:root{
  --bg:#f6f7fb;
  --card:#ffffff;
  --text:#111827;
  --muted:#6b7280;
  --border:#e5e7eb;
  --accent:#2563eb;
  --radius:14px;
  --shadow:0 10px 28px rgba(0,0,0,.06);
}

*{box-sizing:border-box}
html,body{height:100%}
body{
  margin:0;
  font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,"Noto Sans",sans-serif;
  background:var(--bg);
  color:var(--text);
}

a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}

.container{
  max-width:1100px;
  margin:0 auto;
  padding:18px 18px 46px;
}

/* Header */
.header{
  position:sticky;
  top:0;
  z-index:50;
  background:rgba(246,247,251,.86);
  backdrop-filter:saturate(1.2) blur(10px);
  border-bottom:1px solid rgba(229,231,235,.7);
}
.header-inner{
  max-width:1100px;
  margin:0 auto;
  padding:14px 18px;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:14px;
}
.brand{
  display:flex;
  align-items:center;
  gap:10px;
  min-width:190px;
}
.logo{
  width:34px;height:34px;
  border-radius:12px;
  display:grid;
  place-items:center;
  font-weight:800;
  color:#fff;
  background:var(--text);
}
.logo svg{ width:18px; height:18px; display:block; color:#fff; }

/* Root以外で出てしまう "Fast, simple, private" を消す */
.tagline{ display:none; }

.badge{
  display:inline-block;
  margin-left:8px;
  font-size:12px;
  padding:2px 8px;
  border-radius:999px;
  border:1px solid var(--border);
  color:var(--muted);
  background:#fff;
}
.nav{
  display:flex;
  gap:14px;
  align-items:center;
  flex-wrap:wrap;
  justify-content:flex-end;
}
.nav a{
  color:var(--muted);
  font-weight:600;
  text-decoration:none;
}
.nav a:hover{color:var(--text)}

/* Mobile menu button */
.menu-btn{
  display:none;
  align-items:center;
  justify-content:center;
  width:44px;
  height:44px;
  border-radius:14px;
  border:1px solid var(--border);
  background:#fff;
  color:var(--text);
  cursor:pointer;
}
.menu-btn svg{width:18px;height:18px}

/* Layout: Sidebar + Main */
.layout{
  display:grid;
  grid-template-columns: 260px minmax(0, 1fr);
  gap:16px;
  align-items:start;
}
@media (max-width: 900px){
  .layout{grid-template-columns:220px minmax(0,1fr); gap:12px;}
}
@media (max-width: 720px){
  .layout{grid-template-columns:200px minmax(0,1fr); gap:10px;}
}

/* Sidebar (desktop/tablet) */
.sidebar{
  position: sticky;
  top: 88px;
  max-height: calc(100vh - 88px - 18px);
  overflow: auto;
}
.main{min-width:0}

/* ===== Drawer (420px and below) ===== */
@media (max-width: 420px){
  .nav{display:none}
  .menu-btn{display:inline-flex}

  .layout{grid-template-columns: 1fr;}

  /* hidden by default, shown only when body.sidebar-open */
  .sidebar{
    position: fixed;
    top: 0;
    left: 0;
    height: 100vh;
    width: min(88vw, 360px);
    max-height: none;
    overflow: auto;
    transform: translateX(-110%);
    transition: transform .18s ease;
    z-index: 200;
    padding: 14px;
    background: var(--bg);
    box-shadow: var(--shadow);
  }
  body.sidebar-open .sidebar{
    transform: translateX(0);
  }

  /* overlay */
  .sidebar-overlay{
    position: fixed;
    inset: 0;
    background: rgba(17,24,39,.42);
    opacity: 0;
    pointer-events: none;
    transition: opacity .18s ease;
    z-index: 150;
  }
  body.sidebar-open .sidebar-overlay{
    opacity: 1;
    pointer-events: auto;
  }

  body.sidebar-open{ overflow: hidden; }
}

.cat-list{
  display:grid;
  gap:10px;
  margin-top:10px;
}
.cat{
  display:flex;
  justify-content:space-between;
  align-items:center;
  padding:10px 12px;
  border-radius:12px;
  border:1px solid var(--border);
  background:#fff;
  font-weight:800;
  color:var(--text);
}
.cat:hover{background:#f9fafb;text-decoration:none}
.cat small{
  color:var(--muted);
  font-weight:700;
}

.card{
  background:var(--card);
  border:1px solid rgba(229,231,235,.85);
  border-radius:var(--radius);
  box-shadow:var(--shadow);
  padding:18px;
}
.hero{
  padding:26px;
  border-radius:18px;
  border:1px solid rgba(229,231,235,.8);
  background:linear-gradient(180deg,#ffffff 0%, #fbfbfe 100%);
  box-shadow:var(--shadow);
}
.hero h1{
  font-size:44px;
  letter-spacing:-.02em;
  margin:0 0 8px;
}
.hero p{
  margin:0;
  color:var(--muted);
  line-height:1.6;
  max-width:62ch;
}
.note{
  margin-top:14px;
  padding:10px 12px;
  border-radius:12px;
  border:1px dashed rgba(229,231,235,.9);
  color:var(--muted);
  background:#fff;
}

.section-title{
  display:flex;
  align-items:baseline;
  justify-content:space-between;
  gap:10px;
  margin-bottom:12px;
}
.section-title h2{
  margin:0;
  font-size:20px;
  letter-spacing:-.01em;
}
.hint{
  color:var(--muted);
  font-weight:700;
  font-size:13px;
}

.grid{
  margin-top:16px;
  display:grid;
  gap:16px;
}
.tool-list{display:grid; gap:12px;}
.tool{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:12px;
  padding:14px;
  border-radius:14px;
  border:1px solid var(--border);
  background:#fff;
}
.tool .left{min-width:0}
.name{margin:0; font-weight:800}
.desc{margin:6px 0 0; color:var(--muted)}
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  min-width:74px;
  padding:10px 16px;
  border-radius:999px;
  border:1px solid var(--border);
  font-weight:800;
  text-decoration:none !important;
  color:var(--text);
  background:#fff;
}
.btn.primary{
  background:var(--accent);
  color:#fff;
  border-color:transparent;
}
.btn.disabled{
  color:var(--muted);
  background:#f3f4f6;
  border-color:#e5e7eb;
  cursor:not-allowed;
}

.breadcrumbs{
  color:var(--muted);
  font-weight:700;
  font-size:13px;
  margin-bottom:10px;
}
.ad-slot{
  height:140px;
  border-radius:14px;
  border:1px dashed rgba(229,231,235,.9);
  display:flex;
  align-items:center;
  justify-content:center;
  color:var(--muted);
  background:#fff;
}