*{margin:0;padding:0;box-sizing:border-box}
:root{--bg:#f8f9fa;--surface:#ffffff;--border:#e2e8f0;--text:#1a202c;--text-muted:#64748b;--accent:#2563eb;--accent-light:#eff6ff;--accent-grad:linear-gradient(135deg,#2563eb,#7c3aed);--tag-bg:#f1f5f9;--tag-border:#e2e8f0;--card-shadow:0 1px 3px rgba(0,0,0,.06),0 1px 2px rgba(0,0,0,.04);--card-hover-shadow:0 4px 12px rgba(0,0,0,.08)}
body{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,'Helvetica Neue',Arial,sans-serif;background:var(--bg);color:var(--text);line-height:1.7;-webkit-font-smoothing:antialiased}
.container{max-width:780px;margin:0 auto;padding:2rem 1.5rem}
header{text-align:center;padding:2.5rem 0 1.5rem;border-bottom:1px solid var(--border);margin-bottom:2rem}
header h1{font-size:clamp(1.3rem,4vw,1.8rem);background:var(--accent-grad);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
header .sub{color:var(--text-muted);font-size:.85rem;margin-top:.3rem}
nav{display:flex;justify-content:center;gap:1.2rem;margin-top:.7rem;flex-wrap:wrap}
nav a{color:var(--accent);text-decoration:none;font-size:.85rem;font-weight:500;padding:.2rem .4rem;border-radius:4px;transition:background .15s}
nav a:hover{background:var(--accent-light);text-decoration:none}
section{margin-bottom:2.5rem}
h2{font-size:1.15rem;color:var(--text);margin-bottom:1rem;display:flex;align-items:center;gap:.5rem;font-weight:600;padding-bottom:.4rem;border-bottom:2px solid var(--accent-light)}
.card{background:var(--surface);border:1px solid var(--border);border-radius:10px;padding:1.1rem;margin-bottom:.9rem;box-shadow:var(--card-shadow);transition:box-shadow .2s,border-color .2s}
.card:hover{box-shadow:var(--card-hover-shadow);border-color:var(--accent)}
.card h3{font-size:.95rem;color:var(--text);margin-bottom:.25rem;font-weight:600}
.card .meta{font-size:.78rem;color:var(--text-muted);margin-bottom:.35rem}
.card .desc{font-size:.85rem;color:var(--text-muted);margin:.45rem 0;line-height:1.6}
.tags{display:flex;gap:.35rem;flex-wrap:wrap;margin:.4rem 0}
.tag{background:var(--tag-bg);color:var(--accent);font-size:.72rem;padding:.12rem .45rem;border-radius:5px;border:1px solid var(--tag-border);font-weight:500}
.link{color:var(--accent);text-decoration:none;font-size:.82rem;font-weight:500;display:inline-flex;align-items:center;gap:.3rem}
.link:hover{text-decoration:underline}
.news-item{background:var(--surface);border-left:3px solid var(--accent);padding:.65rem 1rem;margin-bottom:.55rem;border-radius:0 6px 6px 0;font-size:.88rem;box-shadow:var(--card-shadow)}
.news-title{font-weight:500;color:var(--text);margin-bottom:.1rem}
.news-summary{font-size:.82rem;color:var(--text-muted);margin:.25rem 0;line-height:1.5}
.news-link{color:var(--accent);text-decoration:none;font-size:.78rem;font-weight:500;display:inline-block;margin-top:.15rem}
.news-link:hover{text-decoration:underline}
.why-badge{font-size:.82rem;color:#6d28d9;background:#f5f3ff;border:1px solid #ede9fe;border-radius:6px;padding:.35rem .6rem;margin:.4rem 0;line-height:1.4}
.news-item .src{font-size:.78rem;color:var(--text-muted);margin-top:.15rem}
.concept-item{background:var(--surface);border:1px solid var(--border);border-radius:8px;padding:.75rem 1rem;margin-bottom:.7rem;box-shadow:var(--card-shadow)}
.concept-item strong{color:var(--text);font-size:.9rem}
.concept-item .why{font-size:.82rem;color:var(--text-muted);margin-top:.2rem;line-height:1.5}
.learning-path{background:var(--surface);border:1px solid var(--border);border-radius:12px;padding:1.3rem;box-shadow:var(--card-shadow)}
.learning-path h3{font-size:.95rem;color:var(--accent);margin-bottom:.6rem}
.learning-path ol{padding-left:1.1rem}
.learning-path li{margin-bottom:.4rem;color:var(--text-muted);font-size:.85rem;line-height:1.5}
.learning-path li strong{color:var(--text)}
.blank{color:var(--text-muted);text-align:center;padding:2.5rem;font-size:.9rem}
.archive-list{background:var(--surface);border:1px solid var(--border);border-radius:10px;overflow:hidden;box-shadow:var(--card-shadow)}
.archive-item{display:flex;justify-content:space-between;align-items:center;padding:.75rem 1rem;border-bottom:1px solid var(--border);transition:background .15s}
.archive-item:last-child{border-bottom:0}
.archive-item:hover{background:var(--accent-light)}
.archive-item .date{color:var(--text);font-size:.88rem;font-weight:500}
.archive-item .status{font-size:.78rem;color:var(--text-muted)}
footer{text-align:center;padding:1.8rem;border-top:1px solid var(--border);color:var(--text-muted);font-size:.78rem;margin-top:1rem}
@media(max-width:640px){
  .container{padding:1rem .85rem}
  header{padding:1.8rem 0 1rem}
  header h1{font-size:1.15rem}
  .card{padding:.85rem .85rem}
  .card h3{font-size:.88rem}
  .news-item{padding:.5rem .75rem;font-size:.82rem}
  .tags{gap:.25rem}
  .tag{font-size:.68rem;padding:.1rem .35rem}
  .archive-item{padding:.6rem .8rem;flex-direction:column;align-items:flex-start;gap:.15rem}
  .learning-path{padding:1rem}
  section{margin-bottom:1.8rem}
}
@media(max-width:400px){
  .container{padding:.7rem .6rem}
  nav{gap:.8rem}
  nav a{font-size:.8rem}
  .card .desc{font-size:.8rem}
}