:root {
  color-scheme: light;
  --bg: #f2f6fb;
  --surface: #ffffff;
  --surface-soft: #f8fafc;
  --text: #152238;
  --muted: #5d6b7d;
  --border: #dbe4ef;
  --primary: #0f4c81;
  --primary-strong: #083a66;
  --primary-soft: #e9f3ff;
  --success: #16794b;
  --success-soft: #e9f8f0;
  --warning: #946200;
  --warning-soft: #fff6d9;
  --danger: #b42318;
  --danger-soft: #fff0ef;
  --shadow: 0 18px 45px rgba(37, 59, 88, 0.10);
  --radius: 22px;
  --radius-small: 14px;
}

html[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0d1623;
  --surface: #142033;
  --surface-soft: #18273b;
  --text: #edf4fb;
  --muted: #b3c0cf;
  --border: #2d3e53;
  --primary: #74b9ff;
  --primary-strong: #9bcaff;
  --primary-soft: #183757;
  --success: #62d79b;
  --success-soft: #173b2c;
  --warning: #ffd166;
  --warning-soft: #443719;
  --danger: #ff8b82;
  --danger-soft: #451e20;
  --shadow: 0 20px 50px rgba(0, 0, 0, 0.28);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  min-width: 320px;
  background:
    radial-gradient(circle at 8% 0%, rgba(39, 128, 227, 0.10), transparent 27rem),
    radial-gradient(circle at 100% 20%, rgba(62, 185, 152, 0.08), transparent 24rem),
    var(--bg);
  color: var(--text);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.55;
}
button, input, select { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
a { color: inherit; }
.container { width: min(1180px, calc(100% - 32px)); margin-inline: auto; }
.print-only { display: none; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  border-bottom: 1px solid color-mix(in srgb, var(--border) 85%, transparent);
  background: color-mix(in srgb, var(--surface) 88%, transparent);
  backdrop-filter: blur(16px);
}
.header-inner { min-height: 72px; display: flex; align-items: center; gap: 24px; }
.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; font-size: 1.22rem; font-weight: 900; }
.brand-mark {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border-radius: 14px;
  color: #fff;
  background: linear-gradient(135deg, #1680d9, #3348b8);
  box-shadow: 0 10px 25px rgba(24, 99, 186, 0.25);
}
.main-nav { margin-left: auto; display: flex; align-items: center; gap: 18px; }
.main-nav a { color: var(--muted); text-decoration: none; font-size: 0.92rem; font-weight: 750; }
.main-nav a:hover, .main-nav a:focus-visible, .main-nav a[aria-current="page"] { color: var(--primary); }

.panel { border: 1px solid var(--border); border-radius: var(--radius); background: color-mix(in srgb, var(--surface) 97%, transparent); box-shadow: var(--shadow); }
.hero { padding: 42px 0 18px; }
.hero-grid { display: grid; grid-template-columns: minmax(0, 1.5fr) minmax(280px, 0.72fr); gap: 22px; }
.hero-main { padding: clamp(26px, 5vw, 48px); }
.hero-main h1 { margin: 18px 0 10px; font-size: clamp(2.25rem, 6vw, 4.35rem); line-height: 1.02; letter-spacing: -0.055em; }
.hero-lead { max-width: 820px; margin: 0; color: var(--muted); font-size: clamp(1.04rem, 2vw, 1.3rem); }
.badge, .public-label, .module-number, .result-kicker {
  display: inline-flex;
  align-items: center;
  width: fit-content;
  border-radius: 999px;
  font-size: 0.78rem;
  font-weight: 850;
  letter-spacing: 0.035em;
}
.badge { padding: 8px 12px; color: var(--primary); background: var(--primary-soft); }
.hero-note { margin-top: 24px; padding: 16px 18px; border-left: 5px solid var(--primary); border-radius: 12px; background: var(--primary-soft); }
.hero-actions, .form-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.hero-actions { margin-top: 26px; }
.clinical-warning { padding: 28px; border-top: 5px solid var(--danger); }
.clinical-warning h2 { margin: 0 0 12px; font-size: 1.35rem; }
.clinical-warning p { color: var(--muted); }

.button {
  border: 0;
  border-radius: 13px;
  padding: 12px 17px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  cursor: pointer;
  text-decoration: none;
  font-weight: 850;
  transition: transform .16s ease, box-shadow .16s ease, background .16s ease;
}
.button:hover:not(:disabled) { transform: translateY(-1px); }
.button:focus-visible { outline: 3px solid color-mix(in srgb, var(--primary) 45%, transparent); outline-offset: 2px; }
.button:disabled { cursor: not-allowed; opacity: .5; }
.button-primary { color: #fff; background: linear-gradient(135deg, #0f67ad, #173f90); box-shadow: 0 10px 24px rgba(21, 80, 150, .22); }
.button-primary:hover:not(:disabled) { background: linear-gradient(135deg, #0d5c9b, #123779); }
.button-secondary { color: var(--text); background: var(--surface-soft); border: 1px solid var(--border); }
.button-ghost { color: var(--text); background: transparent; border: 1px solid var(--border); }
.button-small { padding: 9px 12px; font-size: .85rem; }

.module-section { padding-block: 42px; scroll-margin-top: 82px; }
.module-heading { margin-bottom: 22px; display: flex; align-items: end; justify-content: space-between; gap: 20px; }
.module-heading h2 { margin: 7px 0 4px; font-size: clamp(1.85rem, 4vw, 3rem); letter-spacing: -0.035em; }
.module-heading p { margin: 0; color: var(--muted); }
.module-number { padding: 7px 11px; color: var(--primary); background: var(--primary-soft); }
.public-label { padding: 9px 14px; color: var(--success); background: var(--success-soft); white-space: nowrap; }
.calculator-layout { display: grid; grid-template-columns: minmax(0, 1fr) minmax(360px, .62fr); gap: 22px; align-items: start; }
.form-panel, .result-panel { padding: clamp(20px, 4vw, 32px); }
.result-panel { position: sticky; top: 94px; }
fieldset { margin: 0 0 30px; padding: 0; border: 0; }
legend { padding: 0; margin-bottom: 14px; font-size: 1.15rem; font-weight: 900; }
.fieldset-help { margin: 12px 0 0; color: var(--muted); font-size: .88rem; }
.form-grid { display: grid; gap: 16px; }
.form-grid.two-columns { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.form-grid.three-columns { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.field { display: flex; flex-direction: column; gap: 7px; }
.field > span { font-size: .9rem; font-weight: 820; }
.field small { color: var(--muted); font-size: .79rem; }
input, select, .field-static output {
  width: 100%;
  min-height: 46px;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 10px 12px;
  color: var(--text);
  background: var(--surface);
  outline: none;
}
.field-static output { display: flex; align-items: center; color: var(--muted); background: var(--surface-soft); }
input:focus, select:focus { border-color: var(--primary); box-shadow: 0 0 0 4px color-mix(in srgb, var(--primary) 14%, transparent); }
input.invalid, select.invalid { border-color: var(--danger); box-shadow: 0 0 0 4px color-mix(in srgb, var(--danger) 12%, transparent); }
.form-errors { margin-bottom: 22px; border: 1px solid color-mix(in srgb, var(--danger) 38%, var(--border)); border-radius: 14px; padding: 14px 16px; color: var(--danger); background: var(--danger-soft); }
.form-errors strong { display: block; margin-bottom: 4px; }
.form-errors ul { margin: 0; padding-left: 20px; }
.electrolyte-block { margin-top: 14px; padding: 18px; border: 1px solid var(--border); border-radius: 16px; background: var(--surface-soft); }
.electrolyte-title { margin-bottom: 14px; display: flex; justify-content: space-between; gap: 12px; }
.electrolyte-title strong { font-size: 1rem; }
.electrolyte-title span { color: var(--muted); font-size: .84rem; font-weight: 750; }
.magnesium-custom { margin-top: 14px; }

.empty-result { min-height: 440px; display: grid; place-content: center; text-align: center; color: var(--muted); }
.empty-result h3 { margin: 14px 0 6px; color: var(--text); }
.empty-icon { font-size: 3rem; }
.result-heading { padding-bottom: 20px; border-bottom: 1px solid var(--border); }
.result-heading h3 { margin: 8px 0 4px; font-size: 1.65rem; letter-spacing: -.025em; }
.result-kicker { padding: 6px 10px; color: var(--success); background: var(--success-soft); }
.muted { color: var(--muted); }
.summary-grid { margin: 20px 0; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.summary-card { padding: 16px; border: 1px solid var(--border); border-radius: 16px; background: var(--surface-soft); }
.summary-card span { display: block; color: var(--muted); font-size: .78rem; font-weight: 750; }
.summary-card strong { display: block; margin-top: 6px; font-size: 1.35rem; line-height: 1.15; }
.result-section { padding: 20px 0; border-top: 1px solid var(--border); }
.result-section h4 { margin: 0 0 12px; font-size: 1.05rem; }
.data-table { overflow: hidden; border: 1px solid var(--border); border-radius: 14px; }
.data-row { min-height: 44px; padding: 10px 12px; display: grid; grid-template-columns: minmax(0, 1fr) auto; align-items: center; gap: 16px; background: var(--surface); }
.data-row:nth-child(even) { background: var(--surface-soft); }
.data-row span { color: var(--muted); font-size: .86rem; }
.data-row strong { text-align: right; font-size: .9rem; }
.alerts-list { display: grid; gap: 10px; }
.alert-item { padding: 13px 14px; border-radius: 13px; border: 1px solid var(--border); background: var(--surface-soft); }
.alert-item.warning { border-color: color-mix(in srgb, var(--warning) 40%, var(--border)); background: var(--warning-soft); }
.alert-item.danger { border-color: color-mix(in srgb, var(--danger) 40%, var(--border)); background: var(--danger-soft); }
.result-disclaimer { margin-top: 20px; padding: 15px 16px; border-left: 5px solid var(--warning); border-radius: 12px; background: var(--warning-soft); font-size: .88rem; }

.section-block { padding-block: 18px 52px; }
.explanation-panel { padding: clamp(24px, 5vw, 40px); }
.explanation-panel h2 { margin: 8px 0 22px; font-size: clamp(1.7rem, 4vw, 2.6rem); }
.explanation-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; }
.explanation-grid article { padding: 18px; border: 1px solid var(--border); border-radius: 16px; background: var(--surface-soft); }
.explanation-grid p { margin: 7px 0 0; color: var(--muted); font-size: .9rem; }
.site-footer { margin-top: 30px; border-top: 1px solid var(--border); background: var(--surface); }
.footer-grid { padding: 30px 0; display: grid; grid-template-columns: .45fr 1fr; gap: 28px; }
.footer-grid p { margin: 6px 0 0; color: var(--muted); }
.footer-note { font-size: .9rem; }

@media (max-width: 1020px) {
  .hero-grid, .calculator-layout { grid-template-columns: 1fr; }
  .result-panel { position: static; }
  .form-grid.three-columns { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .explanation-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 780px) {
  .main-nav { display: none; }
  .header-inner { justify-content: space-between; }
  .module-heading { align-items: flex-start; flex-direction: column; }
  .form-grid.two-columns, .form-grid.three-columns, .summary-grid, .explanation-grid, .footer-grid { grid-template-columns: 1fr; }
  .hero { padding-top: 24px; }
  .hero-main h1 { font-size: clamp(2.15rem, 13vw, 3.4rem); }
  .button { width: 100%; }
  .button-small { width: auto; }
  .form-actions { display: grid; }
}
@media (max-width: 480px) {
  .container { width: min(100% - 20px, 1180px); }
  .form-panel, .result-panel, .hero-main, .clinical-warning { padding: 20px; border-radius: 18px; }
  .data-row { grid-template-columns: 1fr; gap: 4px; }
  .data-row strong { text-align: left; }
}

@media print {
  @page { size: A4; margin: 12mm; }
  :root { color-scheme: light; }
  html, body { background: #fff !important; color: #111 !important; font-size: 10.5pt; }
  .no-print, .site-header, .hero, .module-heading, .form-panel, .site-footer, #como-funciona { display: none !important; }
  .print-only { display: block !important; }
  .container, .module-section { width: 100% !important; max-width: none !important; margin: 0 !important; padding: 0 !important; }
  .calculator-layout { display: block !important; }
  .result-panel { position: static !important; border: 0 !important; border-radius: 0 !important; box-shadow: none !important; padding: 0 !important; }
  .print-header { padding-bottom: 12px; border-bottom: 2px solid #0f4c81; }
  .print-brand { color: #0f4c81; font-size: 15pt; font-weight: 900; }
  .print-header h1 { margin: 4px 0 10px; font-size: 20pt; }
  .print-patient-info { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 4px 18px; font-size: 9.5pt; }
  .result-heading { margin-top: 14px; }
  .result-kicker { border: 1px solid #bbb; background: #fff !important; color: #111 !important; }
  .summary-grid { grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 6px; }
  .summary-card, .data-table, .alert-item, .result-disclaimer { break-inside: avoid; box-shadow: none !important; }
  .summary-card { padding: 9px; border-radius: 8px; background: #fff !important; }
  .summary-card strong { font-size: 11pt; }
  .result-section { padding: 10px 0; }
  .data-table { border-radius: 6px; }
  .data-row { min-height: 30px; padding: 5px 8px; background: #fff !important; }
  .data-row:nth-child(even) { background: #f4f4f4 !important; }
  .result-disclaimer { background: #fff !important; border: 1px solid #aaa; border-left: 4px solid #777; }
  .print-footer { margin-top: 14px; padding-top: 8px; border-top: 1px solid #aaa; color: #555; font-size: 8.5pt; }
}