@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap');

:root {
  --body-surface-area-calculator-teal: #0D9488;
  --body-surface-area-calculator-teal-light: #14B8A6;
  --body-surface-area-calculator-teal-dark: #0F766E;
  --body-surface-area-calculator-navy: #0F172A;
  --body-surface-area-calculator-navy-mid: #1E293B;
  --body-surface-area-calculator-white: #FFFFFF;
  --body-surface-area-calculator-gray: #F1F5F9;
  --body-surface-area-calculator-gray-mid: #E2E8F0;
  --body-surface-area-calculator-text: #0F172A;
  --body-surface-area-calculator-text-muted: #64748B;
  --body-surface-area-calculator-red: #DC2626;
  --body-surface-area-calculator-amber: #D97706;
  --body-surface-area-calculator-green: #16A34A;
}

.body-surface-area-calculator-wrap * { box-sizing: border-box; }

.body-surface-area-calculator-wrap {
  font-family: 'Inter', sans-serif;
  max-width: 1100px;
  margin: 0 auto;
  padding: 20px;
  color: var(--body-surface-area-calculator-text);
}

/* Header */
.body-surface-area-calculator-header {
  background: linear-gradient(135deg, var(--body-surface-area-calculator-navy) 0%, var(--body-surface-area-calculator-navy-mid) 100%);
  color: var(--body-surface-area-calculator-white);
  padding: 40px;
  border-radius: 16px;
  text-align: center;
  margin-bottom: 20px;
}
.body-surface-area-calculator-header-icon { font-size: 48px; margin-bottom: 12px; }
.body-surface-area-calculator-header h2 { font-size: 30px; font-weight: 800; margin: 0 0 8px; }
.body-surface-area-calculator-header p { font-size: 15px; opacity: 0.7; margin: 0; }

.body-surface-area-calculator-hint { margin: 0 0 14px; font-size: 12.5px; color: var(--body-surface-area-calculator-text-muted); line-height: 1.5; }

/* History toggle */
.body-surface-area-calculator-history-toggle-btn {
  display: block;
  width: 100%;
  padding: 11px 14px;
  background: var(--body-surface-area-calculator-white);
  color: var(--body-surface-area-calculator-text-muted);
  border: 1.5px solid var(--body-surface-area-calculator-gray-mid);
  border-radius: 10px;
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  font-family: inherit;
  margin-bottom: 18px;
}
.body-surface-area-calculator-history-toggle-btn:hover { border-color: var(--body-surface-area-calculator-teal); color: var(--body-surface-area-calculator-navy); background: var(--body-surface-area-calculator-gray); }
.body-surface-area-calculator-history-panel { margin-bottom: 20px; background: var(--body-surface-area-calculator-gray); border: 1px solid var(--body-surface-area-calculator-gray-mid); border-radius: 16px; padding: 20px 20px 22px; }
.body-surface-area-calculator-history-head { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 10px; margin-bottom: 14px; }
.body-surface-area-calculator-history-title { margin: 0; font-size: 15px; color: var(--body-surface-area-calculator-navy); font-weight: 800; }
.body-surface-area-calculator-history-head-actions { display: flex; gap: 8px; }
.body-surface-area-calculator-history-list { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 10px; }
.body-surface-area-calculator-history-item {
  display: block;
  width: 100%;
  text-align: left;
  background: var(--body-surface-area-calculator-white);
  border: 1px solid var(--body-surface-area-calculator-gray-mid);
  border-radius: 10px;
  padding: 12px 14px;
  cursor: default;
  color: var(--body-surface-area-calculator-text);
  font-family: inherit;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}
.body-surface-area-calculator-history-item:hover { border-color: var(--body-surface-area-calculator-teal); box-shadow: 0 4px 12px rgba(13, 148, 136, 0.15); }
.body-surface-area-calculator-history-item-top { display: flex; justify-content: space-between; gap: 10px; font-size: 11px; color: var(--body-surface-area-calculator-text-muted); margin-bottom: 4px; }
.body-surface-area-calculator-history-item-type { font-weight: 700; color: var(--body-surface-area-calculator-teal-dark); }
.body-surface-area-calculator-history-item-summary { font-size: 12.5px; color: var(--body-surface-area-calculator-text-muted); margin-bottom: 3px; }
.body-surface-area-calculator-history-item-result { font-size: 14px; font-weight: 800; color: var(--body-surface-area-calculator-navy); }
.body-surface-area-calculator-history-empty { margin: 6px 0 0; font-size: 13px; color: var(--body-surface-area-calculator-text-muted); text-align: center; }

/* Tabs */
.body-surface-area-calculator-tab-row {
  display: flex;
  gap: 8px;
  background: var(--body-surface-area-calculator-gray);
  padding: 8px;
  border-radius: 12px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}
.body-surface-area-calculator-tab-btn {
  flex: 1 1 140px;
  padding: 10px 12px;
  border: none;
  background: transparent;
  border-radius: 8px;
  font-family: inherit;
  font-size: 14px;
  font-weight: 600;
  color: var(--body-surface-area-calculator-text-muted);
  cursor: pointer;
  transition: background .15s ease, color .15s ease;
}
.body-surface-area-calculator-tab-btn:hover { background: rgba(15, 23, 42, .06); }
.body-surface-area-calculator-tab-btn--active { background: var(--body-surface-area-calculator-teal); color: #fff; }
.body-surface-area-calculator-tab-btn--active:hover { background: var(--body-surface-area-calculator-teal); }

.body-surface-area-calculator-tab-panel { display: none; }
.body-surface-area-calculator-tab-panel--active { display: block; }

/* Main Grid */
.body-surface-area-calculator-main-grid { display: grid; grid-template-columns: 380px 1fr; gap: 24px; align-items: start; }
@media (max-width: 900px) { .body-surface-area-calculator-main-grid { grid-template-columns: 1fr; } }

/* Inputs Panel */
.body-surface-area-calculator-inputs-panel {
  background: var(--body-surface-area-calculator-white);
  border: 1px solid var(--body-surface-area-calculator-gray-mid);
  border-radius: 16px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.body-surface-area-calculator-field label { display: block; font-size: 12.5px; font-weight: 600; color: var(--body-surface-area-calculator-navy); margin-bottom: 6px; }
/* Bare `.field { flex: 1 1 180px; }` stretches a lone flex-column child to
   fill remaining vertical space - default to flex:0 1 auto/min-width:0 and
   only opt into flex:1 1 180px when scoped inside a field-row. */
.body-surface-area-calculator-field { flex: 0 1 auto; min-width: 0; }
.body-surface-area-calculator-field-row > .body-surface-area-calculator-field { flex: 1 1 180px; }
.body-surface-area-calculator-field-row { display: flex; gap: 14px; margin-bottom: 16px; flex-wrap: wrap; }
.body-surface-area-calculator-field-btn { display: flex; align-items: flex-end; }

.body-surface-area-calculator-select, .body-surface-area-calculator-input {
  width: 100%;
  border: 1.5px solid var(--body-surface-area-calculator-gray-mid);
  border-radius: 10px;
  padding: 10px 12px;
  font-size: 14.5px;
  font-family: inherit;
  color: var(--body-surface-area-calculator-text);
  background: var(--body-surface-area-calculator-white);
  transition: border-color .15s ease;
  margin-bottom: 16px;
}
.body-surface-area-calculator-field-row .body-surface-area-calculator-select,
.body-surface-area-calculator-field-row .body-surface-area-calculator-input { margin-bottom: 0; }
.body-surface-area-calculator-select:focus, .body-surface-area-calculator-input:focus { outline: none; border-color: var(--body-surface-area-calculator-teal); }

.body-surface-area-calculator-input-wrap {
  display: flex;
  align-items: center;
  border: 2px solid var(--body-surface-area-calculator-gray-mid);
  border-radius: 10px;
  overflow: hidden;
  transition: border-color 0.2s;
  margin-bottom: 16px;
}
.body-surface-area-calculator-input-wrap:focus-within { border-color: var(--body-surface-area-calculator-teal); }
.body-surface-area-calculator-prefix { background: var(--body-surface-area-calculator-gray); padding: 10px 14px; font-weight: 700; color: var(--body-surface-area-calculator-teal-dark); font-size: 15px; white-space: nowrap; }
.body-surface-area-calculator-input-inner { border: none; outline: none; padding: 10px 14px; font-size: 15px; font-weight: 600; width: 100%; color: var(--body-surface-area-calculator-navy); font-family: inherit; }

.body-surface-area-calculator-checkbox-label { display: flex; align-items: flex-start; gap: 10px; font-size: 13px; font-weight: 600; line-height: 1.5; color: var(--body-surface-area-calculator-navy); cursor: pointer; margin-bottom: 10px; }
.body-surface-area-calculator-checkbox-label input { accent-color: var(--body-surface-area-calculator-teal); width: 16px; height: 16px; flex: 0 0 auto; margin-top: 2px; }

.body-surface-area-calculator-hint-box { font-size: 12px; color: var(--body-surface-area-calculator-text-muted); background: var(--body-surface-area-calculator-gray); border-radius: 8px; padding: 10px 12px; margin: -4px 0 16px; line-height: 1.5; }

.body-surface-area-calculator-unit-toggle { display: flex; gap: 6px; margin-bottom: 16px; }
.body-surface-area-calculator-unit-btn {
  flex: 1;
  padding: 8px 10px;
  border: 1.5px solid var(--body-surface-area-calculator-gray-mid);
  background: var(--body-surface-area-calculator-white);
  border-radius: 8px;
  font-family: inherit;
  font-size: 12.5px;
  font-weight: 700;
  color: var(--body-surface-area-calculator-text-muted);
  cursor: pointer;
}
.body-surface-area-calculator-unit-btn--active { background: var(--body-surface-area-calculator-teal); border-color: var(--body-surface-area-calculator-teal); color: #fff; }

/* Calc button */
.body-surface-area-calculator-calc-btn {
  background: var(--body-surface-area-calculator-teal);
  color: var(--body-surface-area-calculator-white);
  border: none;
  padding: 15px;
  border-radius: 12px;
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
  width: 100%;
  transition: background 0.2s;
  letter-spacing: 0.3px;
  font-family: inherit;
  margin-top: 6px;
}
.body-surface-area-calculator-calc-btn:hover { background: var(--body-surface-area-calculator-teal-dark); }

.body-surface-area-calculator-btn-ghost {
  background: var(--body-surface-area-calculator-teal);
  color: var(--body-surface-area-calculator-white);
  border: none;
  border-radius: 8px;
  padding: 10px 16px;
  font-size: 13px;
  font-weight: 600;
  font-family: inherit;
  cursor: pointer;
  white-space: nowrap;
}
.body-surface-area-calculator-btn-ghost:hover { background: var(--body-surface-area-calculator-teal-dark); }
.body-surface-area-calculator-btn-ghost--small { padding: 7px 12px; font-size: 11.5px; }
.body-surface-area-calculator-btn-ghost--muted { background: var(--body-surface-area-calculator-white); color: var(--body-surface-area-calculator-text-muted); border: 1.5px solid var(--body-surface-area-calculator-gray-mid); }
.body-surface-area-calculator-btn-ghost--muted:hover { color: var(--body-surface-area-calculator-red); border-color: var(--body-surface-area-calculator-red); background: var(--body-surface-area-calculator-white); }

/* Results panel */
.body-surface-area-calculator-results-panel { display: flex; flex-direction: column; gap: 18px; }

.body-surface-area-calculator-hero-card {
  background: linear-gradient(135deg, var(--body-surface-area-calculator-navy) 0%, var(--body-surface-area-calculator-navy-mid) 100%);
  color: var(--body-surface-area-calculator-white);
  padding: 32px;
  border-radius: 16px;
  text-align: center;
}
.body-surface-area-calculator-hero-label { font-size: 13px; opacity: 0.7; margin-bottom: 8px; text-transform: uppercase; letter-spacing: 0.08em; }
.body-surface-area-calculator-hero-amount { font-size: 42px; font-weight: 800; color: var(--body-surface-area-calculator-teal-light); margin-bottom: 8px; word-break: break-word; }
.body-surface-area-calculator-hero-sub { font-size: 14px; opacity: 0.85; }
.body-surface-area-calculator-hero-sub--good { color: #4ADE80; opacity: 1; font-weight: 700; }
.body-surface-area-calculator-hero-sub--warn { color: #FBBF24; opacity: 1; font-weight: 700; }

/* Stats grid - explicit minmax(0,1fr) tracks + min-width:0 so cells shrink
   below an <input>/value's minimum content width in narrow (~380px) panels
   instead of overflowing (bare 1fr tracks don't shrink for this). */
.body-surface-area-calculator-stats-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.body-surface-area-calculator-stats-grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
@media (max-width: 640px) {
  .body-surface-area-calculator-stats-grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
.body-surface-area-calculator-stat-card { background: var(--body-surface-area-calculator-white); border: 1px solid var(--body-surface-area-calculator-gray-mid); border-radius: 12px; padding: 14px; text-align: center; min-width: 0; }
.body-surface-area-calculator-stat-label { font-size: 10.5px; color: var(--body-surface-area-calculator-text-muted); margin-bottom: 4px; text-transform: uppercase; letter-spacing: 0.03em; }
.body-surface-area-calculator-stat-val { font-size: 15px; font-weight: 800; color: var(--body-surface-area-calculator-navy); word-break: break-word; }
.body-surface-area-calculator-stat-val--good { color: var(--body-surface-area-calculator-green); }
.body-surface-area-calculator-stat-val--warn { color: var(--body-surface-area-calculator-amber); }

/* Spread callout - distinct highlighted stat, not buried in the table */
.body-surface-area-calculator-spread-card {
  background: linear-gradient(135deg, #fffbeb 0%, #fef3c7 100%);
  border: 1.5px solid #fcd34d;
  border-radius: 14px;
  padding: 16px 20px;
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}
.body-surface-area-calculator-spread-icon { font-size: 28px; flex: 0 0 auto; }
.body-surface-area-calculator-spread-text { flex: 1 1 200px; min-width: 0; }
.body-surface-area-calculator-spread-label { font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.04em; color: #92400e; margin-bottom: 3px; }
.body-surface-area-calculator-spread-val { font-size: 20px; font-weight: 800; color: #92400e; }

/* BMI card */
.body-surface-area-calculator-bmi-card {
  background: var(--body-surface-area-calculator-white);
  border: 1px solid var(--body-surface-area-calculator-gray-mid);
  border-radius: 14px;
  padding: 16px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  flex-wrap: wrap;
}
.body-surface-area-calculator-bmi-label { font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.04em; color: var(--body-surface-area-calculator-text-muted); margin-bottom: 3px; }
.body-surface-area-calculator-bmi-val { font-size: 22px; font-weight: 800; color: var(--body-surface-area-calculator-navy); }
.body-surface-area-calculator-bmi-badge { font-size: 12px; font-weight: 700; padding: 6px 12px; border-radius: 999px; white-space: nowrap; }
.body-surface-area-calculator-bmi-badge--under { background: #dbeafe; color: #1d4ed8; }
.body-surface-area-calculator-bmi-badge--normal { background: #dcfce7; color: #15803d; }
.body-surface-area-calculator-bmi-badge--over { background: #fef3c7; color: #b45309; }
.body-surface-area-calculator-bmi-badge--obese { background: #fee2e2; color: #b91c1c; }

/* Guidance note */
.body-surface-area-calculator-guidance-card {
  background: #eff6ff;
  border: 1.5px solid #bfdbfe;
  border-radius: 14px;
  padding: 14px 18px;
  font-size: 13px;
  line-height: 1.6;
  color: #1e3a5f;
}
.body-surface-area-calculator-guidance-label { font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.04em; color: #1d4ed8; margin-bottom: 6px; }

/* Chart / table cards */
.body-surface-area-calculator-chart-card, .body-surface-area-calculator-table-card {
  background: var(--body-surface-area-calculator-white);
  border: 1px solid var(--body-surface-area-calculator-gray-mid);
  border-radius: 16px;
  padding: 18px;
}
.body-surface-area-calculator-chart-title { font-size: 12.5px; font-weight: 700; color: var(--body-surface-area-calculator-navy); text-transform: uppercase; letter-spacing: 0.04em; margin-bottom: 12px; }

/* Bar chart (8 formulas, single color comparison) */
.body-surface-area-calculator-bar-chart-wrap { position: relative; overflow-x: auto; }
.body-surface-area-calculator-bar-chart { width: 100%; height: 240px; display: block; }
.body-surface-area-calculator-bar-chart-legend { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 10px; font-size: 11.5px; color: var(--body-surface-area-calculator-text-muted); }
.body-surface-area-calculator-bar-chart-legend-item { display: flex; align-items: center; gap: 6px; }
.body-surface-area-calculator-bar-chart-legend-swatch { width: 10px; height: 10px; border-radius: 3px; display: inline-block; flex: 0 0 auto; }

.body-surface-area-calculator-chart-tooltip {
  position: absolute;
  z-index: 5;
  pointer-events: none;
  background: var(--body-surface-area-calculator-navy);
  color: var(--body-surface-area-calculator-white);
  border-radius: 8px;
  padding: 8px 10px;
  font-size: 12px;
  line-height: 1.5;
  box-shadow: 0 8px 20px rgba(15, 23, 42, 0.25);
  white-space: nowrap;
}

/* Table */
.body-surface-area-calculator-table-wrap {
  background: var(--body-surface-area-calculator-white);
  border: 1px solid var(--body-surface-area-calculator-gray-mid);
  border-radius: 12px;
  overflow: hidden;
  max-height: 360px;
  overflow-y: auto;
}
.body-surface-area-calculator-table { width: 100%; border-collapse: collapse; font-size: 13px; }
.body-surface-area-calculator-table th {
  position: sticky;
  top: 0;
  background: var(--body-surface-area-calculator-navy);
  color: white;
  text-align: right;
  padding: 10px 14px;
  font-weight: 600;
  font-size: 11.5px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}
.body-surface-area-calculator-table th:first-child, .body-surface-area-calculator-table td:first-child { text-align: left; }
.body-surface-area-calculator-table td {
  padding: 9px 14px;
  text-align: right;
  border-bottom: 1px solid var(--body-surface-area-calculator-gray-mid);
  color: var(--body-surface-area-calculator-text);
}
.body-surface-area-calculator-table td:first-child { text-align: left; }
.body-surface-area-calculator-table tr:nth-child(even) { background: var(--body-surface-area-calculator-gray); }
.body-surface-area-calculator-table-row--hero { background: #f0fdfa !important; font-weight: 700; color: var(--body-surface-area-calculator-teal-dark); }

/* Export */
.body-surface-area-calculator-export-row { display: flex; gap: 10px; flex-wrap: wrap; }
.body-surface-area-calculator-export-btn {
  flex: 1;
  min-width: 100px;
  background: var(--body-surface-area-calculator-white);
  border: 1.5px solid var(--body-surface-area-calculator-gray-mid);
  border-radius: 10px;
  padding: 10px 14px;
  font-size: 13.5px;
  font-weight: 600;
  font-family: inherit;
  color: var(--body-surface-area-calculator-navy);
  cursor: pointer;
  transition: border-color .15s ease, background .15s ease;
}
.body-surface-area-calculator-export-btn:hover { border-color: var(--body-surface-area-calculator-teal); background: var(--body-surface-area-calculator-gray); }

.body-surface-area-calculator-disclaimer { margin-top: 4px; font-size: 11.5px; color: var(--body-surface-area-calculator-text-muted); line-height: 1.6; }

/* Standard disclaimer box (gray) */
.body-surface-area-calculator-disclaimer-box {
  background: var(--body-surface-area-calculator-gray);
  border: 1px solid var(--body-surface-area-calculator-gray-mid);
  border-radius: 12px;
  padding: 14px 16px;
  font-size: 12px;
  line-height: 1.6;
  color: var(--body-surface-area-calculator-text-muted);
}

/* Prominent warning-styled disclaimer box (Tab 2: dosing) - visually
   distinct red/amber warning box, NOT the standard gray disclaimer. */
.body-surface-area-calculator-warning-box {
  background: #fef2f2;
  border: 2px solid var(--body-surface-area-calculator-red);
  border-radius: 14px;
  padding: 16px 18px;
  display: flex;
  gap: 12px;
  align-items: flex-start;
}
.body-surface-area-calculator-warning-icon { font-size: 26px; flex: 0 0 auto; line-height: 1; }
.body-surface-area-calculator-warning-text { font-size: 13px; line-height: 1.6; color: #991b1b; font-weight: 600; }
.body-surface-area-calculator-warning-text strong { color: #7f1d1d; }

/* BSA source card (Tab 2 / Tab 3) */
.body-surface-area-calculator-bsa-source-card {
  background: #f0fdfa;
  border: 1.5px solid var(--body-surface-area-calculator-teal);
  border-radius: 14px;
  padding: 14px 18px;
}
.body-surface-area-calculator-bsa-source-title { font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.04em; color: var(--body-surface-area-calculator-teal-dark); margin-bottom: 8px; }
.body-surface-area-calculator-bsa-source-row { display: flex; justify-content: space-between; align-items: center; gap: 10px; flex-wrap: wrap; font-size: 13px; color: var(--body-surface-area-calculator-navy); }

.body-surface-area-calculator-radio-row { display: flex; gap: 16px; margin-bottom: 16px; flex-wrap: wrap; }
.body-surface-area-calculator-radio-label { display: flex; align-items: center; gap: 6px; font-size: 13px; font-weight: 600; color: var(--body-surface-area-calculator-navy); cursor: pointer; }
.body-surface-area-calculator-radio-label input { accent-color: var(--body-surface-area-calculator-teal); }

@media (max-width: 640px) {
  .body-surface-area-calculator-header { padding: 28px 20px; }
  .body-surface-area-calculator-header h2 { font-size: 24px; }
  .body-surface-area-calculator-hero-amount { font-size: 30px; }
  .body-surface-area-calculator-export-row { flex-direction: column; }
  .body-surface-area-calculator-stats-grid { grid-template-columns: minmax(0, 1fr); }
}