/* =========================================
   programming/css/main.css
   ========================================= */

:root{
  --bg: #0b0f14;
  --card: #101720;
  --ink: #e9f1ff;
  --muted: #a9b7c6;
  --brand: #61dafb;   /* さりげないテック感 */
  --accent: #9dffa9;  /* 視認性の高い緑アクセント */
  --line: #1d2733;
}

* { box-sizing: border-box; }
html, body { margin:0; padding:0; }
body{
  background: linear-gradient(180deg, #0a0e13, #0b1119 40%, #0a0f16);
  color: var(--ink);
  font-family: system-ui, -apple-system, "Segoe UI", "Hiragino Kaku Gothic ProN", Roboto, "Noto Sans JP", sans-serif;
  line-height: 1.8;
}

.container{
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 20px;
}

.site-header{
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(11,15,20,0.8);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--line);
}
.header-inner{
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 14px 0;
}
.site-header h1{
  font-size: 20px;
  margin: 0;
  letter-spacing: 0.02em;
}
.global-nav{
  margin-left: auto;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 16px;
}
.global-nav a{
  color: var(--muted);
  text-decoration: none;
  padding: 6px 10px;
  border-radius: 10px;
  transition: 150ms;
}
.global-nav a:hover{
  color: var(--ink);
  background: #0d1620;
}

main.container{
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 20px;
  padding: 26px 20px 80px;
}
@media (max-width: 980px){
  main.container{
    grid-template-columns: 1fr;
  }
}

/* TOC */
.toc{
  position: sticky;
  top: 74px;
  align-self: start;
  background: #0d141c;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 14px 14px 8px;
}
.toc h2{
  margin: 0 0 8px;
  font-size: 14px;
  color: var(--muted);
}
.toc ul{ list-style: none; padding: 0; margin: 0; }
.toc a{
  display: block;
  color: var(--muted);
  text-decoration: none;
  padding: 6px 8px;
  border-radius: 8px;
  margin: 2px 0;
  transition: 150ms;
}
.toc a:hover{ background: #0f1924; color: var(--ink); }
.toc a.active{ background: #112133; color: var(--accent); }

/* Cards */
.card{
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 20px 22px;
  box-shadow: 0 6px 24px rgba(0,0,0,0.25);
}
.card h2{
  margin-top: 0;
  border-left: 4px solid var(--brand);
  padding-left: 10px;
}

.checklist{ margin: 0; padding-left: 1.1em; }
.checklist li{ margin: 6px 0; }

.grid-2{
  display: grid;
  gap: 8px 18px;
  grid-template-columns: repeat(2, minmax(0,1fr));
  padding-left: 0;
  list-style: none;
}
@media (max-width: 640px){
  .grid-2{ grid-template-columns: 1fr; }
}

/* Updates */
.updates{
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}
.updates li{
  display: flex;
  gap: 14px;
  align-items: baseline;
  border-left: 2px solid #183146;
  padding-left: 12px;
}
.updates time{
  color: var(--muted);
  font-size: 0.92em;
}

/* Sitemap area */
.sitemap-controls{
  display: flex;
  gap: 10px;
  margin-bottom: 10px;
  flex-wrap: wrap;
}
.sitemap-controls input[type="search"]{
  flex: 1 1 320px;
  background: #0e1721;
  border: 1px solid var(--line);
  border-radius: 10px;
  color: var(--ink);
  padding: 10px 12px;
}
.sitemap-controls button{
  background: #102131;
  border: 1px solid var(--line);
  border-radius: 10px;
  color: var(--ink);
  padding: 10px 12px;
  cursor: pointer;
}
.sitemap-controls button:hover{
  background: #15283b;
}

.sitemap{
  border: 1px dashed #1c2a3a;
  border-radius: 14px;
  padding: 12px 14px;
}
.sitemap > summary{
  list-style: none;
  cursor: pointer;
}
.sitemap > summary::-webkit-details-marker{ display: none; }
.sitemap > summary h3{
  display: inline-block;
  margin: 0 8px 0 0;
}
.sitemap > summary p{
  display: inline;
  color: var(--muted);
}

.sitemap-list{
  columns: 2 360px;
  column-gap: 28px;
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
}
.sitemap-list li{
  break-inside: avoid;
  margin: 4px 0;
}
.sitemap-list li.cat{
  margin: 12px 0 6px;
  font-weight: 700;
  color: var(--accent);
}
.sitemap-list a{
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px dashed #23354a;
}
.sitemap-list a:hover{
  border-bottom-color: var(--brand);
  color: var(--brand);
}

/* Links */
.links{ list-style: none; margin: 0; padding: 0; display: grid; gap: 6px; }
.links a{ color: var(--brand); text-decoration: none; }
.links a:hover{ text-decoration: underline; }

/* Footer */
.site-footer{
  border-top: 1px solid var(--line);
  background: #0a1016;
  padding: 16px 0 30px;
}
.site-footer .container{
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}
.footer-nav a{
  color: var(--muted);
  text-decoration: none;
}
.footer-nav a:hover{ color: var(--ink); }
.to-top{
  padding: 6px 10px;
  border: 1px solid var(--line);
  border-radius: 10px;
}