/* ── Variables ── */
:root {
    --ruby: #9b1c2e;
    --ruby-bright: #c0253b;
    --ruby-glow: #e0304a;
    --ruby-dim: #6b1220;

    --radius: 12px;
    --radius-sm: 8px;
    --transition: 0.2s ease;
}

[data-theme="dark"] {
    --bg: #0d0d0f;
    --surface: rgba(255,255,255,0.04);
    --surface-hover: rgba(255,255,255,0.07);
    --border: rgba(255,255,255,0.08);
    --text: #f0eef2;
    --text-muted: #8a8490;
    --text-dim: #5a5560;
    --glass-bg: rgba(18,16,22,0.7);
    --glass-border: rgba(255,255,255,0.07);
    --shadow: 0 8px 32px rgba(0,0,0,0.5);
    --active-bg: rgba(155,28,46,0.15);
    --active-border: rgba(155,28,46,0.5);
}

[data-theme="light"] {
    --bg: #f4f0f5;
    --surface: rgba(0,0,0,0.04);
    --surface-hover: rgba(0,0,0,0.07);
    --border: rgba(0,0,0,0.1);
    --text: #1a1520;
    --text-muted: #6b6070;
    --text-dim: #a09aaa;
    --glass-bg: rgba(255,252,255,0.75);
    --glass-border: rgba(0,0,0,0.08);
    --shadow: 0 8px 32px rgba(0,0,0,0.12);
    --active-bg: rgba(155,28,46,0.08);
    --active-border: rgba(155,28,46,0.35);
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif; background: var(--bg); color: var(--text); min-height: 100vh; overflow-x: hidden; transition: background var(--transition), color var(--transition); }

/* ── Background canvas with radial gradients ── */
.bg-canvas {
    position: fixed; inset: 0; z-index: 0; pointer-events: none;
    background:
        radial-gradient(ellipse 60% 50% at 15% 20%, rgba(155,28,46,0.18) 0%, transparent 70%),
        radial-gradient(ellipse 40% 60% at 85% 10%, rgba(192,37,59,0.12) 0%, transparent 65%),
        radial-gradient(ellipse 50% 40% at 70% 80%, rgba(107,18,32,0.2) 0%, transparent 60%),
        radial-gradient(ellipse 35% 55% at 30% 90%, rgba(155,28,46,0.1) 0%, transparent 55%),
        radial-gradient(ellipse 70% 30% at 50% 50%, rgba(80,10,20,0.08) 0%, transparent 80%);
    transition: opacity var(--transition);
}

[data-theme="light"] .bg-canvas {
    background:
        radial-gradient(ellipse 60% 50% at 15% 20%, rgba(155,28,46,0.1) 0%, transparent 70%),
        radial-gradient(ellipse 40% 60% at 85% 10%, rgba(192,37,59,0.07) 0%, transparent 65%),
        radial-gradient(ellipse 50% 40% at 70% 80%, rgba(107,18,32,0.12) 0%, transparent 60%),
        radial-gradient(ellipse 35% 55% at 30% 90%, rgba(155,28,46,0.06) 0%, transparent 55%),
        radial-gradient(ellipse 70% 30% at 50% 50%, rgba(80,10,20,0.04) 0%, transparent 80%);
}

/* ── App layout ── */
.app { position: relative; z-index: 1; max-width: 900px; margin: 0 auto; padding: 0 16px 48px; }

/* ── Header ── */
.app-header {
    display: flex; align-items: center; justify-content: space-between;
    padding: 20px 0 24px;
}
.header-left { display: flex; align-items: center; gap: 10px; }
.logo-icon { width: 28px; height: 28px; color: var(--ruby-bright); }
.logo-text { font-size: 1.2rem; font-weight: 700; letter-spacing: -0.02em; color: var(--text); }

.theme-toggle {
    background: var(--surface); border: 1px solid var(--border); border-radius: 50%;
    width: 38px; height: 38px; cursor: pointer; display: flex; align-items: center; justify-content: center;
    color: var(--text-muted); transition: all var(--transition);
}
.theme-toggle:hover { background: var(--surface-hover); color: var(--text); }
.icon-sun, .icon-moon { width: 18px; height: 18px; position: absolute; transition: opacity var(--transition), transform var(--transition); }
[data-theme="dark"] .icon-sun { opacity: 1; transform: rotate(0deg); }
[data-theme="dark"] .icon-moon { opacity: 0; transform: rotate(90deg); }
[data-theme="light"] .icon-sun { opacity: 0; transform: rotate(-90deg); }
[data-theme="light"] .icon-moon { opacity: 1; transform: rotate(0deg); }

/* ── Glass card ── */
.glass-card {
    background: var(--glass-bg); border: 1px solid var(--glass-border);
    border-radius: var(--radius); backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px);
    box-shadow: var(--shadow);
}

/* ── Filters ── */
.filters-panel { padding: 20px; margin-bottom: 16px; }
.filters-row { display: flex; flex-wrap: wrap; gap: 12px; align-items: flex-end; }
.filter-group { display: flex; flex-direction: column; gap: 6px; flex: 1; min-width: 140px; }
.filter-label { font-size: 0.72rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.06em; color: var(--text-muted); }

.filter-input, .filter-select {
    background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-sm);
    color: var(--text); padding: 8px 12px; font-size: 0.875rem; outline: none;
    transition: border-color var(--transition), background var(--transition);
    width: 100%;
}
.filter-input:focus, .filter-select:focus { border-color: var(--ruby-bright); background: var(--surface-hover); }
.filter-input::placeholder { color: var(--text-dim); }
.filter-select option { background: var(--bg); color: var(--text); }
.filter-input--sm { width: 90px; flex: 1; }
.duration-range { display: flex; align-items: center; gap: 6px; }
.range-sep { color: var(--text-dim); font-size: 0.8rem; }

/* ── Toolbar ── */
.toolbar { display: flex; align-items: center; justify-content: space-between; margin-bottom: 12px; flex-wrap: wrap; gap: 10px; }
.toolbar-actions { display: flex; gap: 8px; }
.stats-text { font-size: 0.8rem; color: var(--text-muted); }
.stats-text strong { color: var(--ruby-bright); }

/* ── Buttons ── */
.btn {
    border: none; border-radius: var(--radius-sm); padding: 9px 18px; font-size: 0.875rem;
    font-weight: 600; cursor: pointer; transition: all var(--transition); white-space: nowrap;
}
.btn--primary {
    background: linear-gradient(135deg, var(--ruby-bright), var(--ruby));
    color: #fff; box-shadow: 0 2px 12px rgba(155,28,46,0.4);
}
.btn--primary:hover { background: linear-gradient(135deg, var(--ruby-glow), var(--ruby-bright)); box-shadow: 0 4px 20px rgba(155,28,46,0.6); transform: translateY(-1px); }
.btn--primary:active { transform: translateY(0); }
.btn--secondary {
    background: var(--surface); border: 1px solid var(--border); color: var(--text);
}
.btn--secondary:hover { background: var(--surface-hover); border-color: var(--ruby-dim); color: var(--ruby-bright); }
.btn--ghost {
    background: transparent; border: 1px solid var(--border); color: var(--text-muted);
}
.btn--ghost:hover { border-color: var(--ruby-dim); color: var(--ruby-bright); }

/* ── Song list ── */
.song-list { display: flex; flex-direction: column; gap: 6px; }

.song-item {
    display: flex; align-items: center; gap: 12px;
    background: var(--surface); border: 1px solid var(--border);
    border-radius: var(--radius); padding: 12px 16px;
    cursor: pointer; transition: all var(--transition); user-select: none;
}
.song-item:hover { background: var(--surface-hover); border-color: var(--ruby-dim); }
.song-item.active {
    background: var(--active-bg); border-color: var(--active-border);
    box-shadow: 0 0 0 1px var(--active-border) inset;
}
.song-item.active .song-check { background: var(--ruby-bright); border-color: var(--ruby-bright); }
.song-item.active .song-check::after { opacity: 1; }

.song-check {
    width: 20px; height: 20px; border-radius: 6px; border: 2px solid var(--border);
    flex-shrink: 0; position: relative; transition: all var(--transition);
    background: transparent;
}
.song-check::after {
    content: ''; position: absolute; left: 4px; top: 1px;
    width: 6px; height: 10px; border: 2px solid #fff; border-top: none; border-left: none;
    transform: rotate(45deg); opacity: 0; transition: opacity var(--transition);
}

.song-info { flex: 1; min-width: 0; }
.song-title { font-size: 0.9rem; font-weight: 600; color: var(--text); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.song-artist { font-size: 0.78rem; color: var(--text-muted); margin-top: 2px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }

.song-meta { display: flex; align-items: center; gap: 8px; flex-shrink: 0; }
.song-genres { display: flex; flex-wrap: wrap; gap: 4px; justify-content: flex-end; }
.song-genre {
    font-size: 0.68rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.05em;
    padding: 2px 7px; border-radius: 20px; border: 1px solid;
    white-space: nowrap;
}
.song-duration { font-size: 0.78rem; color: var(--text-muted); font-variant-numeric: tabular-nums; min-width: 38px; text-align: right; }

/* ── Empty state ── */
.empty-state { text-align: center; padding: 60px 20px; color: var(--text-dim); }
.empty-state svg { width: 56px; height: 56px; margin-bottom: 12px; opacity: 0.4; }
.empty-state p { font-size: 0.9rem; }
.hidden { display: none !important; }

/* ── Notification ── */
.notification {
    position: fixed; bottom: 24px; right: 24px; z-index: 100;
    padding: 12px 20px; border-radius: var(--radius); font-size: 0.875rem; font-weight: 500;
    backdrop-filter: blur(12px); box-shadow: var(--shadow);
    animation: slideIn 0.3s ease;
    max-width: 320px;
}
.notification.success { background: rgba(30,120,60,0.85); border: 1px solid rgba(50,200,100,0.3); color: #d0ffd8; }
.notification.error { background: rgba(120,20,30,0.85); border: 1px solid rgba(200,50,70,0.3); color: #ffd0d5; }

@keyframes slideIn {
    from { opacity: 0; transform: translateY(12px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ── Responsive ── */
@media (max-width: 600px) {
    .filters-row { flex-direction: column; }
    .filter-group { min-width: unset; }
    .song-genres { display: none; }
    .toolbar { flex-direction: column; align-items: flex-start; }
}

/* ── Playlist panel ── */
.playlist-panel { padding: 20px; margin-top: 24px; }
.playlist-header { margin-bottom: 14px; }
.playlist-title { font-size: 0.85rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em; color: var(--text-muted); }
.playlist-save-row { display: flex; gap: 10px; margin-bottom: 14px; flex-wrap: wrap; }
.playlist-save-row .filter-input { flex: 1; min-width: 160px; }

.playlist-list { display: flex; flex-direction: column; gap: 6px; }
.playlist-empty { font-size: 0.82rem; color: var(--text-dim); padding: 8px 0; }

.playlist-row {
    display: flex; align-items: center; justify-content: space-between; gap: 12px;
    background: var(--surface); border: 1px solid var(--border);
    border-radius: var(--radius-sm); padding: 10px 14px;
    transition: background var(--transition);
}
.playlist-row:hover { background: var(--surface-hover); }
.playlist-row-info { display: flex; flex-direction: column; gap: 2px; min-width: 0; }
.playlist-row-name { font-size: 0.875rem; font-weight: 600; color: var(--text); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.playlist-row-count { font-size: 0.75rem; color: var(--text-muted); }
.playlist-row-actions { display: flex; gap: 6px; flex-shrink: 0; }

.btn--xs { padding: 5px 10px; font-size: 0.78rem; }
.btn--danger { color: var(--ruby-bright) !important; border-color: var(--ruby-dim) !important; }
.btn--danger:hover { background: rgba(155,28,46,0.12) !important; }