/* Shared shell for calculator pages. Load before calculator.css. */
:root {
  --snow: #ffffff;
  --snow-cool: #fafafd;
  --snow-warm: #f8f6f1;
  --ink: #000000;
  --ink-72: rgba(0, 0, 0, 0.72);
  --ink-56: rgba(0, 0, 0, 0.56);
  --ink-40: rgba(0, 0, 0, 0.40);
  --ink-18: rgba(0, 0, 0, 0.18);
  --ink-08: rgba(0, 0, 0, 0.08);
  --ui: ui-rounded, "SF Pro Rounded", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --serif: Georgia, "Times New Roman", serif;
}
* { box-sizing: border-box; }
body { margin: 0; color: var(--ink); background: linear-gradient(180deg, var(--snow-cool), var(--snow-warm)); font-family: var(--ui); line-height: 1.6; min-height: 100vh; }
a { color: inherit; text-underline-offset: 3px; }
.page { width: min(100%, 880px); margin: 0 auto; padding: 28px clamp(20px, 5vw, 48px) 64px; }
header { display: flex; align-items: baseline; justify-content: space-between; gap: 18px; padding-bottom: 28px; }
.wordmark { font-family: var(--serif); font-size: clamp(36px, 8vw, 72px); line-height: 0.9; text-decoration: none; }
.header-nav { display: flex; align-items: center; gap: 18px; flex-wrap: wrap; }
.nav-link { color: var(--ink-56); font-size: 14px; text-decoration: none; }
.nav-link:hover { color: var(--ink); text-decoration: underline; }
.hero { padding: clamp(48px, 10vw, 96px) 0 clamp(48px, 8vw, 80px); border-top: 1px solid var(--ink-08); }
h1 { max-width: 720px; margin: 0 0 28px; font-family: var(--serif); font-size: clamp(52px, 11vw, 96px); font-weight: 400; line-height: 0.92; }
.tagline { max-width: 560px; margin: 0; color: var(--ink-72); font-size: clamp(18px, 3vw, 22px); line-height: 1.5; }
.links { display: flex; align-items: center; gap: 24px; margin-top: 32px; flex-wrap: wrap; }
.link-privacy { color: var(--ink-56); font-size: 14px; text-decoration: none; }
.link-privacy:hover { color: var(--ink); text-decoration: underline; }
footer { padding-top: 80px; color: var(--ink-40); font-size: 13px; }
@media (max-width: 680px) {
  header { display: block; }
  .header-nav { margin-top: 12px; }
}

/* Long-form guide below the calculator */
.guide { max-width: 740px; margin-top: 48px; }
.guide h2 { font-size: 28px; line-height: 1.15; letter-spacing: -.04em; margin: 44px 0 12px; }
.guide h3 { font-size: 18px; line-height: 1.25; margin: 26px 0 8px; }
.guide p, .guide li { color: #3a3a3a; font-size: 16px; line-height: 1.65; }
.guide p { margin: 0 0 16px; }
.guide ul, .guide ol { margin: 0 0 16px; padding-left: 1.25rem; }
.guide li + li { margin-top: 6px; }
.guide a { color: var(--ink); }
.guide table { width: 100%; border-collapse: collapse; margin: 16px 0 22px; font-size: 14px; }
.guide th { text-align: left; color: #666; font-size: 11px; font-weight: 600; text-transform: uppercase; letter-spacing: .06em; padding: 8px 10px 8px 0; border-bottom: 1px solid #ddd; }
.guide td { padding: 10px 10px 10px 0; border-bottom: 1px solid #e5e5e5; vertical-align: top; }
.guide .table-wrap { overflow-x: auto; }
.guide .callout { margin: 22px 0; padding: 18px; border: 1px solid #d1d1d1; border-radius: 12px; background: #fafafa; }
.guide .callout p:last-child { margin-bottom: 0; }
.habit-links { margin-top: 36px; padding: 24px 0; border-top: 1px solid #ddd; }
.habit-links p { margin: 0 0 10px; font-size: 14px; color: #626262; }
.habit-links ul { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: 10px; }
.habit-links a { display: inline-block; padding: 9px 14px; border: 1px solid #ccc; border-radius: 999px; font-size: 14px; font-weight: 600; text-decoration: none; background: white; }
.habit-links a:hover, .habit-links a[aria-current="page"] { background: black; color: white; border-color: black; }
.breadcrumb { font-size: 13px; color: #626262; margin: 0 0 22px; }
.breadcrumb a { text-decoration: none; }
.breadcrumb a:hover { text-decoration: underline; }
.habit-links-top { margin-top: 28px; padding: 0; border-top: 0; }
.habit-links-top + .calculator { margin-top: 28px; }