:root {
  color-scheme: light;
  --bg: #f3f6fb;
  --card: #ffffff;
  --text: #1a1f2e;
  --muted: #63708b;
  --primary: #2e6df6;
  --primary-soft: #dfe9ff;
  --border: #d9e0ef;
  --danger: #d82a4e;
}

* {
  box-sizing: border-box;
}

body {
  font-family: "Noto Sans TC", "Segoe UI", sans-serif;
  margin: 0;
  padding: 1.25rem;
  background: radial-gradient(circle at top, #fbfdff, var(--bg));
  color: var(--text);
}

.app-shell {
  max-width: 880px;
  margin: 0 auto;
  display: grid;
  gap: 1rem;
}

.app-header {
  text-align: center;
}

h1 {
  margin: 0;
  font-size: clamp(1.6rem, 3vw, 2.1rem);
}

.subtitle {
  margin-top: 0.5rem;
  color: var(--muted);
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 1rem;
  box-shadow: 0 6px 18px rgba(24, 34, 64, 0.06);
}

.card h2 {
  margin: 0 0 0.75rem;
  font-size: 1.1rem;
}

.controls {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 0.8rem;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

label {
  color: var(--muted);
  font-size: 0.92rem;
}

.field input {
  width: 100%;
  padding: 0.65rem 0.75rem;
  border: 1px solid var(--border);
  border-radius: 9px;
  font-size: 1rem;
}

.field input:focus {
  outline: 2px solid var(--primary-soft);
  border-color: var(--primary);
}

.toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 0.9rem;
}

button {
  border: 1px solid var(--primary);
  background: var(--primary);
  color: white;
  padding: 0.55rem 0.8rem;
  border-radius: 9px;
  font-size: 0.92rem;
  cursor: pointer;
}

button#reset-btn {
  background: #fff;
  color: var(--primary);
}

.hint {
  min-height: 1.2rem;
  margin: 0.5rem 0 0;
  color: var(--muted);
  font-size: 0.9rem;
}

.headline {
  margin: 0 0 0.65rem;
  font-size: 1.15rem;
}

#p_hyper,
#p20,
#p50,
#ptarget {
  color: var(--danger);
}

.summary-grid {
  display: grid;
  grid-template-columns: minmax(180px, 1fr) 1fr;
  gap: 0.4rem 1rem;
}

.summary-grid p {
  margin: 0;
  padding: 0.2rem 0;
}

table {
  width: 100%;
  border-collapse: collapse;
}

th,
td {
  border-bottom: 1px solid var(--border);
  padding: 0.55rem;
  text-align: center;
}

th {
  background: #f7f9fe;
}

#prob-table tbody tr:nth-child(5n) td {
  color: var(--primary);
  font-weight: 700;
}

@media (max-width: 640px) {
  body { padding: 0.75rem; }
  .summary-grid {
    grid-template-columns: 1fr;
    gap: 0;
  }
}