/* Hearthline Phase 1 — guidebook baseline */

:root{
  --bg:#fbfaf7;
  --paper:#ffffff;
  --text:#1f2328;
  --muted:#58636e;
  --line:rgba(31,35,40,.14);
  --soft:rgba(31,35,40,.06);

  --max: 74ch;
  --radius: 14px;

  --sans: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Apple Color Emoji","Segoe UI Emoji";
  --serif: ui-serif, "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;

  --s1: .65rem;
  --s2: 1.0rem;
  --s3: 1.6rem;
  --s4: 2.4rem;
  --s5: 3.2rem;

  --t-1: clamp(.95rem, .92rem + .2vw, 1.03rem);
  --t0:  clamp(1.06rem, 1.00rem + .3vw, 1.20rem);
  --t1:  clamp(1.28rem, 1.12rem + .8vw, 1.62rem);
  --t2:  clamp(1.60rem, 1.34rem + 1.2vw, 2.10rem);
  --t3:  clamp(2.05rem, 1.56rem + 2.2vw, 2.85rem);
}

*{ box-sizing:border-box; }
html,body{ height:100%; }
body{
  margin:0;
  background:var(--bg);
  color:var(--text);
  font-family:var(--serif);
  font-size:var(--t0);
  line-height:1.68;
  text-rendering:optimizeLegibility;
  -webkit-font-smoothing:antialiased;
}

.wrap{
  max-width: calc(var(--max) + 10rem);
  margin:0 auto;
  padding: var(--s4) var(--s3);
}

/* -------------------------------------------------
   Link treatment — Hearthline usability standard
------------------------------------------------- */

a{
  color: inherit;
  text-decoration: underline;
  text-decoration-thickness: .10em;
  text-underline-offset: .20em;
  text-decoration-color: rgba(31, 35, 40, 0.60);
}
a:hover,
a:focus-visible{
  text-decoration-color: rgba(31, 35, 40, 0.90);
}

/* All content links: always underlined */
.prose a,
.callout a,
.links a,
.card a,
.crumbs a {
  text-decoration: underline;
  text-decoration-thickness: 0.1em;
  text-underline-offset: 0.2em;
  text-decoration-color: rgba(31, 35, 40, 0.6);
}

/* Hover & focus: slightly stronger, not different */
.prose a:hover,
.callout a:hover,
.links a:hover,
.card a:hover,
.crumbs a:hover,
.prose a:focus-visible,
.callout a:focus-visible,
.links a:focus-visible,
.card a:focus-visible,
.crumbs a:focus-visible {
  text-decoration-color: rgba(31, 35, 40, 0.9);
}

/* Top navigation & brand stay clean */
.brand a,
.nav {
  text-decoration: none;
}

.skip{
  position:absolute;
  left:-999px;
  top:auto;
  width:1px;
  height:1px;
  overflow:hidden;
}
.skip:focus{
  left: var(--s3);
  top: var(--s3);
  width:auto;
  height:auto;
  padding: .5rem .75rem;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 10px;
}

header.site{
  background: transparent;
  border-bottom: 1px solid var(--line);
}
.brandrow{
  display:flex;
  align-items:baseline;
  justify-content:space-between;
  gap: var(--s3);
}
.brand{
  font-family:var(--sans);
  font-weight:650;
  letter-spacing:.02em;
  font-size:var(--t1);
  text-decoration: underline;
}
.nav{
  display:flex;
  gap: var(--s2);
  font-family:var(--sans);
  font-size:var(--t-1);
  color:var(--muted);
}
.nav a{
  text-decoration: underline;
  padding:.35rem .55rem;
  border-radius:10px;
}
.nav a:hover{ background: var(--soft); }

.crumbs{
  font-family:var(--sans);
  font-size:var(--t-1);
  color:var(--muted);
  margin: 0 0 var(--s3);
}
.crumbs a{ text-decoration: underline; }
.crumbs span{ margin:0 .35rem; }

.prose{
  max-width: var(--max);
}

.articlehead h1{
  margin: 0 0 var(--s2);
  font-size: var(--t3);
  line-height: 1.12;
  letter-spacing:-.01em;
}
.lede{
  margin: 0 0 var(--s3);
  color: var(--muted);
  font-size: var(--t1);
  line-height: 1.55;
}

.cardlist{
  display:grid;
  gap: var(--s3);
}
.card{
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: var(--s3);
}
.card h3 a{
  text-decoration: underline;
  text-decoration-thickness: 0.12em;
}
.card h3 a:hover{
  text-decoration: underline;
}

.meta{
  display:grid;
  grid-template-columns: 1fr;
  gap: .75rem;
  margin: 0 0 var(--s4);
  padding: var(--s3);
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-family: var(--sans);
  font-size: var(--t-1);
  color: var(--muted);
}
.meta div{ display:flex; gap:.6rem; }
.meta dt{
  min-width: 5.5rem;
  color: rgba(88,99,110,.9);
}
.meta dd{
  margin:0;
  color: var(--text);
}

h2{
  margin: var(--s5) 0 var(--s2);
  font-size: var(--t2);
  line-height: 1.18;
  letter-spacing:-.01em;
}
h3{
  margin: var(--s4) 0 var(--s1);
  font-size: var(--t1);
  line-height: 1.22;
}

p{ margin: 0 0 var(--s3); }

ul,ol{
  margin: 0 0 var(--s3);
  padding-left: 1.2rem;
}
li{ margin: .35rem 0; }

hr{
  border:0;
  border-top:1px solid var(--line);
  margin: var(--s5) 0;
}

.callout{
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: var(--s3);
}
.callout h2{ margin-top:0; }
.links{ margin: 0; font-family: var(--sans); font-size: var(--t-1); color: var(--muted); }
.links a{ text-decoration: underline; }

.sitefoot{
  border-top: 1px solid var(--line);
  margin-top: var(--s5);
  padding: var(--s4) 0;
  color: var(--muted);
  font-family: var(--sans);
  font-size: var(--t-1);
  text-align: center;
}

/* Responsive polish */
@media (min-width: 880px){
  .meta{ grid-template-columns: 1fr 1fr; }
}

/* Print-friendly */
@media print{
  :root{ --bg:#ffffff; --paper:#ffffff; --line:#cccccc; }
  body{ background:#ffffff; }
  header.site, .sitefoot, .nav, .crumbs, .callout { display:none; }
  .wrap{ max-width: 100%; padding: 0; }
  a{ text-decoration:none; }
  .meta{ border:1px solid #cccccc; }
}

/* === Link visibility guardrail (keep at bottom) === */
main a:not(.btn):not(.button) {
  text-decoration: underline !important;
  text-decoration-thickness: 0.10em !important;
  text-underline-offset: 0.20em !important;
  text-decoration-color: rgba(31,35,40,0.70) !important;
}

/* Keep top nav and brand clean */
header.site .nav a,
header.site .brand {
  text-decoration: none !important;
}