/* ============================================================
   main.css — Design System & Global Styles
   PhotoPerfect — Gamified Camera Learning App
   ============================================================ */

/* ── Google Fonts ─────────────────────────────────────────── */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&family=JetBrains+Mono:wght@400;500&display=swap');

/* ── CSS Custom Properties ─────────────────────────────────── */
:root {
  /* Core Palette */
  --bg-base: #07080f;
  --bg-surface: #0e0f1a;
  --bg-card: rgba(255,255,255,0.04);
  --bg-card-hover: rgba(255,255,255,0.07);
  --bg-glass: rgba(14,15,26,0.7);

  /* Accent */
  --accent: #7c3aed;
  --accent-light: #a78bfa;
  --accent-glow: rgba(124,58,237,0.4);

  /* Status */
  --success: #10b981;
  --success-glow: rgba(16,185,129,0.3);
  --warning: #f59e0b;
  --warning-glow: rgba(245,158,11,0.3);
  --danger: #ef4444;
  --danger-glow: rgba(239,68,68,0.3);

  /* Text */
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #475569;

  /* Borders */
  --border: rgba(255,255,255,0.08);
  --border-accent: rgba(124,58,237,0.4);

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;

  /* Radius */
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.3);
  --shadow-md: 0 8px 32px rgba(0,0,0,0.4);
  --shadow-lg: 0 24px 64px rgba(0,0,0,0.5);
  --shadow-glow: 0 0 32px var(--accent-glow);

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

  /* Nav */
  --nav-width: 72px;
  --nav-expanded: 220px;

  /* Transitions */
  --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
  --ease-smooth: cubic-bezier(0.4, 0, 0.2, 1);
}

/* ── Retro Film Theme ──────────────────────────────────────── */
[data-theme="retro_film"] {
  --bg-base: #1a1209;
  --bg-surface: #231810;
  --bg-card: rgba(255,220,150,0.04);
  --bg-card-hover: rgba(255,220,150,0.08);
  --bg-glass: rgba(35,24,16,0.75);
  --accent: #d97706;
  --accent-light: #fbbf24;
  --accent-glow: rgba(217,119,6,0.4);
  --text-primary: #fef3c7;
  --text-secondary: #b45309;
  --border: rgba(255,200,100,0.1);
  --border-accent: rgba(217,119,6,0.4);
}

/* ── Neon Theme ────────────────────────────────────────────── */
[data-theme="neon"] {
  --bg-base: #050510;
  --bg-surface: #0a0a20;
  --bg-card: rgba(180,0,255,0.04);
  --bg-glass: rgba(5,5,16,0.8);
  --accent: #c026d3;
  --accent-light: #e879f9;
  --accent-glow: rgba(192,38,211,0.5);
  --success: #00ff88;
  --warning: #ffcc00;
  --border: rgba(200,0,255,0.15);
}

/* ── Studio White Theme ────────────────────────────────────── */
[data-theme="minimal"] {
  --bg-base: #f8fafc;
  --bg-surface: #ffffff;
  --bg-card: rgba(0,0,0,0.03);
  --bg-card-hover: rgba(0,0,0,0.06);
  --bg-glass: rgba(248,250,252,0.85);
  --accent: #6d28d9;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --border: rgba(0,0,0,0.08);
}

/* ── Reset & Base ──────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  background: var(--bg-base);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  overflow-x: hidden;
  transition: background 0.4s ease, color 0.4s ease;
}

/* ── Scrollbar ─────────────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--bg-base); }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: var(--radius-full); }
::-webkit-scrollbar-thumb:hover { background: var(--accent); }

/* ── Glass Card ────────────────────────────────────────────── */
.glass-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  transition: background 0.2s ease, border-color 0.2s ease, transform 0.2s var(--ease-smooth), box-shadow 0.2s ease;
}

.glass-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-accent);
}

/* ── Sidebar Navigation ────────────────────────────────────── */
#sidebar {
  width: var(--nav-width);
  min-height: 100vh;
  background: var(--bg-surface);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: var(--space-lg) 0;
  position: sticky;
  top: 0;
  z-index: 100;
  flex-shrink: 0;
  transition: width 0.3s var(--ease-smooth);
  overflow: hidden;
}

.sidebar-logo {
  width: 44px;
  height: 44px;
  background: linear-gradient(135deg, var(--accent), var(--accent-light));
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: var(--space-xl);
  box-shadow: var(--shadow-glow);
  flex-shrink: 0;
  cursor: pointer;
  transition: transform 0.2s var(--ease-spring);
}
.sidebar-logo:hover { transform: scale(1.1); }

.sidebar-nav {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
  width: 100%;
  padding: 0 var(--space-sm);
}

.nav-link {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 12px;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease, transform 0.15s ease;
  white-space: nowrap;
  overflow: hidden;
  border: none;
  background: transparent;
  width: 100%;
}

.nav-link:hover {
  background: var(--bg-card);
  color: var(--text-primary);
  transform: translateX(2px);
}

.nav-link.active {
  background: var(--accent-glow);
  color: var(--accent-light);
  border: 1px solid var(--border-accent);
}

.nav-icon { font-size: 1.3rem; flex-shrink: 0; width: 24px; text-align: center; }
.nav-label { opacity: 0; transition: opacity 0.2s ease; pointer-events: none; }

.sidebar-bottom {
  margin-top: auto;
  padding: 0 var(--space-sm);
  width: 100%;
}

/* ── Main Content ──────────────────────────────────────────── */
#app-wrap {
  flex: 1;
  min-height: 100vh;
  overflow-y: auto;
  background: var(--bg-base);
  position: relative;
}

/* Star field background */
#app-wrap::before {
  content: '';
  position: fixed;
  inset: 0;
  background:
    radial-gradient(ellipse at 20% 20%, rgba(124,58,237,0.08) 0%, transparent 60%),
    radial-gradient(ellipse at 80% 80%, rgba(16,185,129,0.05) 0%, transparent 60%);
  pointer-events: none;
  z-index: 0;
}

#main-content {
  position: relative;
  z-index: 1;
  min-height: 100vh;
  padding: var(--space-xl);
}

/* ── Page Transition ───────────────────────────────────────── */
.page-enter {
  animation: pageEnter 0.35s var(--ease-smooth) both;
}

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

/* ── Buttons ───────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 0.6rem 1.25rem;
  border-radius: var(--radius-md);
  border: none;
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.15s var(--ease-spring), box-shadow 0.15s ease, filter 0.15s ease;
  text-decoration: none;
  white-space: nowrap;
}

.btn:hover { transform: translateY(-1px); }
.btn:active { transform: translateY(0) scale(0.98); }

.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-light));
  color: #fff;
  box-shadow: 0 4px 16px var(--accent-glow);
}
.btn-primary:hover { box-shadow: 0 8px 24px var(--accent-glow); filter: brightness(1.1); }

.btn-accent {
  background: linear-gradient(135deg, var(--success), #059669);
  color: #fff;
  box-shadow: 0 4px 16px var(--success-glow);
}

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

.btn-sm { padding: 0.4rem 0.85rem; font-size: 0.8rem; }

.btn-shoot {
  width: 100%;
  justify-content: center;
  padding: 1rem;
  font-size: 1.1rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--accent) 0%, #c026d3 100%);
  color: #fff;
  border-radius: var(--radius-md);
  box-shadow: 0 4px 24px var(--accent-glow);
  letter-spacing: 0.05em;
  margin-top: var(--space-md);
}
.btn-shoot:hover { box-shadow: 0 8px 36px var(--accent-glow); filter: brightness(1.1); }
.shoot-icon { font-size: 1.4rem; }

/* ── Tags ──────────────────────────────────────────────────── */
.tag {
  display: inline-block;
  padding: 2px 10px;
  border-radius: var(--radius-full);
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background: rgba(255,255,255,0.07);
  color: var(--text-secondary);
  border: 1px solid var(--border);
}

.tag-success { background: var(--success-glow); color: var(--success); border-color: var(--success); }
.tag-timed { background: var(--warning-glow); color: var(--warning); border-color: var(--warning); }
.tag-new { background: var(--accent-glow); color: var(--accent-light); }

/* ── XP Badge ──────────────────────────────────────────────── */
.xp-badge {
  display: inline-block;
  padding: 2px 8px;
  background: var(--warning-glow);
  color: var(--warning);
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 700;
  border: 1px solid rgba(245,158,11,0.3);
}

/* ── Section Headers ───────────────────────────────────────── */
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-md);
}

.section-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}

.section-sub {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.page-header {
  text-align: center;
  margin-bottom: var(--space-xl);
}

.page-title {
  font-size: 2rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--text-primary), var(--accent-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: var(--space-xs);
}

.page-sub {
  color: var(--text-secondary);
  font-size: 1rem;
}

/* ── Toast Container ───────────────────────────────────────── */
#toast-container {
  position: fixed;
  bottom: var(--space-xl);
  right: var(--space-xl);
  z-index: 9999;
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.toast {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 0.75rem 1.25rem;
  border-radius: var(--radius-md);
  background: var(--bg-surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-md);
  font-size: 0.875rem;
  font-weight: 500;
  min-width: 220px;
  max-width: 360px;
  transform: translateX(120%);
  opacity: 0;
  transition: transform 0.3s var(--ease-spring), opacity 0.3s ease;
}

.toast-visible { transform: translateX(0); opacity: 1; }

.toast-success { border-color: var(--success); }
.toast-error   { border-color: var(--danger); }
.toast-xp      { border-color: var(--warning); }

.toast-icon { font-size: 1.1rem; }

/* ── Badge Unlock Overlay ──────────────────────────────────── */
.badge-unlock-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.7);
  backdrop-filter: blur(8px);
  z-index: 10000;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.badge-unlock-overlay.visible { opacity: 1; }

.badge-unlock-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-accent);
  border-radius: var(--radius-xl);
  padding: var(--space-2xl);
  text-align: center;
  max-width: 400px;
  width: 90%;
  box-shadow: var(--shadow-lg), var(--shadow-glow);
  transform: scale(0.85);
  transition: transform 0.4s var(--ease-spring);
}

.badge-unlock-overlay.visible .badge-unlock-card { transform: scale(1); }

.badge-unlock-icon { font-size: 4rem; margin-bottom: var(--space-md); display: block; }
.badge-unlock-label { font-size: 0.8rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.1em; color: var(--warning); margin-bottom: var(--space-xs); }
.badge-unlock-name { font-size: 1.5rem; font-weight: 800; color: var(--text-primary); margin-bottom: var(--space-sm); }
.badge-unlock-desc { color: var(--text-secondary); font-size: 0.9rem; margin-bottom: var(--space-lg); }

.level-up-burst { font-size: 5rem; animation: burst 0.6s var(--ease-spring); margin-bottom: var(--space-md); }
@keyframes burst { 0% { transform: scale(0) rotate(-20deg); } 100% { transform: scale(1) rotate(0); } }

/* ── Particles ─────────────────────────────────────────────── */
.particle {
  position: fixed;
  border-radius: 50%;
  pointer-events: none;
  z-index: 11000;
  animation: particleFly var(--duration, 800ms) ease-out forwards;
  transform-origin: center;
}

@keyframes particleFly {
  0%   { transform: translate(0,0) scale(1); opacity: 1; }
  100% { transform: translate(var(--tx), var(--ty)) scale(0); opacity: 0; }
}

/* ── XP Bar ────────────────────────────────────────────────── */
.xp-bar-wrap { margin-top: var(--space-sm); }

.xp-bar-track {
  height: 8px;
  background: rgba(255,255,255,0.08);
  border-radius: var(--radius-full);
  overflow: hidden;
  position: relative;
}

.xp-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), var(--accent-light), var(--warning));
  border-radius: var(--radius-full);
  transition: width 0.8s var(--ease-smooth);
  box-shadow: 0 0 12px var(--accent-glow);
  background-size: 200% 100%;
  animation: shimmer 2s linear infinite;
}

@keyframes shimmer {
  0%   { background-position: 0% 50%; }
  100% { background-position: 200% 50%; }
}

.xp-label {
  display: flex;
  justify-content: space-between;
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 4px;
}

/* ── Difficulty Stars ──────────────────────────────────────── */
.difficulty-stars {
  color: var(--warning);
  font-size: 0.85rem;
  letter-spacing: 1px;
}

/* ── Error Page ────────────────────────────────────────────── */
.error-page {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-md);
  min-height: 60vh;
  text-align: center;
  color: var(--text-secondary);
}

/* ── Responsive ────────────────────────────────────────────── */
@media (max-width: 768px) {
  #sidebar { display: none; }
  #main-content { padding: var(--space-md); }
  #mobile-nav { display: flex !important; }
}

/* ── Mobile Bottom Nav ─────────────────────────────────────── */
#mobile-nav {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: var(--bg-surface);
  border-top: 1px solid var(--border);
  z-index: 200;
  padding: var(--space-sm) 0;
}

.mobile-nav-inner {
  display: flex;
  justify-content: space-around;
}

.mobile-nav-link {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  font-size: 0.65rem;
  color: var(--text-muted);
  cursor: pointer;
  padding: var(--space-sm);
  border-radius: var(--radius-sm);
  background: none;
  border: none;
  font-family: var(--font-sans);
  transition: color 0.15s ease;
}

.mobile-nav-link.active { color: var(--accent-light); }
.mobile-nav-link span:first-child { font-size: 1.4rem; }
#site-footer a:hover { color: #c084fc !important; }