font-weight: 800;
    letter-spacing: -1px;
    margin-bottom: var(--spacing-sm);
}

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

.artist-content {
    padding: var(--spacing-lg) var(--spacing-md);
}

/* Album Page */
.album-header {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: var(--spacing-xl) var(--spacing-md);
    gap: var(--spacing-lg);
}

.album-cover {
    width: 90%;
    max-width: 280px;
    aspect-ratio: 1;
    border-radius: var(--radius-lg);
    object-fit: cover;
    box-shadow: var(--shadow);
}

.album-info {
    text-align: center;
}

.album-title {
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
}

.album-artist {
    color: var(--text-secondary);
    font-size: 1rem;
    margin-bottom: var(--spacing-xs);
}

.album-year {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Loading Spinner */
.spinner {
    width: 48px;
    height: 48px;
    border: 4px solid rgba(255, 255, 255, 0.1);
    border-top-color: var(--accent-color);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

.search-message {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-xl);
    color: var(--text-secondary);
    text-align: center;
}

/* Utility Classes */
.hidden {
    display: none !important;
}

.fade-in {
    animation: fadeIn 0.3s ease;
}

.fade-out {
    animation: fadeOut 0.3s ease;
}

@keyframes fadeOut {
    from {
        opacity: 1;
        transform: translateY(0);
    }
    to {
        opacity: 0;
        transform: translateY(10px);
    }
}

/* Scrollbar for desktop */
@media (min-width: 1024px) {
    ::-webkit-scrollbar {
        width: 8px;
        height: 8px;
    }

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

    ::-webkit-scrollbar-thumb {
        background: rgba(255, 255, 255, 0.2);
        border-radius: 4px;
    }

    ::-webkit-scrollbar-thumb:hover {
        background: rgba(255, 255, 255, 0.3);
    }
}

/* Smooth Transitions */
* {
    -webkit-tap-highlight-color: transparent;
    -webkit-touch-callout: none;
}

button, a {
    -webkit-user-select: none;
    user-select: none;
}

/* Focus States for Accessibility */
button:focus-visible,
a:focus-visible,
input:focus-visible {
    outline: 2px solid var(--accent-color);
    outline-offset: 2px;
}

/* Image Loading */
img {
    image-rendering: -webkit-optimize-contrast;
}

img:not([src]) {
    visibility: hidden;
}

/* Text Selection */
::selection {
    background: var(--accent-color);
    color: var(--primary-bg);
}

/* Artist/Album Grid Items */
.album-item,
.artist-item {
    transition: transform 0.2s ease;
}

.album-item:active,
.artist-item:active {
    transform: scale(0.95);
}

/* Empty State */
.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-xl);
    color: var(--text-secondary);
    text-align: center;
    min-height: 200px;
}

.empty-state svg {
    width: 64px;
    height: 64px;
    margin-bottom: var(--spacing-md);
    opacity: 0.5;
}