:root {
    --primary-bg: #0f172a;
    --glass-bg: rgba(30, 41, 59, 0.7);
    --glass-border: rgba(255, 255, 255, 0.1);
    --accent-color: #3b82f6;
    --accent-hover: #2563eb;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --gradient-1: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%);
    --gradient-btn: linear-gradient(135deg, #f43f5e 0%, #d946ef 100%);
}

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

body {
    font-family: 'Outfit', sans-serif;
    background-color: var(--primary-bg);
    color: var(--text-primary);
    overflow-x: hidden;
    min-height: 100vh;
}

.background-anim {
    position: fixed;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at 50% 50%, rgba(59, 130, 246, 0.15), transparent 60%),
                radial-gradient(circle at 80% 20%, rgba(139, 92, 246, 0.15), transparent 50%);
    z-index: -1;
    animation: drift 20s linear infinite alternate;
}

@keyframes drift {
    0% { transform: translate(0, 0); }
    100% { transform: translate(5%, 5%); }
}

.glass-panel {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    padding: 24px;
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.1);
}

/* Typography */
h1, h2, h3 {
    font-weight: 600;
    margin-bottom: 8px;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 20px;
}

/* Login Page */
.login-body {
    display: flex;
    justify-content: center;
    align-items: center;
}

.login-container {
    width: 100%;
    max-width: 400px;
    text-align: center;
}

.input-group {
    margin-bottom: 20px;
    text-align: left;
}

.input-group label {
    display: block;
    margin-bottom: 8px;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.input-group input {
    width: 100%;
    padding: 12px 16px;
    border-radius: 8px;
    border: 1px solid var(--glass-border);
    background: rgba(15, 23, 42, 0.5);
    color: var(--text-primary);
    font-family: inherit;
    transition: border-color 0.3s;
}

.input-group input:focus {
    outline: none;
    border-color: var(--accent-color);
}

.btn-primary {
    width: 100%;
    padding: 12px;
    border-radius: 8px;
    border: none;
    background: var(--gradient-1);
    color: white;
    font-family: inherit;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.4);
}

.error-banner {
    background: rgba(239, 68, 68, 0.2);
    border: 1px solid rgba(239, 68, 68, 0.4);
    color: #fca5a5;
    padding: 12px;
    border-radius: 8px;
    margin-bottom: 20px;
}

/* Main App Nav */
.top-nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 32px;
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--glass-border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.mode-switch {
    display: flex;
    align-items: center;
    gap: 12px;
}

.mode-label {
    font-size: 0.9rem;
    color: var(--text-secondary);
    transition: color 0.3s;
}

.mode-label.active {
    color: var(--text-primary);
    font-weight: 600;
}

.switch {
    position: relative;
    display: inline-block;
    width: 50px;
    height: 24px;
}

.switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--glass-border);
    transition: .4s;
}

.slider:before {
    position: absolute;
    content: "";
    height: 18px;
    width: 18px;
    left: 3px;
    bottom: 3px;
    background-color: white;
    transition: .4s;
}

input:checked + .slider {
    background: var(--gradient-1);
}

input:checked + .slider:before {
    transform: translateX(26px);
}

.slider.round {
    border-radius: 24px;
}

.slider.round:before {
    border-radius: 50%;
}

.btn-logout {
    color: var(--text-secondary);
    text-decoration: none;
    margin-left: 16px;
    font-size: 0.9rem;
}
.btn-logout:hover {
    color: white;
}

/* Main Content Grid */
.main-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 32px;
    padding-bottom: 120px;
}

.special-songs-section {
    margin-bottom: 24px;
    text-align: center;
}

.big-buttons {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-top: 20px;
    flex-wrap: wrap;
}

.big-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 180px;
    height: 120px;
    border: none;
    border-radius: 16px;
    cursor: pointer;
    transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275), box-shadow 0.3s;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--glass-border);
    color: white;
}

.big-btn:hover {
    transform: translateY(-5px) scale(1.05);
}

.big-btn.birthday-btn {
    background: var(--gradient-btn);
    border: none;
}

.big-btn.birthday-btn:hover {
    box-shadow: 0 10px 25px rgba(244, 63, 94, 0.4);
}

.big-btn.custom-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

.big-btn .icon {
    font-size: 2.5rem;
    margin-bottom: 8px;
}

.big-btn .text {
    font-family: inherit;
    font-weight: 600;
}

.layout-grid {
    display: grid;
    grid-template-columns: 250px 1fr;
    gap: 24px;
}

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

.category-item {
    padding: 12px 16px;
    border-radius: 8px;
    cursor: pointer;
    transition: background 0.2s, color 0.2s;
    color: var(--text-secondary);
}

.category-item:hover {
    background: rgba(255, 255, 255, 0.05);
    color: white;
}

.category-item.active {
    background: var(--gradient-1);
    color: white;
    font-weight: 600;
}

.playlist-container {
    height: 400px;
    overflow-y: auto;
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}
::-webkit-scrollbar-track {
    background: rgba(0,0,0,0.1);
}
::-webkit-scrollbar-thumb {
    background: var(--glass-border);
    border-radius: 4px;
}

.track-item {
    display: flex;
    align-items: center;
    padding: 12px;
    border-radius: 8px;
    cursor: pointer;
    transition: background 0.2s;
    border-bottom: 1px solid rgba(255, 255, 255, 0.02);
}

.track-item:hover {
    background: rgba(255, 255, 255, 0.05);
}

.track-item.playing {
    background: rgba(59, 130, 246, 0.15);
    border: 1px solid rgba(59, 130, 246, 0.3);
}

.track-item.playing .indicator {
    display: inline-block !important;
    animation: pulse 1s infinite alternate;
}

@keyframes pulse {
    from { opacity: 0.5; }
    to { opacity: 1; }
}

.track-item img {
    width: 40px;
    height: 40px;
    border-radius: 4px;
    margin-right: 16px;
}

.track-item .info {
    flex-grow: 1;
}

.track-item .info .title {
    font-weight: 600;
    margin-bottom: 4px;
    font-size: 0.95rem;
}

.track-item .info .artist {
    color: var(--text-secondary);
    font-size: 0.8rem;
}

.track-item .duration {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

/* Bottom Player */
.bottom-player {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%);
    width: calc(100% - 48px);
    max-width: 1200px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 24px;
    z-index: 1000;
}

.now-playing {
    display: flex;
    align-items: center;
    width: 30%;
}

.track-cover {
    width: 56px;
    height: 56px;
    border-radius: 8px;
    margin-right: 16px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.track-info .track-name {
    font-weight: 600;
    margin-bottom: 4px;
}

.track-info .track-artist {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

.player-controls {
    display: flex;
    align-items: center;
    gap: 16px;
}

.control-btn {
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 1.5rem;
    cursor: pointer;
    transition: color 0.2s, transform 0.2s;
}

.control-btn:disabled {
    color: var(--text-secondary);
    opacity: 0.5;
    cursor: not-allowed;
}

.control-btn:not(:disabled):hover {
    color: var(--accent-color);
    transform: scale(1.1);
}

.big-btn.mic-btn {
    border: 2px solid transparent;
    transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.big-btn.mic-btn.recording {
    border-color: #ef4444;
    background: rgba(239, 68, 68, 0.2);
    color: #fca5a5;
    animation: micPulse 1s infinite alternate, micRipple 1.5s infinite;
}

@keyframes micRipple {
    0% { box-shadow: 0 0 0 0 rgba(239, 68, 68, 0.4); }
    70% { box-shadow: 0 0 0 20px rgba(239, 68, 68, 0); }
    100% { box-shadow: 0 0 0 0 rgba(239, 68, 68, 0); }
}

@keyframes micPulse {
    from { transform: scale(1); }
    to { transform: scale(1.05); }
}

.play-btn {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: white;
    color: var(--primary-bg);
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.2rem;
}

.play-btn:not(:disabled):hover {
    background: var(--accent-color);
    color: white;
}

.progress-container {
    width: 25%;
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.volume-container {
    display: flex;
    align-items: center;
    gap: 8px;
    width: 15%;
    color: var(--text-secondary);
}

.progress-bar {
    flex-grow: 1;
    -webkit-appearance: none;
    appearance: none;
    height: 4px;
    background: var(--glass-border);
    border-radius: 2px;
    outline: none;
}

.progress-bar::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: white;
    cursor: pointer;
    transition: transform 0.2s;
}

.progress-bar::-webkit-slider-thumb:hover {
    transform: scale(1.3);
    background: var(--accent-color);
}

/* Toasts */
.toast-container {
    position: fixed;
    top: 24px;
    right: 24px;
    z-index: 2000;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.toast {
    background: rgba(15, 23, 42, 0.9);
    border: 1px solid var(--glass-border);
    backdrop-filter: blur(8px);
    color: white;
    padding: 12px 20px;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
    display: flex;
    align-items: center;
    gap: 12px;
    animation: slideIn 0.3s ease-out forwards;
    opacity: 0;
    transform: translateX(100%);
}

.toast.fade-out {
    animation: fadeOut 0.5s ease-in forwards;
}

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

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

@media (max-width: 768px) {
    /* Header (Top Nav) Mobile Fixes */
    .top-nav {
        flex-wrap: wrap;
        padding: 16px;
        gap: 12px;
    }
    .logo {
        flex: 1 1 auto;
        font-size: 1.3rem;
    }
    .user-info {
        flex: 1 1 auto;
        display: flex;
        justify-content: flex-end;
        align-items: center;
        font-size: 0.9rem;
    }
    .mode-switch {
        flex: 1 1 100%;
        order: 3;
        justify-content: center;
        margin-top: 8px;
        padding-top: 16px;
        border-top: 1px solid var(--glass-border);
    }
    
    /* Layout Grid */
    .layout-grid {
        grid-template-columns: 1fr;
    }
    
    /* Bottom Player Mobile */
    .bottom-player {
        flex-direction: row;
        flex-wrap: wrap;
        gap: 12px;
        padding: 12px;
        width: calc(100% - 24px);
        bottom: 12px;
    }
    .now-playing {
        width: calc(100% - 150px);
        justify-content: flex-start;
    }
    .track-cover {
        width: 44px;
        height: 44px;
        margin-right: 12px;
    }
    .track-info .track-name {
        font-size: 0.95rem;
        margin-bottom: 2px;
        white-space: nowrap;
        overflow: hidden;
        text-overflow: ellipsis;
    }
    .track-info .track-artist {
        font-size: 0.8rem;
    }
    .player-controls {
        width: auto;
        justify-content: flex-end;
        gap: 8px;
    }
    .progress-container {
        width: 100%;
        margin-top: 4px;
    }
    
    .volume-container {
        width: 100%;
        margin-top: 4px;
        gap: 8px;
    }
}