/* ==========================================================================
   DailyKitBox — BMI Calculator
   Design tokens: dark navy base, vivid red accent, Syne + DM Sans
   ========================================================================== */

:root {
  --bg: #090D16;
  --bg-elev: #10151F;
  --bg-elev-2: #161C2A;
  --card: rgba(255,255,255,0.035);
  --card-border: rgba(255,255,255,0.09);
  --card-border-strong: rgba(255,255,255,0.16);
  --text: #EDEFF3;
  --text-dim: #9AA3B5;
  --text-faint: #6B7386;
  --accent: #FF3B5C;
  --accent-2: #FF7A59;
  --accent-soft: rgba(255,59,92,0.14);
  --focus-ring: #6FA8FF;

  --zone-under: #4DA3FF;
  --zone-normal: #2ECC71;
  --zone-over: #FFB020;
  --zone-obese: #FF5A5F;
  --zone-severe: #C0392B;

  --font-display: 'Syne', system-ui, sans-serif;
  --font-body: 'DM Sans', system-ui, -apple-system, sans-serif;

  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --shadow-card: 0 20px 60px -20px rgba(0,0,0,0.55);
  --shadow-soft: 0 8px 24px -8px rgba(0,0,0,0.4);

  --max-width: 1180px;
  --header-h: 68px;

  color-scheme: dark;
}

:root[data-theme="light"] {
  --bg: #F5F6FA;
  --bg-elev: #FFFFFF;
  --bg-elev-2: #FFFFFF;
  --card: #FFFFFF;
  --card-border: rgba(10,14,25,0.09);
  --card-border-strong: rgba(10,14,25,0.16);
  --text: #12141C;
  --text-dim: #545B6B;
  --text-faint: #868FA0;
  --accent-soft: rgba(255,59,92,0.09);
  --shadow-card: 0 20px 50px -24px rgba(20,24,40,0.22);
  --shadow-soft: 0 8px 20px -10px rgba(20,24,40,0.16);
  color-scheme: light;
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; transition-duration: 0.01ms !important; scroll-behavior: auto !important; }
}
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  transition: background-color 0.25s ease, color 0.25s ease;
}
img, svg { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: none; cursor: pointer; }
input, select { font: inherit; color: inherit; }
ul, ol { margin: 0; padding: 0; list-style: none; }
h1, h2, h3 { font-family: var(--font-display); font-weight: 700; line-height: 1.15; margin: 0; }
p { margin: 0; }

:focus-visible {
  outline: 2px solid var(--focus-ring);
  outline-offset: 2px;
  border-radius: 4px;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--accent);
  color: #fff;
  padding: 12px 20px;
  z-index: 1000;
  border-radius: 0 0 8px 0;
}
.skip-link:focus { left: 0; }

.section-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  background: rgba(9,13,22,0.72);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  border-bottom: 1px solid var(--card-border);
}
:root[data-theme="light"] .site-header { background: rgba(255,255,255,0.78); }
.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  height: 100%;
  padding: 0 20px;
  display: flex;
  align-items: center;
  gap: 20px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.05rem;
  flex-shrink: 0;
}
.brand-mark { width: 22px; height: 22px; fill: var(--accent); }
.breadcrumb-nav { flex: 1; min-width: 0; overflow: hidden; }
.breadcrumb-nav ol { display: flex; gap: 8px; align-items: center; font-size: 0.85rem; color: var(--text-dim); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.breadcrumb-nav a:hover { color: var(--text); }
.breadcrumb-nav li[aria-current] { color: var(--text); font-weight: 600; }
.header-actions { display: flex; align-items: center; gap: 14px; flex-shrink: 0; }
.all-tools-link {
  font-size: 0.85rem;
  font-weight: 600;
  padding: 8px 14px;
  border: 1px solid var(--card-border-strong);
  border-radius: 999px;
  transition: border-color 0.2s ease, background-color 0.2s ease;
}
.all-tools-link:hover { border-color: var(--accent); background: var(--accent-soft); }

.theme-toggle {
  width: 38px; height: 38px;
  display: grid; place-items: center;
  border-radius: 50%;
  border: 1px solid var(--card-border-strong);
}
.theme-toggle svg { width: 18px; height: 18px; fill: none; stroke: var(--text); stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.theme-toggle .icon-moon { display: none; }
:root[data-theme="light"] .theme-toggle .icon-sun { display: none; }
:root[data-theme="light"] .theme-toggle .icon-moon { display: block; }

/* ---------- Hero ---------- */
.hero { padding: 56px 0 24px; position: relative; overflow: hidden; }
.hero::before {
  content: "";
  position: absolute;
  top: -140px; left: 50%;
  width: 640px; height: 320px;
  transform: translateX(-50%);
  background: radial-gradient(ellipse at center, var(--accent-soft), transparent 70%);
  pointer-events: none;
}
.hero-inner { max-width: var(--max-width); margin: 0 auto; padding: 0 20px; position: relative; }
.hero-copy { max-width: 640px; }
.eyebrow { font-size: 0.8rem; font-weight: 700; letter-spacing: 0.08em; text-transform: uppercase; color: var(--accent); margin-bottom: 12px; }
.hero h1 { font-size: clamp(2.1rem, 5vw, 3.2rem); letter-spacing: -0.02em; margin-bottom: 14px; }
.hero-sub { color: var(--text-dim); font-size: 1.05rem; max-width: 52ch; margin-bottom: 20px; }
.trust-badges { display: flex; flex-wrap: wrap; gap: 10px 20px; }
.trust-badges li { display: flex; align-items: center; gap: 6px; font-size: 0.85rem; font-weight: 600; color: var(--text-dim); }
.trust-badges svg { width: 16px; height: 16px; fill: none; stroke: var(--zone-normal); stroke-width: 2.5; stroke-linecap: round; stroke-linejoin: round; }

/* ---------- Calculator grid ---------- */
.calculator-section { padding: 20px 0 60px; }
.calculator-grid {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
  display: grid;
  grid-template-columns: minmax(0,420px) minmax(0,1fr);
  gap: 24px;
  align-items: start;
}

.calc-card, .result-card {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow-card);
  backdrop-filter: blur(6px);
}

.unit-switch, .pill-switch {
  display: inline-flex;
  background: var(--bg-elev-2);
  border: 1px solid var(--card-border);
  border-radius: 999px;
  padding: 4px;
  gap: 4px;
}
.unit-switch { width: 100%; margin-bottom: 22px; }
.unit-btn, .pill-btn {
  flex: 1;
  padding: 9px 16px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.88rem;
  color: var(--text-dim);
  transition: background-color 0.2s ease, color 0.2s ease;
  white-space: nowrap;
}
.unit-btn.is-active, .pill-btn.is-active {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff;
}

.field-row.two-col { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.field-group, .field { margin-bottom: 18px; }
.field-group label, .field label, .field-label {
  display: block;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-dim);
  margin-bottom: 8px;
}
.field-optional { font-weight: 400; color: var(--text-faint); }
.input-wrap {
  position: relative;
  display: flex;
  align-items: center;
  background: var(--bg-elev-2);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-sm);
  transition: border-color 0.2s ease;
}
.input-wrap:focus-within { border-color: var(--accent); }
.input-wrap input {
  width: 100%;
  background: transparent;
  border: none;
  padding: 13px 14px;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text);
  min-width: 0;
}
.input-wrap input:focus { outline: none; }
.input-wrap input::-webkit-outer-spin-button, .input-wrap input::-webkit-inner-spin-button { margin: 0; }
.input-suffix { padding-right: 14px; font-size: 0.85rem; color: var(--text-faint); font-weight: 600; }
.field-hint { font-size: 0.75rem; color: var(--text-faint); margin-top: 6px; }
.is-hidden { display: none !important; }

select#activityLevel {
  width: 100%;
  padding: 13px 14px;
  background: var(--bg-elev-2);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-weight: 500;
  font-size: 0.92rem;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%239AA3B5' stroke-width='2'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 18px;
  padding-right: 38px;
}

.form-actions { display: flex; gap: 12px; margin-top: 22px; }
.btn-primary, .btn-ghost {
  flex: 1;
  padding: 14px 20px;
  border-radius: 999px;
  font-weight: 700;
  font-size: 0.95rem;
  text-align: center;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background-color 0.15s ease;
}
.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff;
  box-shadow: 0 12px 28px -10px rgba(255,59,92,0.55);
}
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 16px 32px -10px rgba(255,59,92,0.65); }
.btn-primary:active { transform: translateY(0); }
.btn-ghost { flex: 0 0 auto; border: 1px solid var(--card-border-strong); color: var(--text-dim); }
.btn-ghost:hover { border-color: var(--text-dim); color: var(--text); }
.disclaimer-inline { font-size: 0.75rem; color: var(--text-faint); margin-top: 14px; }
.disclaimer-inline a { color: var(--accent); font-weight: 600; }

/* ---------- Result card ---------- */
.result-card { min-height: 480px; display: flex; flex-direction: column; }
.result-empty {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  gap: 14px;
  color: var(--text-faint);
  padding: 40px 20px;
}
.result-empty svg { width: 44px; height: 44px; fill: none; stroke: var(--text-faint); stroke-width: 1.6; }
.result-empty p { max-width: 30ch; font-size: 0.95rem; }

.gauge-wrap { position: relative; display: flex; justify-content: center; margin-bottom: 6px; }
.gauge { width: 100%; max-width: 320px; }
.gauge-track { stroke: var(--card-border-strong); stroke-width: 16; stroke-linecap: round; }
.gauge-value { stroke-width: 16; stroke-linecap: round; stroke-dasharray: 314; stroke-dashoffset: 314; transition: stroke-dashoffset 1s cubic-bezier(.22,1,.36,1); }
.gauge-needle { stroke: var(--text); stroke-width: 4; stroke-linecap: round; transform-origin: 120px 130px; transform: rotate(-90deg); transition: transform 1s cubic-bezier(.22,1,.36,1); }
.gauge-hub { fill: var(--text); }
.gauge-readout { position: absolute; bottom: 4px; left: 50%; transform: translateX(-50%); text-align: center; }
.gauge-number { display: block; font-family: var(--font-display); font-size: 2.6rem; font-weight: 800; line-height: 1; }
.gauge-label { font-size: 0.75rem; color: var(--text-faint); font-weight: 700; letter-spacing: 0.06em; text-transform: uppercase; }

.category-badge {
  text-align: center;
  font-weight: 700;
  font-size: 1.05rem;
  padding: 10px 18px;
  border-radius: 999px;
  margin: 12px auto 20px;
  width: fit-content;
}
.category-badge[data-zone="under"] { background: rgba(77,163,255,0.16); background: color-mix(in srgb, var(--zone-under) 18%, transparent); color: var(--zone-under); }
.category-badge[data-zone="normal"] { background: rgba(46,204,113,0.16); background: color-mix(in srgb, var(--zone-normal) 18%, transparent); color: var(--zone-normal); }
.category-badge[data-zone="over"] { background: rgba(255,176,32,0.16); background: color-mix(in srgb, var(--zone-over) 18%, transparent); color: var(--zone-over); }
.category-badge[data-zone="obese"] { background: rgba(255,90,95,0.16); background: color-mix(in srgb, var(--zone-obese) 18%, transparent); color: var(--zone-obese); }
.category-badge[data-zone="severe"] { background: rgba(192,57,43,0.16); background: color-mix(in srgb, var(--zone-severe) 18%, transparent); color: var(--zone-severe); }

.stats-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-bottom: 20px; }
.stat { background: var(--bg-elev-2); border: 1px solid var(--card-border); border-radius: var(--radius-sm); padding: 14px 16px; }
.stat-wide { grid-column: 1 / -1; }
.stat-label { display: block; font-size: 0.72rem; color: var(--text-faint); font-weight: 600; text-transform: uppercase; letter-spacing: 0.04em; margin-bottom: 6px; }
.stat-value { font-weight: 700; font-size: 1.05rem; }

.tips-card { background: var(--bg-elev-2); border: 1px solid var(--card-border); border-radius: var(--radius-md); padding: 18px 20px; }
.tips-card h3 { font-size: 0.95rem; margin-bottom: 10px; }
.tips-card ul { display: flex; flex-direction: column; gap: 8px; }
.tips-card li { position: relative; padding-left: 20px; font-size: 0.9rem; color: var(--text-dim); }
.tips-card li::before { content: "→"; position: absolute; left: 0; color: var(--accent); font-weight: 700; }

/* ---------- Bonus tools ---------- */
.bonus-tools { padding: 20px 0 60px; }
.bonus-tools h2 { font-size: 1.5rem; margin-bottom: 18px; }
.bonus-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.bonus-card { background: var(--card); border: 1px solid var(--card-border); border-radius: var(--radius-md); padding: 22px; box-shadow: var(--shadow-soft); }
.bonus-icon { display: inline-grid; place-items: center; width: 40px; height: 40px; border-radius: 12px; background: var(--accent-soft); margin-bottom: 12px; }
.bonus-icon svg { width: 20px; height: 20px; fill: none; stroke: var(--accent); stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.bonus-card h3 { font-size: 1rem; margin-bottom: 6px; }
.bonus-value { font-family: var(--font-display); font-size: 1.6rem; font-weight: 800; margin-bottom: 6px; }
.bonus-note { font-size: 0.83rem; color: var(--text-faint); }
.bonus-footnote { margin-top: 16px; font-size: 0.83rem; color: var(--text-faint); }

/* ---------- Share section ---------- */
.share-section { padding: 40px 0; background: var(--bg-elev); border-top: 1px solid var(--card-border); border-bottom: 1px solid var(--card-border); }
.share-inner { display: flex; flex-direction: column; gap: 20px; }
.share-copy h2 { font-size: 1.4rem; margin-bottom: 6px; }
.share-copy p { color: var(--text-dim); font-size: 0.92rem; }
.share-actions { display: flex; flex-wrap: wrap; gap: 10px; }
.share-btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 10px 16px;
  border-radius: 999px;
  border: 1px solid var(--card-border-strong);
  font-size: 0.85rem; font-weight: 600;
  transition: transform 0.15s ease, border-color 0.15s ease, background-color 0.15s ease;
}
.share-btn svg { width: 16px; height: 16px; fill: currentColor; }
.share-btn:hover { transform: translateY(-2px); }
.share-pinterest:hover { color: #E60023; border-color: #E60023; background: rgba(230,0,35,0.08); }
.share-facebook:hover { color: #1877F2; border-color: #1877F2; background: rgba(24,119,242,0.08); }
.share-x:hover { color: var(--text); border-color: var(--text-dim); }
.share-linkedin:hover { color: #0A66C2; border-color: #0A66C2; background: rgba(10,102,194,0.08); }
.share-reddit:hover { color: #FF4500; border-color: #FF4500; background: rgba(255,69,0,0.08); }
.share-whatsapp:hover { color: #25D366; border-color: #25D366; background: rgba(37,211,102,0.08); }

.embed-row { max-width: 480px; }
.copy-input-wrap { display: flex; gap: 8px; }
.copy-input-wrap input {
  flex: 1; min-width: 0;
  background: var(--bg-elev-2);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-sm);
  padding: 11px 14px;
  font-size: 0.85rem;
  color: var(--text-dim);
}
.btn-copy {
  padding: 11px 18px;
  border-radius: var(--radius-sm);
  background: var(--accent);
  color: #fff;
  font-weight: 700;
  font-size: 0.85rem;
  flex-shrink: 0;
}
.copy-feedback { font-size: 0.78rem; color: var(--zone-normal); margin-top: 8px; min-height: 1em; }

/* ---------- How-to ---------- */
.how-to { padding: 60px 0; }
.how-to h2 { font-size: 1.6rem; margin-bottom: 28px; }
.steps-list { display: flex; flex-direction: column; gap: 20px; }
.steps-list li { display: flex; gap: 16px; align-items: flex-start; }
.step-num {
  flex-shrink: 0;
  width: 34px; height: 34px;
  display: grid; place-items: center;
  border-radius: 50%;
  background: var(--accent-soft);
  color: var(--accent);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 0.9rem;
}
.steps-list h3 { font-size: 1rem; margin-bottom: 4px; }
.steps-list p { color: var(--text-dim); font-size: 0.9rem; }

/* ---------- About / prose ---------- */
.about { padding: 20px 0 60px; background: var(--bg-elev); border-top: 1px solid var(--card-border); border-bottom: 1px solid var(--card-border); }
.prose { max-width: 760px; padding-top: 40px; padding-bottom: 20px; }
.prose h2 { font-size: 1.7rem; margin-bottom: 20px; }
.prose h3 { font-size: 1.15rem; margin: 32px 0 10px; }
.prose p { color: var(--text-dim); margin-bottom: 14px; font-size: 0.97rem; }
.formula-block {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--text);
  background: var(--bg-elev-2);
  border-left: 3px solid var(--accent);
  padding: 12px 16px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin-bottom: 16px;
}
.category-list { display: flex; flex-direction: column; gap: 6px; margin-bottom: 16px; }
.category-list li { font-size: 0.94rem; color: var(--text-dim); padding: 8px 0; border-bottom: 1px dashed var(--card-border); }
.category-list strong { color: var(--text); }

/* ---------- FAQ ---------- */
.faq { padding: 60px 0; }
.faq h2 { font-size: 1.6rem; margin-bottom: 24px; }
.faq-list { display: flex; flex-direction: column; gap: 10px; }
.faq-item {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-md);
  padding: 4px 20px;
}
.faq-item summary {
  cursor: pointer;
  list-style: none;
  padding: 16px 28px 16px 0;
  font-weight: 600;
  font-size: 0.96rem;
  position: relative;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 0; top: 14px;
  font-size: 1.3rem;
  color: var(--accent);
  transition: transform 0.2s ease;
}
.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-item p { color: var(--text-dim); font-size: 0.9rem; padding-bottom: 18px; }

/* ---------- Disclaimers ---------- */
.disclaimers { padding: 20px 0 60px; }
.disclaimers h2 { font-size: 1.5rem; margin-bottom: 20px; }
.disclaimer-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; margin-bottom: 24px; }
.disclaimer-card { background: var(--bg-elev-2); border: 1px solid var(--card-border); border-radius: var(--radius-md); padding: 18px; }
.disclaimer-card h3 { font-size: 0.92rem; margin-bottom: 6px; color: var(--accent-2); }
.disclaimer-card p { font-size: 0.83rem; color: var(--text-faint); }
.legal-note { font-size: 0.82rem; color: var(--text-faint); line-height: 1.7; }
.legal-note a { color: var(--accent); font-weight: 600; }

/* ---------- Internal links ---------- */
.internal-links { padding: 20px 0 60px; }
.internal-links h2 { font-size: 1.5rem; margin-bottom: 20px; }
.related-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
.related-card {
  display: flex; align-items: center; justify-content: space-between;
  padding: 16px 18px;
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.9rem;
  transition: border-color 0.2s ease, transform 0.2s ease;
}
.related-card:hover { border-color: var(--accent); transform: translateX(2px); }
.related-card svg { width: 16px; height: 16px; fill: none; stroke: var(--accent); stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }

/* ---------- Footer ---------- */
.site-footer { padding: 28px 0; border-top: 1px solid var(--card-border); }
.footer-inner { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; align-items: center; }
.footer-inner p { font-size: 0.8rem; color: var(--text-faint); }
.footer-links { display: flex; gap: 18px; }
.footer-links a { font-size: 0.8rem; color: var(--text-dim); font-weight: 600; }
.footer-links a:hover { color: var(--accent); }

/* ---------- Responsive ---------- */
@media (max-width: 980px) {
  .calculator-grid { grid-template-columns: 1fr; }
  .bonus-grid { grid-template-columns: 1fr; }
  .disclaimer-grid { grid-template-columns: 1fr 1fr; }
  .related-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 640px) {
  .header-inner { gap: 12px; }
  .breadcrumb-nav { display: none; }
  .all-tools-link { display: none; }
  .hero { padding: 36px 0 16px; }
  .calc-card, .result-card { padding: 20px; }
  .field-row.two-col { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: 1fr; }
  .disclaimer-grid { grid-template-columns: 1fr; }
  .related-grid { grid-template-columns: 1fr; }
  .form-actions { flex-direction: column; }
  .btn-ghost { flex: 1; }
  .share-inner { align-items: flex-start; }
}