/* ═══════════════════════════════════════════════════════════════
   SpotMp3.org — Design System
   Dark-first, with light mode toggle via [data-theme="light"]
   ═══════════════════════════════════════════════════════════════ */

/* ── Reset ──────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; overflow-x: clip; }
body { min-height: 100vh; line-height: 1.6; -webkit-font-smoothing: antialiased; overflow-x: clip; }
img, svg { display: block; max-width: 100%; }
button, input, textarea { font: inherit; color: inherit; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }

/* ── Dark Theme (default) ──────────────────────────────────── */
:root {
  /* Backgrounds */
  --bg-primary: #0a0a12;
  --bg-secondary: #0f0f1a;
  --bg-card: rgba(255, 255, 255, 0.04);
  --bg-card-hover: rgba(255, 255, 255, 0.08);
  --bg-card-solid: #13131f;
  --bg-input: rgba(255, 255, 255, 0.06);
  --bg-overlay: rgba(0, 0, 0, 0.7);
  --bg-toast: rgba(15, 15, 26, 0.95);

  /* Accents */
  --accent-purple: #7c3aed;
  --accent-purple-hover: #6d28d9;
  --accent-blue: #3b82f6;
  --accent-green: #10b981;
  --accent-green-hover: #059669;
  --accent-red: #ef4444;
  --accent-red-hover: #dc2626;
  --accent-yellow: #f59e0b;
  --accent-gold: #d4a017;

  /* Text */
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-dim: #475569;
  --text-inverse: #0a0a12;

  /* Borders */
  --border-glass: rgba(255, 255, 255, 0.1);
  --border-glass-hover: rgba(255, 255, 255, 0.2);
  --border-accent: rgba(124, 58, 237, 0.4);

  /* Glows */
  --glow-purple: 0 0 20px rgba(124, 58, 237, 0.3);
  --glow-purple-strong: 0 0 40px rgba(124, 58, 237, 0.4);
  --glow-blue: 0 0 20px rgba(59, 130, 246, 0.3);
  --glow-green: 0 0 20px rgba(16, 185, 129, 0.3);
  --glow-red: 0 0 20px rgba(239, 68, 68, 0.3);

  /* Radii */
  --radius-xs: 6px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 20px;
  --radius-pill: 999px;

  /* Spacing */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-2xl: 48px;
  --space-3xl: 64px;

  /* Typography */
  --font-primary: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  --fs-xs: 0.75rem;
  --fs-sm: 0.875rem;
  --fs-base: 1rem;
  --fs-md: 1.125rem;
  --fs-lg: 1.25rem;
  --fs-xl: 1.5rem;
  --fs-2xl: 2rem;
  --fs-3xl: 2.5rem;
  --fs-hero: clamp(2rem, 5vw, 3.5rem);

  --fw-normal: 400;
  --fw-medium: 500;
  --fw-semibold: 600;
  --fw-bold: 700;
  --fw-extrabold: 800;

  /* Transitions */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-bounce: cubic-bezier(0.34, 1.56, 0.64, 1);
  --duration-fast: 150ms;
  --duration-normal: 250ms;
  --duration-slow: 400ms;

  /* Z-index scale */
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-modal-overlay: 500;
  --z-modal: 600;
  --z-toast: 700;

  /* Misc */
  --navbar-height: 64px;
  --max-width: 1200px;
  --content-width: 720px;
}

/* ── Light Theme ───────────────────────────────────────────── */
[data-theme="light"] {
  --bg-primary: #e3e8ec;
  --bg-secondary: #e8ebee;
  --bg-card: rgba(0, 0, 0, 0.03);
  --bg-card-hover: rgba(0, 0, 0, 0.06);
  --bg-card-solid: #ffffff;
  --bg-input: rgba(0, 0, 0, 0.04);
  --bg-overlay: rgba(255, 255, 255, 0.8);
  --bg-toast: rgba(255, 255, 255, 0.95);

  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-dim: #94a3b8;
  --text-inverse: #f1f5f9;
  --border-glass: rgba(0, 0, 0, 0.08);
  --border-glass-hover: rgba(0, 0, 0, 0.15);
  --border-accent: rgba(124, 58, 237, 0.25);
  --glow-purple: 0 2px 12px rgba(124, 58, 237, 0.15);
  --glow-purple-strong: 0 4px 24px rgba(124, 58, 237, 0.2);
  --glow-blue: 0 2px 12px rgba(59, 130, 246, 0.15);
  --glow-green: 0 2px 12px rgba(16, 185, 129, 0.15);
  --glow-red: 0 2px 12px rgba(239, 68, 68, 0.15);
}

[data-theme="light"] .footer__disclaimer {
  color: rgb(44, 28, 28);
}

[data-theme="light"] .footer__copy {
  color: rgb(24, 16, 16);
}

/* ── Base Styles ───────────────────────────────────────────── */
body {
  font-family: var(--font-primary);
  font-size: var(--fs-base);
  color: var(--text-primary);
  background: var(--bg-primary);
  transition: background var(--duration-slow) var(--ease-out),
              color var(--duration-slow) var(--ease-out);
}

/* ── Typography ────────────────────────────────────────────── */
h1, h2, h3, h4, h5, h6 {
  line-height: 1.2;
  font-weight: var(--fw-bold);
  letter-spacing: -0.02em;
}

.text-gradient {
  background: linear-gradient(135deg, var(--accent-purple), var(--accent-blue));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ── Glass Effect Utility ──────────────────────────────────── */
.glass {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-radius: var(--radius-lg);
}

.glass-strong {
  background: var(--bg-card-solid);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
}

/* ── Container ─────────────────────────────────────────────── */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

.container--narrow {
  max-width: var(--content-width);
}

/* ── Buttons ───────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-lg);
  font-size: var(--fs-sm);
  font-weight: var(--fw-semibold);
  border: none;
  border-radius: var(--radius-pill);
  cursor: pointer;
  transition: all var(--duration-normal) var(--ease-out);
  white-space: normal;
  line-height: 1.4;
  text-align: center;
  user-select: none;
}

.btn--primary {
  background: linear-gradient(135deg, var(--accent-purple), var(--accent-blue));
  color: #fff;
  box-shadow: var(--glow-purple);
}
.btn--primary:hover {
  transform: translateY(-1px);
  box-shadow: var(--glow-purple-strong);
}
.btn--primary:active { transform: translateY(0); }

.btn--success {
  background: linear-gradient(135deg, var(--accent-green), #059669);
  color: #fff;
  box-shadow: var(--glow-green);
}
.btn--success:hover {
  transform: translateY(-1px);
  box-shadow: 0 0 30px rgba(16, 185, 129, 0.4);
}

.btn--danger {
  background: linear-gradient(135deg, var(--accent-red), #dc2626);
  color: #fff;
  box-shadow: var(--glow-red);
}

.btn--ghost {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid var(--border-glass);
}
.btn--ghost:hover {
  background: var(--bg-card-hover);
  color: var(--text-primary);
  border-color: var(--border-glass-hover);
}

.btn--lg {
  padding: var(--space-md) var(--space-xl);
  font-size: var(--fs-base);
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none !important;
}

/* ── Animations ────────────────────────────────────────────── */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

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

@keyframes slideUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes slideInRight {
  from { opacity: 0; transform: translateX(100%); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes slideOutRight {
  from { opacity: 1; transform: translateX(0); }
  to { opacity: 0; transform: translateX(100%); }
}

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

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

@keyframes progressGlow {
  0%, 100% { box-shadow: 0 0 8px rgba(124, 58, 237, 0.4); }
  50% { box-shadow: 0 0 20px rgba(124, 58, 237, 0.7); }
}

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

@keyframes confettiDrop {
  0% { transform: translateY(-100%) rotate(0deg); opacity: 1; }
  100% { transform: translateY(100vh) rotate(720deg); opacity: 0; }
}

@keyframes countUp {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-6px); }
}

.animate-fade-in { animation: fadeIn var(--duration-slow) var(--ease-out) forwards; }
.animate-slide-up { animation: slideUp var(--duration-slow) var(--ease-out) forwards; }
.animate-pulse { animation: pulse 2s ease-in-out infinite; }
.animate-spin { animation: spin 1s linear infinite; }
.animate-float { animation: float 3s ease-in-out infinite; }

/* ── Scrollbar ─────────────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb {
  background: var(--border-glass);
  border-radius: var(--radius-pill);
}
::-webkit-scrollbar-thumb:hover { background: var(--border-glass-hover); }

/* ── Selection ─────────────────────────────────────────────── */
::selection {
  background: rgba(124, 58, 237, 0.3);
  color: var(--text-primary);
}

/* ── Focus visible ─────────────────────────────────────────── */
:focus-visible {
  outline: 2px solid var(--accent-purple);
  outline-offset: 2px;
}

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

/* ── Responsive Helpers ────────────────────────────────────── */
.hide-mobile { display: none; }
@media (min-width: 640px) { .hide-mobile { display: initial; } }
@media (min-width: 640px) { .hide-desktop { display: none; } }