:root {
  --bg: #f4f6f3;
  --card: #ffffff;
  --ink: #1a1a1a;
  --muted: #6b7280;
  --accent: #0b3d0b;
  --accent-ink: #ffffff;
  --border: #e3e7e0;
  --dim: #f8faf6;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.4 -apple-system, BlinkMacSystemFont, "SF Pro Text", system-ui, sans-serif;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  background: var(--accent);
  color: var(--accent-ink);
  position: sticky;
  top: 0;
  z-index: 10;
}

.topbar .brand {
  color: var(--accent-ink);
  font-weight: 700;
  text-decoration: none;
  font-size: 1.05rem;
}

.topbar nav a {
  color: var(--accent-ink);
  text-decoration: none;
  margin-left: 16px;
  opacity: 0.85;
  font-size: 0.95rem;
}

.container {
  max-width: 560px;
  margin: 0 auto;
  padding: 16px;
  padding-bottom: env(safe-area-inset-bottom, 16px);
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 18px;
  margin-bottom: 16px;
}

.card.dim { background: var(--dim); }

.card h2 { margin: 0 0 6px; font-size: 1.25rem; }
.card h3 { margin: 0 0 12px; font-size: 1.05rem; }

.meta { color: var(--muted); font-size: 0.88rem; margin: 4px 0 0; }

.index {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-top: 8px;
}
.index .label { color: var(--muted); font-size: 0.9rem; }
.index .value { font-size: 2.1rem; font-weight: 700; letter-spacing: -0.02em; }

.hero { text-align: center; padding: 28px 18px; }
.hero .label { color: var(--muted); font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.08em; }
.hero .big { font-size: 4rem; font-weight: 700; line-height: 1; margin: 8px 0; letter-spacing: -0.03em; color: var(--accent); }
.hero .sub { color: var(--muted); font-size: 0.95rem; }

.predict-form, .settings-form {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-top: 4px;
}

label {
  display: flex;
  flex-direction: column;
  gap: 6px;
  color: var(--muted);
  font-size: 0.85rem;
}

input, select {
  font: inherit;
  color: var(--ink);
  padding: 12px 12px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: #fff;
  -webkit-appearance: none;
}

input:focus, select:focus {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
}

button, .button {
  display: inline-block;
  font: inherit;
  padding: 14px 16px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: #fff;
  color: var(--ink);
  text-decoration: none;
  text-align: center;
  cursor: pointer;
}

button.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--accent-ink);
  font-weight: 600;
}

.breakdown {
  width: 100%;
  border-collapse: collapse;
}
.breakdown td {
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
  font-size: 0.95rem;
}
.breakdown td:last-child { text-align: right; font-variant-numeric: tabular-nums; font-weight: 600; }
.breakdown tr:last-child td { border-bottom: none; }

.flash {
  background: #fff7cc;
  border: 1px solid #e6d78a;
  padding: 10px 14px;
  border-radius: 10px;
  margin-bottom: 12px;
  font-size: 0.9rem;
}

.actions { margin-top: 4px; }

.index-form {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid var(--border);
}
.index-form label {
  font-size: 0.82rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
.index-row {
  display: flex;
  gap: 8px;
  margin-top: 6px;
}
.index-row input {
  flex: 1;
  font-size: 1.1rem;
  font-variant-numeric: tabular-nums;
}
.index-row button {
  white-space: nowrap;
}
.hint { margin-top: 8px; font-size: 0.82rem; }

.method h3 { margin-bottom: 4px; }

.method-step {
  padding: 14px 0;
  border-bottom: 1px solid var(--border);
}
.method-step:last-of-type { border-bottom: none; padding-bottom: 6px; }

.step-label {
  display: inline-block;
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  background: var(--dim);
  padding: 2px 8px;
  border-radius: 4px;
}
.step-title {
  font-size: 1rem;
  font-weight: 600;
  margin: 6px 0 10px;
}
.step-body { font-size: 0.92rem; }

.formula {
  background: var(--dim);
  padding: 10px 12px;
  border-radius: 8px;
  margin-bottom: 8px;
  font-size: 0.88rem;
}
.formula code {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
}

.plug-in {
  font-variant-numeric: tabular-nums;
  font-size: 0.95rem;
  padding: 6px 0;
}

.note {
  color: var(--muted);
  font-size: 0.82rem;
  margin-top: 4px;
}

.adj-row {
  display: grid;
  grid-template-columns: 84px 1fr auto;
  gap: 10px;
  align-items: center;
  padding: 8px 0;
  border-top: 1px solid var(--border);
  font-size: 0.9rem;
}
.adj-row:first-of-type { border-top: none; }
.adj-name { font-weight: 600; }
.adj-rule { color: var(--muted); font-size: 0.82rem; }
.adj-calc { font-variant-numeric: tabular-nums; white-space: nowrap; }

.method-sources {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px solid var(--border);
  font-size: 0.82rem;
  color: var(--muted);
  line-height: 1.5;
}
.method-sources a { color: var(--accent); }

@media (max-width: 420px) {
  .adj-row { grid-template-columns: 72px 1fr; }
  .adj-calc { grid-column: 2; text-align: left; margin-top: -4px; }
}

#refresh-overlay[hidden] { display: none !important; }

#refresh-overlay {
  position: fixed;
  inset: 0;
  background: rgba(11, 61, 11, 0.92);
  color: #fff;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 18px;
  z-index: 100;
  font-size: 1.05rem;
  text-align: center;
  padding: 24px;
}

#refresh-overlay small { opacity: 0.75; font-size: 0.85rem; }

.spinner {
  width: 44px;
  height: 44px;
  border: 4px solid rgba(255, 255, 255, 0.25);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.85s linear infinite;
}

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