/* ==========================================================================
   MobilityCharts site stylesheet
   One accent colour plus greys, per SOP-03 visual standard.
   No external fonts, no external assets. Works offline.
   ========================================================================== */

:root {
  --bg:        #FBFAF7;
  --surface:   #FFFFFF;
  --surface-2: #F3F2EE;
  --ink:       #14181C;
  --ink-soft:  #4A555E;
  --muted:     #78838C;
  --line:      #E3E2DC;
  --line-soft: #EFEEE9;
  --accent:    #0E7A6B;
  --accent-2:  #B8663A;
  --bar:       #0E7A6B;
  --bar-alt:   #7FB3AA;
  --shadow:    0 1px 2px rgba(20, 24, 28, .05), 0 8px 24px rgba(20, 24, 28, .05);

  --serif: Georgia, "Iowan Old Style", "Times New Roman", serif;
  --sans:  system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --mono:  "Cascadia Mono", Consolas, "SF Mono", Menlo, monospace;

  --wrap: 940px;
  --r: 10px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg:        #0D1113;
    --surface:   #151A1D;
    --surface-2: #1C2226;
    --ink:       #ECEFF0;
    --ink-soft:  #B4BDC3;
    --muted:     #8B959C;
    --line:      #232A2E;
    --line-soft: #1B2125;
    --accent:    #35C2A8;
    --accent-2:  #E0904F;
    --bar:       #35C2A8;
    --bar-alt:   #2A6B62;
    --shadow:    0 1px 2px rgba(0, 0, 0, .4), 0 8px 24px rgba(0, 0, 0, .3);
  }
}

:root[data-theme="light"] {
  --bg:#FBFAF7; --surface:#FFFFFF; --surface-2:#F3F2EE; --ink:#14181C;
  --ink-soft:#4A555E; --muted:#78838C; --line:#E3E2DC; --line-soft:#EFEEE9;
  --accent:#0E7A6B; --accent-2:#B8663A; --bar:#0E7A6B; --bar-alt:#7FB3AA;
  --shadow: 0 1px 2px rgba(20,24,28,.05), 0 8px 24px rgba(20,24,28,.05);
}
:root[data-theme="dark"] {
  --bg:#0D1113; --surface:#151A1D; --surface-2:#1C2226; --ink:#ECEFF0;
  --ink-soft:#B4BDC3; --muted:#8B959C; --line:#232A2E; --line-soft:#1B2125;
  --accent:#35C2A8; --accent-2:#E0904F; --bar:#35C2A8; --bar-alt:#2A6B62;
  --shadow: 0 1px 2px rgba(0,0,0,.4), 0 8px 24px rgba(0,0,0,.3);
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.65;
  letter-spacing: -0.003em;
}

a { color: var(--accent); text-decoration-thickness: 1px; text-underline-offset: 2px; }
a:hover { color: var(--ink); }

:focus-visible { box-shadow: 0 0 0 3px var(--accent); border-radius: 4px; }

.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 22px; }

/* ---------- masthead ---------------------------------------------------- */

.masthead {
  border-bottom: 1px solid var(--line);
  background: var(--surface);
  position: sticky; top: 0; z-index: 20;
}
.masthead .wrap {
  display: flex; align-items: center; gap: 18px;
  min-height: 62px; flex-wrap: wrap;
}
.brand {
  font-family: var(--serif);
  font-size: 21px; font-weight: 700; letter-spacing: -0.02em;
  color: var(--ink); text-decoration: none; margin-right: auto;
  display: inline-flex; align-items: center; gap: 9px;
}
.brand .glyph {
  display: inline-block; width: 20px; height: 20px;
  background:
    linear-gradient(var(--accent), var(--accent)) 0 100% / 4px 9px no-repeat,
    linear-gradient(var(--accent), var(--accent)) 8px 100% / 4px 17px no-repeat,
    linear-gradient(var(--accent), var(--accent)) 16px 100% / 4px 13px no-repeat;
}
.nav { display: flex; gap: 20px; align-items: center; }
.nav a {
  color: var(--ink-soft); text-decoration: none;
  font-size: 14.5px; font-weight: 500;
}
.nav a:hover, .nav a[aria-current="page"] { color: var(--accent); }

.theme-btn {
  background: var(--surface-2); color: var(--ink-soft);
  border: 1px solid var(--line); border-radius: 999px;
  padding: 5px 13px; font: inherit; font-size: 13px; cursor: pointer;
}
.theme-btn:hover { color: var(--ink); border-color: var(--muted); }

/* ---------- notice banner ----------------------------------------------- */

.notice {
  background: var(--surface-2);
  border-bottom: 1px solid var(--line);
  font-size: 13.5px; color: var(--ink-soft);
  padding: 9px 0;
}
.notice strong { color: var(--accent-2); }

/* ---------- hero -------------------------------------------------------- */

.hero { padding: 62px 0 40px; border-bottom: 1px solid var(--line); }
.hero h1 {
  font-family: var(--serif); font-weight: 700;
  font-size: clamp(34px, 5.4vw, 54px); line-height: 1.08;
  letter-spacing: -0.025em; margin: 0 0 18px; max-width: 17ch;
}
.hero p { font-size: 19px; color: var(--ink-soft); max-width: 58ch; margin: 0 0 26px; }
.hero .kicker {
  font-size: 12.5px; font-weight: 600; letter-spacing: .14em;
  text-transform: uppercase; color: var(--accent); margin: 0 0 16px;
}

.btn {
  display: inline-block; background: var(--accent); color: #fff;
  padding: 11px 22px; border-radius: 999px; text-decoration: none;
  font-size: 15px; font-weight: 600; border: 1px solid var(--accent);
}
.btn:hover { filter: brightness(1.08); color: #fff; }
.btn.ghost { background: transparent; color: var(--ink); border-color: var(--line); }
.btn.ghost:hover { border-color: var(--accent); color: var(--accent); filter: none; }

/* ---------- section scaffolding ----------------------------------------- */

section { padding: 52px 0; }
.sec-head { display: flex; align-items: baseline; gap: 14px; margin-bottom: 26px; }
.sec-head h2 {
  font-family: var(--serif); font-size: 27px; letter-spacing: -0.02em;
  margin: 0; font-weight: 700;
}
.sec-head .rule { flex: 1; height: 1px; background: var(--line); }
.sec-head .count { font-size: 13px; color: var(--muted); font-variant-numeric: tabular-nums; }

/* ---------- cards ------------------------------------------------------- */

.grid { display: grid; gap: 18px; grid-template-columns: repeat(auto-fill, minmax(268px, 1fr)); }

.card {
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--r); padding: 20px; text-decoration: none;
  color: var(--ink); display: block; transition: border-color .15s, transform .15s;
}
.card:hover { border-color: var(--accent); transform: translateY(-2px); color: var(--ink); }
.card .tag {
  font-size: 11.5px; font-weight: 600; letter-spacing: .1em; text-transform: uppercase;
  color: var(--accent); display: block; margin-bottom: 9px;
}
.card h3 { font-family: var(--serif); font-size: 19px; margin: 0 0 8px; line-height: 1.28; font-weight: 700; }
.card p { margin: 0; font-size: 14.5px; color: var(--ink-soft); line-height: 1.5; }
.card .meta { margin-top: 13px; font-size: 12.5px; color: var(--muted); font-variant-numeric: tabular-nums; }

/* ---------- chart page -------------------------------------------------- */

.article { padding: 46px 0 20px; }
.article h1 {
  font-family: var(--serif); font-size: clamp(29px, 4.4vw, 42px);
  line-height: 1.14; letter-spacing: -0.024em; margin: 0 0 16px; max-width: 21ch;
}
.dek { font-size: 19.5px; color: var(--ink-soft); margin: 0 0 22px; max-width: 60ch; }
.dek b { color: var(--ink); font-weight: 600; }

.byline {
  display: flex; gap: 16px; flex-wrap: wrap; align-items: center;
  font-size: 13px; color: var(--muted); padding-bottom: 22px;
  border-bottom: 1px solid var(--line); margin-bottom: 30px;
}
.byline .pill {
  background: var(--surface-2); border: 1px solid var(--line);
  border-radius: 999px; padding: 3px 11px; color: var(--ink-soft);
}

.chart-frame {
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--r); padding: 22px 20px 14px; box-shadow: var(--shadow);
}
.chart-frame + .chart-frame { margin-top: 26px; }
.chart-title {
  font-family: var(--serif); font-size: 20px; font-weight: 700;
  margin: 0 0 4px; letter-spacing: -0.015em;
}
.chart-sub { font-size: 13.5px; color: var(--muted); margin: 0 0 16px; }

.takeaways { list-style: none; padding: 0; margin: 32px 0 0; }
.takeaways li {
  padding: 13px 0 13px 40px; border-top: 1px solid var(--line-soft);
  position: relative; font-size: 16.5px; color: var(--ink-soft);
}
.takeaways li:last-child { border-bottom: 1px solid var(--line-soft); }
.takeaways li b { color: var(--ink); font-weight: 650; font-variant-numeric: tabular-nums; }
.takeaways li::before {
  counter-increment: tk; content: counter(tk, decimal-leading-zero);
  position: absolute; left: 0; top: 13px;
  font-family: var(--mono); font-size: 12.5px; color: var(--accent); font-weight: 600;
}
.takeaways { counter-reset: tk; }

/* ---------- data table -------------------------------------------------- */

table.data { width: 100%; border-collapse: collapse; margin-top: 10px; font-size: 15px; }
table.data th, table.data td { padding: 10px 12px; text-align: left; border-bottom: 1px solid var(--line-soft); }
table.data th {
  font-size: 12px; letter-spacing: .09em; text-transform: uppercase;
  color: var(--muted); font-weight: 600; border-bottom-color: var(--line);
  cursor: pointer; user-select: none;
}
table.data th:hover { color: var(--accent); }
table.data th.num, table.data td.num { text-align: right; font-variant-numeric: tabular-nums; }
table.data tbody tr:hover { background: var(--surface-2); }

/* ---------- method note, embed box -------------------------------------- */

.panel {
  background: var(--surface-2); border: 1px solid var(--line);
  border-radius: var(--r); padding: 20px 22px; margin-top: 30px;
}
.panel h3 {
  font-size: 12px; letter-spacing: .12em; text-transform: uppercase;
  color: var(--muted); margin: 0 0 12px; font-weight: 600;
}
.panel dl { margin: 0; display: grid; grid-template-columns: 150px 1fr; gap: 7px 18px; font-size: 14.5px; }
.panel dt { color: var(--muted); }
.panel dd { margin: 0; color: var(--ink-soft); }

.embed-box code {
  display: block; background: var(--surface); border: 1px solid var(--line);
  border-radius: 7px; padding: 13px 15px; font-family: var(--mono);
  font-size: 12.5px; color: var(--ink-soft); line-height: 1.55;
  word-break: break-all; margin-bottom: 12px;
}
.copy-btn {
  background: var(--accent); color: #fff; border: 0; border-radius: 999px;
  padding: 8px 18px; font: inherit; font-size: 14px; font-weight: 600; cursor: pointer;
}
.copy-btn:hover { filter: brightness(1.08); }
.copy-btn.done { background: var(--accent-2); }

/* ---------- subscribe --------------------------------------------------- */

.subscribe {
  background: var(--surface); border: 1px solid var(--line);
  border-left: 3px solid var(--accent); border-radius: var(--r);
  padding: 26px 24px; margin-top: 34px;
}
.subscribe h3 { font-family: var(--serif); font-size: 21px; margin: 0 0 7px; font-weight: 700; }
.subscribe p { margin: 0 0 16px; color: var(--ink-soft); font-size: 15.5px; }
.sub-row { display: flex; gap: 9px; flex-wrap: wrap; }
.sub-row input {
  flex: 1 1 240px; background: var(--bg); border: 1px solid var(--line);
  border-radius: 999px; padding: 10px 17px; font: inherit; font-size: 15px; color: var(--ink);
}
.sub-row input::placeholder { color: var(--muted); }

/* ---------- footer ------------------------------------------------------ */

footer { border-top: 1px solid var(--line); margin-top: 60px; padding: 36px 0 54px; }
.foot-grid { display: grid; gap: 26px; grid-template-columns: repeat(auto-fit, minmax(170px, 1fr)); }
.foot-grid h4 {
  font-size: 11.5px; letter-spacing: .12em; text-transform: uppercase;
  color: var(--muted); margin: 0 0 11px; font-weight: 600;
}
.foot-grid ul { list-style: none; padding: 0; margin: 0; }
.foot-grid li { margin-bottom: 7px; }
.foot-grid a { color: var(--ink-soft); text-decoration: none; font-size: 14.5px; }
.foot-grid a:hover { color: var(--accent); }
.colophon {
  margin-top: 30px; padding-top: 20px; border-top: 1px solid var(--line-soft);
  font-size: 13px; color: var(--muted); display: flex; gap: 16px; flex-wrap: wrap;
}

/* ---------- SVG chart styling (classes set by chart.js) ----------------- */

.mc-svg { width: 100%; height: auto; display: block; margin: 0 auto; font-family: var(--sans); }
.mc-bar { fill: var(--bar); }
.mc-bar.alt { fill: var(--bar-alt); }
.mc-track { fill: var(--line-soft); }
.mc-grid { stroke: var(--line); stroke-width: 1; }
.mc-axis { stroke: var(--muted); stroke-width: 1; }
.mc-line { fill: none; stroke: var(--bar); stroke-width: 2.5; stroke-linejoin: round; stroke-linecap: round; }
.mc-fill { fill: var(--bar); opacity: .1; }
.mc-dot { fill: var(--bar); }
.mc-label { fill: var(--ink-soft); font-size: 13px; }
.mc-value { fill: var(--ink); font-size: 13px; font-weight: 650; }
.mc-tick { fill: var(--muted); font-size: 11.5px; }
.mc-credit { fill: var(--muted); font-size: 11px; }
.mc-mark { fill: var(--muted); font-size: 11px; opacity: .75; letter-spacing: .04em; }
.mc-unit { fill: var(--muted); font-size: 11.5px; letter-spacing: .08em; text-transform: uppercase; }

/* ---------- small screens ----------------------------------------------- */

@media (max-width: 640px) {
  body { font-size: 16px; }
  .nav { gap: 14px; }
  .nav a { font-size: 13.5px; }
  .hero { padding: 44px 0 32px; }
  .panel dl { grid-template-columns: 1fr; gap: 2px 0; }
  .panel dt { margin-top: 9px; font-size: 12.5px; }
  .mc-label { font-size: 12px; }
  .mc-value { font-size: 12px; }
}

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