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

:root {
  --bg:      #f0f4f8;
  --surface: #ffffff;
  --border:  #e2e8f0;
  --text:    #0f172a;
  --text2:   #64748b;
  --accent:  #2563eb;
  --good:    #16a34a;
  --bad:     #dc2626;
  --good-bg: #f0fdf4;
  --bad-bg:  #fef2f2;
  --radius:  14px;
  --shadow:  0 2px 12px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.12);
}

.dark {
  --bg:      #111827;
  --surface: #1f2937;
  --border:  #374151;
  --text:    #ffffff;
  --text2:   #9ca3af;
  --accent:  #3b82f6;
  --good:    #22c55e;
  --bad:     #ef4444;
  --good-bg: rgba(34, 197, 94, 0.15);
  --bad-bg:  rgba(239, 68, 68, 0.15);
}

html, body {
  -webkit-tap-highlight-color: transparent;
  user-select: none;
}

#app {
  max-width: 780px;
  margin: 0 auto;
  padding: 16px 16px 40px;
  min-height: 100%;
  display: flex;
  flex-direction: column;
}

.hidden { display: none !important; }

/* ---------- HUD ---------- */
#hud {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 12px;
}
.hud-left, .hud-right { display: flex; gap: 8px; align-items: center; }

.pill {
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  padding: 7px 14px;
  border-radius: 50px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text2);
  letter-spacing: 0.3px;
}
.pill span { color: var(--accent); font-weight: 700; }

.mini-btn {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text2);
  padding: 7px 14px;
  border-radius: 50px;
  font: inherit;
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  box-shadow: var(--shadow);
  transition: all 0.15s;
}
.mini-btn:hover { background: #fee2e2; border-color: #fca5a5; color: var(--bad); }

/* ---------- Timer bar ---------- */
#timerbar {
  height: 7px;
  background: var(--border);
  border-radius: 99px;
  overflow: hidden;
  margin-bottom: 18px;
  box-shadow: inset 0 1px 2px rgba(0,0,0,0.06);
}
#timerfill {
  height: 100%;
  width: 100%;
  background: linear-gradient(90deg, var(--accent), #818cf8);
  transition: width 0.1s linear;
  border-radius: 99px;
}
#timerfill.low { background: linear-gradient(90deg, var(--bad), #f97316); }

/* ---------- Play area ---------- */
#play {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
}

#logo-card {
  width: 100%;
  max-width: 420px;
  background: var(--surface);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-lg);
  padding: 30px 24px 20px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
  border-bottom: 6px solid var(--border);
  transition: border-bottom-color 0.3s;
}

/* Logo image area */
#logo {
  width: 180px;
  height: 180px;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}
#logo img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  border-radius: 10px;
  display: block;
}
#logo .logo-spinner {
  width: 42px;
  height: 42px;
  border: 4px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.75s linear infinite;
  position: absolute;
}
@keyframes spin { to { transform: rotate(360deg); } }

#logo .logo-fallback {
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 70px;
  font-weight: 900;
  border-radius: 12px;
  color: #fff;
}

#category {
  font-size: 11px;
  letter-spacing: 2.5px;
  text-transform: uppercase;
  color: var(--text2);
  font-weight: 600;
  background: var(--bg);
  padding: 4px 12px;
  border-radius: 50px;
  border: 1px solid var(--border);
}

/* ---------- Options ---------- */
#options {
  width: 100%;
  max-width: 480px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.opt {
  background: var(--surface);
  border: 1.5px solid var(--border);
  color: var(--text);
  padding: 16px 14px;
  border-radius: 12px;
  font: inherit;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  box-shadow: var(--shadow);
  transition: all 0.12s;
  text-align: center;
}
.opt:hover:not(:disabled) {
  border-color: var(--accent);
  background: #eef2ff;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(79,70,229,0.15);
}
.opt:disabled { cursor: default; }
.opt.correct {
  background: var(--good-bg);
  border-color: var(--good);
  color: var(--good);
}
.opt.wrong {
  background: var(--bad-bg);
  border-color: var(--bad);
  color: var(--bad);
}
.opt.dim {
  opacity: 0.4;
  background: var(--bg);
}

#feedback {
  font-size: 17px;
  font-weight: 700;
  min-height: 28px;
  text-align: center;
  padding: 0 12px;
}
#feedback.good { color: var(--good); }
#feedback.bad  { color: var(--bad); }

/* ---------- Screens ---------- */
.screen {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  gap: 16px;
  padding: 24px 0;
}

.title {
  font-size: clamp(36px, 9vw, 68px);
  font-weight: 800;
  letter-spacing: -1px;
  color: var(--accent);
}
.tag {
  color: var(--text2);
  font-size: 16px;
}

/* Start screen card */
.start-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  padding: 32px 36px;
  width: 100%;
  max-width: 520px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
}

.diff-label {
  color: var(--text2);
  letter-spacing: 2.5px;
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
}
.diff-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
  width: 100%;
}
.diff-btn {
  display: flex;
  flex-direction: column;
  gap: 4px;
  background: var(--bg);
  border: 2px solid var(--border);
  color: var(--text);
  padding: 16px 22px;
  border-radius: 12px;
  cursor: pointer;
  flex: 1;
  min-width: 140px;
  transition: all 0.14s;
}
.diff-btn b { font-size: 16px; letter-spacing: 0.5px; color: var(--text); }
.diff-btn span { font-size: 12px; color: var(--text2); }
.diff-btn:hover {
  border-color: var(--accent);
  background: #eef2ff;
  transform: translateY(-2px);
}

.best-row {
  font-size: 15px;
  color: var(--text2);
}
.best-row span { color: var(--accent); font-weight: 700; }

.disclaimer {
  color: var(--text2);
  font-size: 11px;
  line-height: 1.6;
  max-width: 460px;
  border-top: 1px solid var(--border);
  padding-top: 14px;
}

/* End screen */
.end-stats {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  justify-content: center;
}
.end-stat {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  box-shadow: var(--shadow);
  padding: 16px 24px;
  font-size: 13px;
  color: var(--text2);
  font-weight: 600;
}
.end-stat span {
  display: block;
  color: var(--accent);
  font-weight: 800;
  font-size: 26px;
  margin-top: 4px;
}
.end-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: center;
  margin-top: 8px;
}

.big-btn {
  background: var(--accent);
  color: #fff;
  border: none;
  padding: 14px 32px;
  border-radius: 10px;
  font: inherit;
  font-size: 16px;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 4px 16px rgba(79,70,229,0.35);
  transition: all 0.14s;
}
.big-btn:hover { background: #4338ca; transform: translateY(-2px); }
.big-btn.ghost {
  background: var(--surface);
  color: var(--text2);
  border: 1.5px solid var(--border);
  box-shadow: var(--shadow);
}
.big-btn.ghost:hover { border-color: var(--accent); color: var(--accent); background: #eef2ff; }

/* ---------- Toast ---------- */
#toast {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--text);
  color: #fff;
  padding: 10px 20px;
  border-radius: 99px;
  font-size: 14px;
  font-weight: 500;
  z-index: 40;
  box-shadow: 0 4px 24px rgba(0,0,0,0.2);
  animation: toastIn 0.2s ease;
  white-space: nowrap;
}
@keyframes toastIn { from { opacity:0; transform:translate(-50%,10px); } to { opacity:1; transform:translate(-50%,0); } }

/* ---------- Responsive ---------- */
@media (max-width: 520px) {
  #options { grid-template-columns: 1fr; }
  #logo { width: 150px; height: 150px; }
  .start-card { padding: 24px 20px; }
  .diff-btn { min-width: 120px; padding: 14px 16px; }
}

/* ---------- Round count buttons ---------- */
.round-cnt-btn {
  flex: 1;
  padding: 10px 16px;
  border-radius: 10px;
  font-size: 14px;
  font-weight: 700;
  border: 1.5px solid var(--border);
  background: var(--surface);
  color: var(--text2);
  cursor: pointer;
  transition: all 0.14s;
  text-align: center;
}
.round-cnt-btn:hover {
  border-color: var(--accent);
  background: #eff6ff;
  color: var(--accent);
}
.dark .round-cnt-btn:hover {
  background: rgba(30, 58, 138, 0.2);
}
.round-cnt-btn.active-cnt {
  border-color: var(--accent);
  background: #2563eb;
  color: #ffffff;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.15);
}
.dark .round-cnt-btn.active-cnt {
  border-color: #3b82f6;
  background: #3b82f6;
  color: #ffffff;
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}