/* Ski Length Calculator — Glacier Patrol design system.
   Navy #17384F / ice #8FC1E3 / patrol orange #E4572E / snow #F2F7FA.
   Angular alpine geometry: clipped corners, ridgeline dividers, one
   centered column on every page (centered hero, centered calculator
   panel, centered text sections), and range-bar results. */

:root {
  --bg: #f2f7fa;               /* snow */
  --surface: #e3eef5;          /* pale ice */
  --card: #ffffff;             /* fresh snow card */
  --text: #14242f;             /* deep slate ink */
  --muted: #51707f;            /* glacier gray-blue */
  --border: #c3d5df;
  --border-strong: #8fc1e3;    /* ice */
  --accent: #17384f;           /* glacier navy */
  --accent-deep: #0f2739;      /* navy, deep */
  --accent-ink: #17384f;
  --accent-contrast: #f2f7fa;
  --accent-soft: #dcebf4;
  --pop: #e4572e;              /* patrol orange */
  --pop-deep: #b23c1a;         /* orange for text on snow */
  --pop-soft: #fdeee7;
  --navy: #17384f;             /* header band */
  --navy-deep: #0d2233;        /* footer */
  --navy-ink: #f2f7fa;
  --navy-muted: #a9c8da;
  --success: #2e7d4f;
  --danger: #b3352b;
  --shadow: 0 12px 30px rgba(23, 56, 79, 0.16);
  --clip: polygon(0 0, calc(100% - 14px) 0, 100% 14px, 100% 100%, 14px 100%, 0 calc(100% - 14px));
  --clip-sm: polygon(0 0, calc(100% - 9px) 0, 100% 9px, 100% 100%, 9px 100%, 0 calc(100% - 9px));

  --fs-xs: 0.8125rem;
  --fs-sm: 0.875rem;
  --fs-base: 1rem;
  --fs-lg: 1.125rem;
  --fs-xl: 1.25rem;
  --fs-2xl: 1.5rem;
  --fs-3xl: 2rem;
  --fs-4xl: 2.75rem;

  --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, sans-serif;
  --font-display: "Avenir Next", "Trebuchet MS", -apple-system,
    BlinkMacSystemFont, "Segoe UI", sans-serif;
  --max-width: 74rem;
  --measure: 72ch;
  --radius: 0.25rem;
  --radius-lg: 0.375rem;

  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 1rem;
  --space-4: 1.5rem;
  --space-5: 2.5rem;
  --space-6: 4rem;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-stack);
  font-size: var(--fs-base);
  line-height: 1.6;
  overflow-x: clip;
}

img { max-width: 100%; height: auto; }

.wrap {
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--space-3);
}
.wrap--wide { max-width: 88rem; }
/* The one content column used site-wide: text sections, page heads and
   the chart page's prose all share this centered measure. */
.wrap--text { max-width: 53.75rem; }

h1, h2, h3 {
  font-family: var(--font-display);
  line-height: 1.15;
  letter-spacing: -0.01em;
  color: var(--accent-deep);
}
h2 { font-size: var(--fs-2xl); margin: 0 0 var(--space-3); }
h3 { font-size: var(--fs-lg); }

a { color: var(--accent); text-underline-offset: 2px; }
a:hover { color: var(--pop-deep); }

section { margin-block: var(--space-5); }
section:first-child { margin-top: 0; }
p { max-width: var(--measure); }

.visually-hidden {
  position: absolute; width: 1px; height: 1px; overflow: hidden;
  clip: rect(0 0 0 0); white-space: nowrap;
}

.skip-link {
  position: absolute; left: -9999px; top: 0; z-index: 60;
  background: var(--navy-deep); color: var(--navy-ink);
  padding: var(--space-2) var(--space-3);
}
.skip-link:focus { left: var(--space-2); top: var(--space-2); }

/* ---------- header ---------- */
.site-header {
  background: var(--navy);
  color: var(--navy-ink);
  position: relative;
  z-index: 40;
}
.site-header__inner {
  max-width: var(--max-width);
  margin-inline: auto;
  padding: var(--space-2) var(--space-3);
  display: flex; align-items: center; justify-content: space-between; gap: var(--space-3);
}
.site-logo {
  display: inline-flex; align-items: center; gap: var(--space-2);
  color: var(--navy-ink); text-decoration: none;
  font-family: var(--font-display); font-weight: 700; font-size: 1.2rem;
  letter-spacing: 0.01em;
}
.site-logo:hover { color: var(--navy-ink); }
.site-logo img { display: block; }

.site-nav { position: relative; }
.nav-toggle {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 48px; min-height: 48px;
  background: transparent; border: 1px solid var(--navy-muted);
  color: var(--navy-ink); cursor: pointer; clip-path: var(--clip-sm);
}
.nav-toggle__icon, .nav-toggle__icon::before, .nav-toggle__icon::after {
  display: block; width: 22px; height: 2px; background: currentColor; position: relative;
}
.nav-toggle__icon::before { content: ""; position: absolute; top: -7px; }
.nav-toggle__icon::after { content: ""; position: absolute; top: 7px; }

.site-nav__list {
  list-style: none; margin: 0; padding: 0;
  display: none; flex-direction: column; gap: 2px;
  position: absolute; right: 0; top: calc(100% + 10px);
  background: var(--navy-deep); min-width: 15rem;
  padding: var(--space-2); box-shadow: var(--shadow);
  max-height: calc(100dvh - 5rem); overflow-y: auto;
}
.site-nav.open .site-nav__list { display: flex; }
.site-nav__list a, .site-nav__list button {
  display: flex; align-items: center; width: 100%;
  min-height: 44px; padding: var(--space-2) var(--space-3);
  color: var(--navy-ink); text-decoration: none; background: none; border: 0;
  font: inherit; text-align: left; cursor: pointer;
}
.site-nav__list a:hover, .site-nav__list button:hover { background: rgba(143, 193, 227, 0.16); }
.site-nav__list [aria-current="page"] { color: var(--ice, #8fc1e3); font-weight: 700; }
.has-dropdown { position: relative; }
.has-dropdown > button::after { content: "▾"; margin-left: auto; padding-left: var(--space-2); }
.has-dropdown ul {
  list-style: none; margin: 0; padding: 0 0 0 var(--space-3);
  display: none; flex-direction: column;
}
.has-dropdown > button[aria-expanded="true"] + ul { display: flex; }

/* ---------- breadcrumb ---------- */
.breadcrumb ol {
  list-style: none; display: flex; flex-wrap: wrap; gap: var(--space-2);
  margin: 0; padding: 0; font-size: var(--fs-sm);
}
.breadcrumb li + li::before { content: "›"; margin-right: var(--space-2); color: var(--navy-muted); }
.breadcrumb a { color: var(--ice, #8fc1e3); }
.breadcrumb [aria-current="page"] { color: var(--navy-ink); }

/* ---------- page head band (inner pages) ---------- */
.page-head {
  background: linear-gradient(160deg, var(--navy) 0%, var(--accent-deep) 78%);
  color: var(--navy-ink);
  padding: var(--space-4) 0 var(--space-5);
}
.page-head h1 { color: #fff; font-size: var(--fs-3xl); margin: var(--space-2) 0 var(--space-3); }
.page-head p { color: var(--navy-muted); }
.page-head p strong { color: var(--navy-ink); }
.page-head a { color: var(--ice, #8fc1e3); }
.page-head--plain { background: none; color: var(--text); padding: var(--space-4) 0 0; }
.page-head--plain h1 { color: var(--accent-deep); }
.page-head--plain p { color: var(--muted); }

/* ---------- ridgeline divider ---------- */
.ridgeline { color: var(--border-strong); line-height: 0; }
.ridgeline svg { width: 100%; height: 44px; display: block; }
.ridgeline--hero { color: var(--pop); margin-top: calc(-1 * var(--space-2)); }
.ridgeline--head { color: var(--border-strong); }
.ridgeline--head svg { height: 30px; }
.ridgeline--footer { color: rgba(143, 193, 227, 0.5); }
.ridgeline--footer svg { height: 34px; }

/* ---------- hero (homepage) ---------- */
.hero {
  background: linear-gradient(160deg, var(--navy) 0%, var(--accent-deep) 80%);
  color: var(--navy-ink);
  padding: var(--space-5) 0;
  margin: 0;
  text-align: center;
}
.hero h1 { color: #fff; font-size: var(--fs-4xl); margin: var(--space-2) 0 var(--space-3); }
.hero p { color: var(--navy-muted); font-size: var(--fs-lg); margin-inline: auto; }
.hero p strong { color: var(--navy-ink); }
.hero a { color: var(--ice, #8fc1e3); }
.kicker {
  text-transform: uppercase; letter-spacing: 0.14em; font-size: var(--fs-xs);
  font-weight: 700; color: var(--pop); margin: 0;
}

/* ---------- centered calculator panel ---------- */
/* The calculator is the centerpiece of its page: capped at panel width
   and centered in the text column, on the homepage and inner pages. */
.calc-panel { max-width: 46.25rem; margin-inline: auto; }
.calc-panel .tool { width: 100%; }

/* ---------- calculator panel ---------- */
.tool {
  background: var(--card);
  clip-path: var(--clip);
  box-shadow: var(--shadow);
  padding: var(--space-4);
  margin-block: var(--space-5);
}
.tool > h2 { margin-top: 0; }
.tool__step { margin-top: var(--space-4); }
.tool__step-label {
  font-family: var(--font-display); font-weight: 700; margin: 0 0 var(--space-2);
  display: flex; align-items: center; gap: var(--space-2);
}
.step-badge {
  display: inline-flex; align-items: center; justify-content: center;
  width: 1.6rem; height: 1.6rem; flex: none;
  background: var(--pop); color: #fff; font-size: var(--fs-sm);
  clip-path: polygon(0 0, calc(100% - 7px) 0, 100% 7px, 100% 100%, 7px 100%, 0 calc(100% - 7px));
}
.field-grid { display: grid; gap: var(--space-3); }
.field { display: flex; flex-direction: column; gap: var(--space-1); }
.field label { font-weight: 600; font-size: var(--fs-sm); }
.field .help { font-weight: 400; color: var(--muted); font-size: var(--fs-xs); display: block; }
.unit-hint { color: var(--muted); font-weight: 400; }
.field input, .field select, .field textarea {
  min-height: 3.25rem;
  font-size: 1.0625rem;
  font-family: inherit;
  padding: var(--space-2) var(--space-3);
  border: 1.5px solid var(--border-strong);
  border-radius: var(--radius);
  background: #fff; color: var(--text); width: 100%;
}
.field textarea { min-height: 6rem; }
.field input[aria-invalid="true"], .field select[aria-invalid="true"], .field textarea[aria-invalid="true"] {
  border-color: var(--danger); outline: 2px solid rgba(179, 53, 43, 0.35);
}
.field-check {
  flex-direction: row; align-items: flex-start; gap: var(--space-2);
  padding: var(--space-3); background: var(--surface); border-radius: var(--radius);
}
.field-check input { width: 1.4rem; height: 1.4rem; min-height: 0; flex: none; margin-top: 2px; }

.error-box {
  margin-top: var(--space-3); padding: var(--space-3);
  background: #fbeae8; border-left: 4px solid var(--danger); color: #6d1f19;
}
.btn-row { display: flex; flex-wrap: wrap; gap: var(--space-2); margin-top: var(--space-4); }
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  min-height: 3.25rem; padding: var(--space-2) var(--space-4);
  background: var(--pop); color: #fff; border: 0; cursor: pointer;
  font: inherit; font-weight: 700; text-decoration: none;
  clip-path: var(--clip-sm);
}
.btn:hover { background: var(--pop-deep); color: #fff; }
.btn-ghost {
  display: inline-flex; align-items: center; justify-content: center;
  min-height: 3.25rem; padding: var(--space-2) var(--space-3);
  background: transparent; color: var(--accent-ink); cursor: pointer;
  border: 1.5px solid var(--border-strong); font: inherit; font-weight: 600;
  text-decoration: none; clip-path: var(--clip-sm);
}
.btn-ghost:hover { border-color: var(--pop); color: var(--pop-deep); }

/* ---------- results + range bar ---------- */
.results {
  margin-top: var(--space-4);
  background: var(--accent-soft);
  border-top: 4px solid var(--accent);
  padding: var(--space-3) var(--space-4) var(--space-4);
}
.results h3 { margin: 0 0 var(--space-2); text-transform: uppercase; letter-spacing: 0.08em; font-size: var(--fs-sm); }
.result-row {
  display: flex; justify-content: space-between; align-items: baseline; gap: var(--space-3);
  padding: var(--space-2) 0; border-bottom: 1px dashed var(--border-strong);
}
.result-row:last-of-type { border-bottom: 0; }
.result-label { font-weight: 600; font-size: var(--fs-sm); }
.result-value { font-family: var(--font-display); font-weight: 700; text-align: right; }
.result-note { font-size: var(--fs-sm); color: var(--muted); }
.result-note p:last-child { margin-bottom: 0; }

.range-result { padding: var(--space-2) 0 var(--space-3); border-bottom: 1px dashed var(--border-strong); }
.range-result__head { display: flex; justify-content: space-between; align-items: baseline; gap: var(--space-3); }
.range-num {
  font-family: var(--font-display); font-weight: 800;
  font-size: var(--fs-3xl); color: var(--pop-deep); line-height: 1;
}
.range-bar { margin-top: var(--space-3); }
.range-track {
  position: relative; height: 14px;
  background: linear-gradient(90deg, #bcd6e6, #dcebf4);
  clip-path: polygon(0 0, calc(100% - 7px) 0, 100% 7px, 100% 100%, 7px 100%, 0 calc(100% - 7px));
}
.range-fill {
  position: absolute; top: 0; bottom: 0; left: 0; width: 0;
  background: var(--accent);
}
.range-marker {
  position: absolute; top: -5px; bottom: -5px; left: 0; width: 4px;
  background: var(--pop); transform: translateX(-2px);
}
.range-marker::after {
  content: ""; position: absolute; top: -6px; left: 50%; transform: translateX(-50%);
  border: 6px solid transparent; border-top: 7px solid var(--pop); border-bottom: 0;
}
.range-scale {
  display: flex; justify-content: space-between;
  font-size: var(--fs-xs); color: var(--muted); margin-top: var(--space-1);
  font-variant-numeric: tabular-nums;
}

/* ---------- how calculated / sections ---------- */
.how-calculated {
  background: var(--surface);
  border-left: 5px solid var(--pop);
  padding: var(--space-4);
}
.how-calculated h2 { margin-top: 0; }

/* ---------- tables ---------- */
.table-scroll { overflow-x: auto; margin-block: var(--space-3); -webkit-overflow-scrolling: touch; }
table { border-collapse: collapse; width: 100%; background: var(--card); }
th, td {
  padding: var(--space-2) var(--space-3); text-align: left;
  border-bottom: 1px solid var(--border); font-variant-numeric: tabular-nums;
}
thead th, table tr:first-child th[scope="col"] {
  background: var(--accent); color: var(--accent-contrast);
  font-family: var(--font-display); font-size: var(--fs-sm);
}
th[scope="row"] { font-weight: 700; background: var(--accent-soft); white-space: nowrap; }
.density-note { font-size: var(--fs-sm); color: var(--muted); }

/* chart band: full-bleed ice band, sticky first column, alternating rows */
.chart-band {
  background: linear-gradient(180deg, var(--surface), var(--accent-soft));
  padding: var(--space-5) 0;
  margin-block: var(--space-5);
  border-block: 3px solid var(--border-strong);
}
.chart-band h2 { margin-top: 0; }
/* Overflow guard: a wide chart table can never push past the band —
   it scrolls inside its wrapper instead (sticky first column intact). */
.chart-band .table-scroll { max-width: 100%; }
.chart-band table tr:nth-child(even) td { background: rgba(143, 193, 227, 0.14); }
.chart-band th[scope="row"] {
  position: sticky; left: 0; z-index: 1;
  background: var(--accent-soft);
  box-shadow: 2px 0 0 var(--border-strong);
}

/* ---------- tool cards ---------- */
.tool-grid {
  list-style: none; margin: 0; padding: 0;
  display: grid; gap: var(--space-3);
}
.tool-card {
  display: block; height: 100%;
  background: var(--card); color: var(--text); text-decoration: none;
  padding: var(--space-3) var(--space-4);
  clip-path: var(--clip-sm);
  border-left: 4px solid var(--accent);
  box-shadow: 0 4px 14px rgba(23, 56, 79, 0.1);
}
.tool-card strong { display: block; font-family: var(--font-display); font-size: var(--fs-lg); color: var(--accent-deep); }
.tool-card span { font-size: var(--fs-sm); color: var(--muted); }
.tool-card:hover { border-left-color: var(--pop); }
.tool-card:hover strong { color: var(--pop-deep); }
.home-link { margin-top: var(--space-3); }

/* ---------- FAQ ---------- */
.faq details {
  background: var(--card); margin-bottom: var(--space-2);
  border-left: 4px solid var(--border-strong);
  clip-path: polygon(0 0, calc(100% - 10px) 0, 100% 10px, 100% 100%, 0 100%);
}
.faq summary {
  cursor: pointer; font-weight: 700; font-family: var(--font-display);
  padding: var(--space-3); min-height: 44px;
}
.faq details p { padding: 0 var(--space-3) var(--space-3); margin: 0; }

/* ---------- sources ---------- */
.sources { font-size: var(--fs-sm); }
.sources ul { padding-left: 1.2rem; }
.last-verified { color: var(--muted); font-weight: 600; }
.report-line { font-size: var(--fs-sm); color: var(--muted); }

/* ---------- footer ---------- */
.site-footer {
  background-color: var(--navy-deep);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='480' height='240' viewBox='0 0 480 240'%3E%3Cg fill='none' stroke='%238fc1e3' stroke-opacity='0.13'%3E%3Cpath d='M-20 200 C80 140 160 220 260 170 S 420 120 500 160'/%3E%3Cpath d='M-20 170 C90 110 170 195 270 140 S 430 90 500 130'/%3E%3Cpath d='M-20 140 C100 80 180 165 280 110 S 440 60 500 100'/%3E%3Cpath d='M-20 110 C110 50 190 135 290 80 S 450 30 500 70'/%3E%3Cpath d='M-20 80 C120 20 200 105 300 50 S 460 5 500 40'/%3E%3C/g%3E%3C/svg%3E");
  background-repeat: repeat-x;
  background-position: bottom center;
  color: var(--navy-ink);
  margin-top: var(--space-6);
  padding-bottom: var(--space-4);
}
.footer-grid { display: grid; gap: var(--space-4); padding-top: var(--space-4); }
.site-footer h2 {
  color: #fff; font-size: var(--fs-base); text-transform: uppercase; letter-spacing: 0.1em;
}
.site-footer ul { list-style: none; margin: 0; padding: 0; }
.site-footer li { margin-bottom: var(--space-1); }
.site-footer a { color: var(--navy-muted); }
.site-footer a:hover { color: #fff; }
.footer-brand__name {
  display: flex; align-items: center; gap: var(--space-2);
  font-family: var(--font-display); font-weight: 700; font-size: var(--fs-lg); color: #fff;
  margin: 0 0 var(--space-2);
}
.footer-brand p { color: var(--navy-muted); font-size: var(--fs-sm); }
.footer-bottom { border-top: 1px solid rgba(143, 193, 227, 0.3); margin-top: var(--space-4); padding-top: var(--space-3); }
.footer-bottom p { color: var(--navy-muted); font-size: var(--fs-sm); margin: 0; }

/* ---------- breakpoints ---------- */
@media (min-width: 640px) {
  .field-grid { grid-template-columns: 1fr 1fr; }
  .tool-grid { grid-template-columns: 1fr 1fr; }
  .footer-grid { grid-template-columns: 1.4fr 1fr 1fr; }
}

@media (min-width: 1024px) {
  .tool-grid { grid-template-columns: 1fr 1fr 1fr; }
}

/* desktop nav layout */
@media (min-width: 768px) {
  .nav-toggle { display: none; }
  .site-nav__list {
    display: flex; flex-direction: row; position: static;
    background: none; box-shadow: none; padding: 0; min-width: 0;
    max-height: none; overflow: visible; align-items: center;
  }
  .has-dropdown ul {
    position: absolute; right: 0; top: calc(100% + 8px);
    background: var(--navy-deep); padding: var(--space-2);
    min-width: 17rem; max-height: calc(100dvh - 6rem); overflow-y: auto;
    box-shadow: var(--shadow);
  }
}

@media (max-width: 767px) {
  .site-logo { font-size: 1.05rem; }
  .page-head h1 { font-size: 1.8rem; }
  .hero { padding: var(--space-4) 0; }
  .hero h1 { font-size: 2.1rem; }
  .hero p { font-size: var(--fs-base); }
  .tool { padding: var(--space-3); }
  .range-result__head { flex-wrap: wrap; }
  th, td { padding: var(--space-1) var(--space-2); }
  .footer-grid li a { padding-block: 0.55rem; display: inline-block; }
  .btn-row .btn, .btn-row .btn-ghost { width: 100%; }
  .range-num { font-size: 1.7rem; }
  .results { padding: var(--space-3); }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; animation: none !important; }
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d1b26;
    --surface: #14303f;
    --card: #122a3a;
    --text: #e6f0f5;
    --muted: #9db8c6;
    --border: #274b61;
    --border-strong: #3f7095;
    --accent-ink: #dcebf4;
    --accent-soft: #173a4f;
    --pop-deep: #ff8a66;
    --shadow: 0 12px 30px rgba(0, 0, 0, 0.45);
  }
  .field input, .field select, .field textarea { background: #0d2233; color: var(--text); }
  .range-track { background: linear-gradient(90deg, #274b61, #173a4f); }
  .error-box { background: #3d1d1a; color: #f3c1bb; }
  thead th, table tr:first-child th[scope="col"] { background: #0f2739; }
  th[scope="row"] { background: #173a4f; }
  .chart-band th[scope="row"] { background: #173a4f; }
}