:root {
  --ink: #1b2733;
  --muted: #5c6b7a;
  --line: #e3e8ee;
  --accent: #0a7a63;
  --accent-ink: #ffffff;
  --bg: #ffffff;
  --chip: #eef3f6;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.55;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.9rem 1.4rem;
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(6px);
  z-index: 10;
}

.brand { font-weight: 800; font-size: 1.25rem; text-decoration: none; color: var(--ink); }
.brand::first-letter { color: var(--accent); }

nav a, .topic { text-decoration: none; }
nav a { color: var(--ink); margin-left: 1rem; font-size: 0.95rem; }
nav a:hover { color: var(--accent); }

main { max-width: 900px; margin: 0 auto; padding: 2rem 1.4rem 4rem; }

.hero h1 { font-size: 2.2rem; line-height: 1.2; margin: 0.2rem 0 0.5rem; }

.searchbox { display: flex; gap: 0.5rem; margin: 1.2rem 0 0.8rem; }
.searchbox input {
  flex: 1;
  padding: 0.8rem 1rem;
  font-size: 1rem;
  border: 1px solid var(--line);
  border-radius: 10px;
}
.searchbox input:focus { outline: 2px solid var(--accent); border-color: transparent; }
.searchbox button {
  padding: 0.8rem 1.4rem;
  border: 0;
  border-radius: 10px;
  background: var(--accent);
  color: var(--accent-ink);
  font-weight: 700;
  cursor: pointer;
}
.searchbox.compact { max-width: 640px; }

.quick { display: flex; flex-wrap: wrap; gap: 0.9rem; align-items: center; font-size: 0.92rem; color: var(--muted); }
.check { display: inline-flex; gap: 0.35rem; align-items: center; }
select { padding: 0.3rem 0.5rem; border-radius: 8px; border: 1px solid var(--line); }

h2 { margin-top: 2.2rem; }
.muted { color: var(--muted); }

.topics { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 0.8rem; }
.topic {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 0.9rem 1rem;
  color: var(--ink);
  display: block;
}
.topic:hover { border-color: var(--accent); }
.topic small { display: block; color: var(--muted); margin-top: 0.2rem; }

.stats { font-size: 1.05rem; }

.result {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 1rem 1.1rem;
  margin: 1rem 0;
}
.result h3 { margin: 0.2rem 0; font-size: 1.08rem; }
.result h3 a { color: var(--ink); text-decoration: none; }
.result h3 a:hover { color: var(--accent); text-decoration: underline; }
.result .meta { margin: 0.3rem 0; color: var(--muted); font-size: 0.9rem; }

.chip {
  display: inline-block;
  padding: 0.12rem 0.55rem;
  border-radius: 999px;
  background: var(--chip);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.02em;
  margin-right: 0.3rem;
}
.chip.oa { background: #d9f2e9; color: var(--accent); }

.actions { margin: 0.6rem 0 0; display: flex; flex-wrap: wrap; gap: 0.5rem; align-items: center; }

.btn {
  display: inline-block;
  padding: 0.45rem 0.85rem;
  border-radius: 9px;
  background: var(--accent);
  color: var(--accent-ink);
  text-decoration: none;
  border: 0;
  font-size: 0.9rem;
  cursor: pointer;
}
.btn.ghost { background: transparent; color: var(--ink); border: 1px solid var(--line); }
.btn.small { padding: 0.3rem 0.7rem; font-size: 0.82rem; }

.cite { font-size: 0.85rem; word-break: break-word; }

#pager { margin: 1.5rem 0; display: flex; gap: 1rem; }
#pager a { color: var(--accent); text-decoration: none; font-weight: 600; }

.drawer {
  position: fixed;
  inset: 0 0 0 auto;
  width: min(680px, 94vw);
  background: var(--bg);
  border-left: 1px solid var(--line);
  box-shadow: -10px 0 30px rgba(0, 0, 0, 0.08);
  padding: 1.2rem 1.6rem;
  overflow-y: auto;
  z-index: 40;
}
.drawer-head { text-align: right; }
.drawer .ghost { font-size: 1.4rem; line-height: 1; padding: 0.3rem 0.7rem; }

footer {
  border-top: 1px solid var(--line);
  padding: 1.4rem;
  text-align: center;
  color: var(--muted);
  font-size: 0.9rem;
}