:root {
  --bg: #141414;
  --surface: #1e1e1e;
  --surface2: #272727;
  --border: #333;
  --text: #d4d4d4;
  --text-muted: #888;
  --accent: #e8a020;
  --accent-dim: #b07818;
  --green: #56a356;
  --green-dim: #3a7a3a;
  --tab-active-bg: #1e1e1e;
  --radius: 6px;
  --gap: 14px;
}

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

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Segoe UI', system-ui, sans-serif;
  font-size: 14px;
  min-height: 100vh;
}

/* ── Header ── */
header {
  background: #0e0e0e;
  border-bottom: 2px solid var(--accent-dim);
  padding: 14px 24px;
}
header h1 {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: var(--accent);
}

/* ── Tabs ── */
#tab-bar {
  display: flex;
  gap: 2px;
  background: #0e0e0e;
  padding: 0 24px;
  border-bottom: 1px solid var(--border);
}

.tab {
  background: transparent;
  border: none;
  border-bottom: 3px solid transparent;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
  padding: 10px 16px;
  transition: color 0.15s, border-color 0.15s;
}
.tab:hover { color: var(--text); }
.tab.active {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* ── Tab content ── */
#tab-content {
  padding: 20px 24px;
  max-width: 1100px;
}

/* ── Calculator shell ── */
.calculator {
  display: grid;
  grid-template-columns: 340px 1fr;
  gap: var(--gap);
  align-items: start;
}
@media (max-width: 720px) {
  .calculator { grid-template-columns: 1fr; }
}

.calc-inputs { display: flex; flex-direction: column; gap: var(--gap); }
.calc-results { display: flex; flex-direction: column; gap: var(--gap); }

/* ── Cards ── */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
}
.card h2 {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 12px;
}

/* ── Input row / groups ── */
.input-row {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}
.input-row label, .input-solo label {
  display: flex;
  flex-direction: column;
  gap: 4px;
  font-size: 12px;
  color: var(--text-muted);
}
.input-row select,
.input-solo select {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 4px;
  color: var(--text);
  font-size: 14px;
  padding: 6px 8px;
  width: 80px;
  cursor: pointer;
  transition: border-color 0.15s;
}
.input-row select:focus,
.input-solo select:focus {
  border-color: var(--accent-dim);
  outline: none;
}

.input-row input[type="number"],
.input-solo input[type="number"] {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 4px;
  color: var(--text);
  font-size: 14px;
  padding: 6px 8px;
  width: 80px;
  transition: border-color 0.15s;
}
.input-row input[type="number"]:focus,
.input-solo input[type="number"]:focus {
  border-color: var(--accent-dim);
  outline: none;
}
.input-solo { margin-top: 10px; }
.input-solo input[type="number"] { width: 120px; }

/* ── Radio groups ── */
.radio-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.radio-group label {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  font-size: 13px;
  color: var(--text);
}
.radio-group input[type="radio"] { accent-color: var(--accent); cursor: pointer; }

/* ── Toggle (crafting method) ── */
.toggle-group {
  display: flex;
  gap: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  width: fit-content;
}
.toggle {
  background: var(--surface2);
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 13px;
  font-weight: 600;
  padding: 8px 16px;
  transition: background 0.15s, color 0.15s;
}
.toggle:hover { color: var(--text); }
.toggle.active {
  background: var(--accent-dim);
  color: #fff;
}

/* ── Helpers ── */
.hidden { display: none !important; }

.hint {
  font-size: 11px;
  color: var(--text-muted);
  margin-top: 8px;
  line-height: 1.4;
}

/* ── Results ── */
.result-empty {
  color: var(--text-muted);
  font-size: 13px;
  text-align: center;
  padding: 40px 0;
}

.block-summary {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
}
.block-item {
  background: var(--surface2);
  border-radius: 4px;
  padding: 10px 12px;
}
.block-item .bi-label {
  font-size: 11px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
.block-item .bi-value {
  font-size: 22px;
  font-weight: 700;
  color: var(--accent);
  margin-top: 2px;
}
.block-item.total .bi-value { color: var(--text); }

.capacity-row {
  display: flex;
  gap: 10px;
}
.capacity-item {
  flex: 1;
  background: var(--surface2);
  border-radius: 4px;
  padding: 10px 12px;
}
.capacity-item .ci-label {
  font-size: 11px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
.capacity-item .ci-value {
  font-size: 18px;
  font-weight: 700;
  color: var(--green);
  margin-top: 2px;
}

/* ── Material list ── */
.mat-list { display: flex; flex-direction: column; gap: 6px; }
.mat-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 7px 10px;
  background: var(--surface2);
  border-radius: 4px;
}
.mat-row:first-child { margin-top: 0; }
.mat-name { font-size: 13px; color: var(--text); }
.mat-count {
  font-size: 16px;
  font-weight: 700;
  color: var(--accent);
  font-variant-numeric: tabular-nums;
}
.mat-sub {
  font-size: 11px;
  color: var(--text-muted);
  margin-top: 2px;
}
.mat-row.ingots-row { border: 1px solid var(--accent-dim); }
.mat-row.ingots-row .mat-name { color: var(--accent); }
.mat-separator {
  height: 1px;
  background: var(--border);
  margin: 6px 0;
}

.mat-section {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  color: var(--text-muted);
  padding: 4px 2px 6px;
}
.mat-section-count {
  font-weight: 400;
  text-transform: none;
  letter-spacing: 0;
}

.group-label {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  color: var(--text-muted);
  display: block;
  margin-bottom: 6px;
}
.warn-row {
  background: #2a1f00;
  border: 1px solid #6b4700;
  border-radius: 4px;
  color: #e8a020;
  font-size: 12px;
  padding: 8px 10px;
}