/* ── Reset & Base ─────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg:        #0f1117;
  --bg2:       #181c27;
  --bg3:       #1e2333;
  --border:    #2a3050;
  --blue:      #4da6ff;
  --blue-dim:  #2d6fad;
  --blue-glow: rgba(77,166,255,0.18);
  --text:      #e8eaf0;
  --text-dim:  #8c92a8;
  --good:      #4cdb8a;
  --warn:      #f5a623;
  --bad:       #f55b5b;
  --radius:    12px;
  --radius-sm: 8px;
}

html { font-size: 16px; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Segoe UI', system-ui, sans-serif;
  min-height: 100vh;
  line-height: 1.6;
}

/* ── Layout ───────────────────────────────────────────────────── */
.app-container {
  max-width: 960px;
  margin: 0 auto;
  padding: 24px 16px 64px;
}

header {
  margin-bottom: 32px;
}
.header-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
.site-title {
  display: flex;
  align-items: center;
  gap: 12px;
}
.site-logo {
  height: 44px;
  width: auto;
  object-fit: contain;
}
header h1 {
  font-size: 1.7rem;
  font-weight: 700;
  background: linear-gradient(135deg, #ffffff 40%, var(--blue));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.5px;
  white-space: nowrap;
}

/* ── Tab Navigation ───────────────────────────────────────────── */
.tab-nav {
  display: inline-flex;
  background: var(--bg3);
  border-radius: 50px;
  padding: 4px;
  gap: 4px;
  border: 1px solid var(--border);
}
.tab-btn {
  background: none;
  border: none;
  color: var(--text-dim);
  padding: 10px 32px;
  border-radius: 50px;
  cursor: pointer;
  font-size: 0.95rem;
  font-weight: 500;
  transition: all 0.2s;
}
.tab-btn:hover { color: var(--text); }
.tab-btn.active {
  background: var(--blue);
  color: #fff;
  box-shadow: 0 2px 12px var(--blue-glow);
}

/* ── Tab Content ──────────────────────────────────────────────── */
.tab-content { display: none; }
.tab-content.active { display: block; }

/* ── Selector Row ─────────────────────────────────────────────── */
.selector-row {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}
.selector-row label {
  font-weight: 600;
  color: var(--text-dim);
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  white-space: nowrap;
}
select {
  flex: 1;
  min-width: 240px;
  background: var(--bg3);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  padding: 10px 14px;
  font-size: 0.95rem;
  cursor: pointer;
  outline: none;
  transition: border-color 0.2s;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%234da6ff' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 14px center;
  padding-right: 38px;
}
select:focus { border-color: var(--blue); box-shadow: 0 0 0 3px var(--blue-glow); }
select option, select optgroup { background: var(--bg2); }

/* ── Cards ────────────────────────────────────────────────────── */
.card {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  margin-bottom: 20px;
}
.card-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--blue);
  margin-bottom: 6px;
}
.card-subtitle {
  font-size: 0.88rem;
  color: var(--text-dim);
  margin-bottom: 18px;
}

/* ── Resource Panels ──────────────────────────────────────────── */
.resource-panel .placeholder,
.calc-panel .placeholder {
  text-align: center;
  color: var(--text-dim);
  padding: 60px 20px;
  font-size: 1rem;
}

/* ── Sub-tabs (resource sex toggle) ──────────────────────────── */
.sub-tabs {
  display: flex;
  gap: 8px;
  margin-bottom: 16px;
  flex-wrap: wrap;
}
.sub-tab-btn {
  background: var(--bg3);
  border: 1px solid var(--border);
  color: var(--text-dim);
  padding: 6px 18px;
  border-radius: 50px;
  cursor: pointer;
  font-size: 0.88rem;
  transition: all 0.2s;
}
.sub-tab-btn.active {
  background: var(--blue-dim);
  border-color: var(--blue);
  color: #fff;
}

/* ── Tables ───────────────────────────────────────────────────── */
.table-wrap {
  overflow-x: auto;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  margin-bottom: 12px;
}
table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.875rem;
}
thead th {
  background: var(--bg3);
  color: var(--blue);
  font-weight: 600;
  padding: 10px 12px;
  text-align: center;
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}
thead th:first-child { text-align: left; }
tbody tr:nth-child(even) { background: rgba(255,255,255,0.025); }
tbody tr:hover { background: var(--blue-glow); }
tbody td {
  padding: 9px 12px;
  text-align: center;
  border-bottom: 1px solid rgba(42,48,80,0.5);
  color: var(--text);
}
tbody td:first-child { text-align: left; font-weight: 500; }
tbody tr:last-child td { border-bottom: none; }

.source-line {
  font-size: 0.8rem;
  color: var(--text-dim);
  margin-top: 8px;
}
.source-line a {
  color: var(--blue);
  text-decoration: none;
}
.source-line a:hover { text-decoration: underline; }

/* ── Category badges in tables ────────────────────────────────── */
.badge {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 50px;
  font-size: 0.75rem;
  font-weight: 600;
}
.badge-blue   { background: rgba(77,166,255,0.15); color: var(--blue); }
.badge-green  { background: rgba(76,219,138,0.15); color: var(--good); }
.badge-yellow { background: rgba(245,166,35,0.15); color: var(--warn); }
.badge-red    { background: rgba(245,91,91,0.15);  color: var(--bad); }

/* ── Calculator Forms ─────────────────────────────────────────── */
.calc-section { margin-bottom: 24px; }
.calc-section-title {
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-dim);
  margin-bottom: 12px;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--border);
}

.input-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 14px;
}
.input-group {
  display: flex;
  flex-direction: column;
  gap: 5px;
}
.input-group label {
  font-size: 0.82rem;
  color: var(--text-dim);
  font-weight: 500;
}
.input-group input,
.input-group select {
  min-width: unset;
  width: 100%;
  padding: 9px 12px;
  font-size: 0.92rem;
}

.calc-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--blue);
  color: #fff;
  border: none;
  border-radius: var(--radius-sm);
  padding: 11px 28px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  margin-top: 8px;
  box-shadow: 0 2px 12px var(--blue-glow);
}
.calc-btn:hover {
  background: #6db8ff;
  transform: translateY(-1px);
  box-shadow: 0 4px 20px var(--blue-glow);
}
.calc-btn:active { transform: translateY(0); }

/* ── Output Boxes ─────────────────────────────────────────────── */
.output-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 12px;
  margin-bottom: 4px;
}
.output-box {
  background: var(--bg3);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 14px 16px;
  text-align: center;
}
.output-box .out-label {
  font-size: 0.75rem;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 4px;
}
.output-box .out-value {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--blue);
}
.output-box .out-unit {
  font-size: 0.78rem;
  color: var(--text-dim);
}
.output-box.highlight {
  border-color: var(--blue);
  background: var(--blue-glow);
}

/* ── Formula display ──────────────────────────────────────────── */
.formula-block {
  background: var(--bg3);
  border-left: 3px solid var(--blue);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  padding: 14px 18px;
  margin: 12px 0;
  font-family: 'Courier New', monospace;
  font-size: 0.88rem;
  color: var(--text);
  overflow-x: auto;
}
.formula-block .formula-title {
  font-family: inherit;
  font-weight: 700;
  color: var(--blue);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  margin-bottom: 6px;
  font-style: normal;
}
.var-table { width: 100%; border-collapse: collapse; font-size: 0.82rem; margin-top: 10px; }
.var-table td { padding: 4px 8px; border-bottom: 1px solid var(--border); }
.var-table td:first-child { color: var(--blue); font-weight: 600; font-family: 'Courier New', monospace; width: 80px; }
.var-table tr:last-child td { border-bottom: none; }

.description-block {
  font-size: 0.875rem;
  color: var(--text-dim);
  line-height: 1.7;
  margin-top: 10px;
}
.description-block p { margin-bottom: 6px; }

/* ── Result table for multi-result calcs ─────────────────────── */
.result-table-wrap {
  overflow-x: auto;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  margin-bottom: 12px;
}

/* ── Percentile bar ───────────────────────────────────────────── */
.pct-bar-wrap {
  margin: 10px 0 4px;
}
.pct-bar-label {
  font-size: 0.8rem;
  color: var(--text-dim);
  margin-bottom: 4px;
  display: flex;
  justify-content: space-between;
}
.pct-bar-track {
  background: var(--bg3);
  border-radius: 50px;
  height: 10px;
  overflow: hidden;
  border: 1px solid var(--border);
}
.pct-bar-fill {
  height: 100%;
  border-radius: 50px;
  background: linear-gradient(90deg, var(--blue-dim), var(--blue));
  transition: width 0.5s ease;
}

/* ── Utility ──────────────────────────────────────────────────── */
.hidden { display: none !important; }
.mt-2 { margin-top: 8px; }
.mt-4 { margin-top: 16px; }
.text-dim { color: var(--text-dim); font-size: 0.875rem; }
.text-blue { color: var(--blue); }
.divider { border: none; border-top: 1px solid var(--border); margin: 20px 0; }

/* ── Disclaimer Footer ────────────────────────────────────────── */
.disclaimer {
  background: var(--bg2);
  border-top: 1px solid var(--border);
  margin-top: 48px;
  padding: 28px 16px;
}
.disclaimer-inner {
  max-width: 960px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.disclaimer-heading {
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--warn);
  margin-bottom: 2px;
}
.disclaimer p {
  font-size: 0.78rem;
  color: var(--text-dim);
  line-height: 1.65;
}
.disclaimer p strong {
  color: #a0a8c0;
}

/* ── Responsive ───────────────────────────────────────────────── */
@media (max-width: 600px) {
  .header-row { justify-content: center; }
  header h1 { font-size: 1.3rem; }
  .card { padding: 18px; }
  .input-grid { grid-template-columns: 1fr 1fr; }
  .output-grid { grid-template-columns: 1fr 1fr; }
}