:root {
  --bg: #0f172a;
  --panel: #111827;
  --text: #e5e7eb;
  --muted: #94a3b8;
  --accent: #22c55e;
  --accent-2: #38bdf8;
  --danger: #ef4444;
  --btn: #1f2937;
  --btn-hover: #334155;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Apple Color Emoji", "Segoe UI Emoji";
  background: radial-gradient(1200px 800px at 70% -10%, #0b1220, var(--bg));
  color: var(--text);
}

.app {
  max-width: 720px;
  margin: 0 auto;
  padding: 24px clamp(16px, 4vw, 32px);
  display: grid;
  gap: 20px;
}

.app__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand { display: inline-flex; align-items: center; gap: 10px; }
.brand__icon {
  width: clamp(28px, 6vw, 40px);
  height: clamp(28px, 6vw, 40px);
  object-fit: cover;
  border-radius: 10px;
  box-shadow: 0 2px 10px rgba(0,0,0,0.35);
  background: #0b1324;
}

h1 {
  font-size: clamp(20px, 4vw, 28px);
  margin: 0;
}

.mode {
  display: inline-flex;
  gap: 8px;
  align-items: center;
  background: var(--panel);
  border-radius: 10px;
  padding: 8px 12px;
}

select {
  appearance: none;
  background: var(--btn);
  color: var(--text);
  border: 1px solid #1f2937;
  border-radius: 8px;
  padding: 8px 28px 8px 10px;
}

.display {
  background: linear-gradient(180deg, #0b1324, #0a1020);
  border: 1px solid #0b1220;
  border-radius: 16px;
  padding: clamp(24px, 5vw, 40px);
  text-align: center;
  box-shadow: inset 0 0 0 1px rgba(255,255,255,0.03), 0 20px 60px rgba(0,0,0,0.35);
}

#display {
  font-variant-numeric: tabular-nums;
  letter-spacing: 1px;
  font-weight: 700;
  font-size: clamp(40px, 10vw, 80px);
  color: #eaf5ff;
  text-shadow: 0 0 18px rgba(56, 189, 248, 0.25);
}

.inputs {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.input-group {
  display: grid;
  gap: 6px;
}

label { color: var(--muted); font-size: 14px; }

input[type="number"] {
  appearance: textfield;
  background: var(--panel);
  color: var(--text);
  border: 1px solid #1f2937;
  border-radius: 12px;
  padding: 12px 14px;
  font-size: 18px;
}
input[type="number"]::-webkit-outer-spin-button,
input[type="number"]::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.controls {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
}

.btn {
  padding: 12px 14px;
  border-radius: 12px;
  border: 1px solid #1f2937;
  background: var(--btn);
  color: var(--text);
  cursor: pointer;
  transition: transform 0.04s ease, background 0.15s ease;
}
.btn:hover { background: var(--btn-hover); }
.btn:active { transform: translateY(1px); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
.btn.primary { background: linear-gradient(180deg, var(--accent-2), #0ea5e9); border-color: #0ea5e9; color: #05253a; font-weight: 700; }
.btn.primary:hover { filter: brightness(1.05); }
.btn.danger { background: linear-gradient(180deg, #ef4444, #dc2626); border-color: #dc2626; color: #3b0a0a; }

.laps {
  background: var(--panel);
  border-radius: 12px;
  padding: 12px;
}
.laps h2 { margin: 0 0 8px; font-size: 16px; color: var(--muted); }
.laps ol {
  margin: 0;
  padding-left: 20px;
  display: grid;
  gap: 6px;
}

.app__footer { color: var(--muted); text-align: center; }

@media (max-width: 520px) {
  .controls { grid-template-columns: repeat(2, 1fr); }
}