:root {
  --bg: #f5f7fb;
  --card: #ffffff;
  --ink: #0f172a;
  --muted: #64748b;
  --line: #e5e9f2;
  --brand: #2563eb;
  --brand-2: #7c3aed;
  --ok: #16a34a;
  --danger: #dc2626;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(15, 23, 42, .08);
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background:
    radial-gradient(900px 500px at 85% -10%, rgba(124, 58, 237, .10), transparent 60%),
    radial-gradient(700px 420px at -10% 10%, rgba(37, 99, 235, .10), transparent 60%),
    var(--bg);
  color: var(--ink);
  line-height: 1.6;
}
a { color: var(--brand); text-decoration: none; }
a:hover { opacity: .85; }
.wrap { width: min(1120px, calc(100% - 32px)); margin: 0 auto; }

.topbar {
  position: sticky; top: 0; z-index: 20;
  backdrop-filter: blur(12px);
  background: rgba(255, 255, 255, .75);
  border-bottom: 1px solid var(--line);
}
.topbar .wrap { display: flex; align-items: center; justify-content: space-between; height: 60px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; color: var(--ink); }
.logo {
  width: 30px; height: 30px; border-radius: 9px; color: #fff; display: grid; place-items: center;
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  font-size: 15px;
}
.topbar nav { display: flex; gap: 18px; font-size: 14px; }
.topbar nav a { color: var(--muted); }
.topbar nav a:hover { color: var(--brand); }

.hero { padding: 54px 0 26px; text-align: center; }
.hero h1 { margin: 0 0 8px; font-size: clamp(26px, 4vw, 38px); letter-spacing: -.02em; }
.hero p { margin: 0 auto 22px; color: var(--muted); max-width: 620px; }
.badge {
  display: inline-flex; align-items: center; gap: 6px; padding: 5px 12px; border-radius: 999px;
  background: rgba(37, 99, 235, .10); color: var(--brand); font-size: 13px; font-weight: 600;
  margin-bottom: 14px;
}
.badge::before { content: ""; width: 7px; height: 7px; border-radius: 50%; background: var(--ok); }

.searchbox {
  display: flex; gap: 10px; background: var(--card); border: 1px solid var(--line);
  padding: 8px; border-radius: 16px; box-shadow: var(--shadow); max-width: 760px; margin: 0 auto;
  transition: transform .18s ease, box-shadow .18s ease;
}
.searchbox:focus-within { transform: translateY(-1px); box-shadow: 0 16px 40px rgba(37, 99, 235, .14); }
.searchbox input {
  flex: 1; border: 0; outline: 0; padding: 12px 14px; font-size: 16px; background: transparent; color: var(--ink);
}
.btn {
  border: 0; border-radius: 11px; padding: 10px 18px; font-size: 14px; font-weight: 600;
  background: linear-gradient(135deg, var(--brand), var(--brand-2)); color: #fff; cursor: pointer;
  transition: transform .16s ease, opacity .16s ease;
}
.btn:hover { transform: translateY(-1px); opacity: .92; }
.btn:active { transform: translateY(0); }
.btn.ghost { background: transparent; color: var(--muted); border: 1px solid var(--line); }
.btn.danger { background: var(--danger); }
.btn.sm { padding: 6px 12px; font-size: 13px; border-radius: 9px; }

.meta-row { display: flex; gap: 18px; justify-content: center; margin-top: 16px; color: var(--muted); font-size: 13px; }

.results { padding: 10px 0 60px; }
.result {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 18px 20px; margin-bottom: 14px; box-shadow: 0 4px 14px rgba(15, 23, 42, .04);
  animation: fadeUp .28s ease both;
}
.result:hover { border-color: #c7d2fe; }
.result .q { font-weight: 700; font-size: 16px; margin: 0 0 8px; }
.result .a { white-space: pre-wrap; color: #1e293b; }
.result .tags { margin-top: 12px; display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.tag {
  font-size: 12px; padding: 2px 9px; border-radius: 999px; background: #eef2ff; color: #4338ca;
}
.tag.gray { background: #f1f5f9; color: var(--muted); }
.copy { margin-left: auto; font-size: 12px; color: var(--brand); background: none; border: 0; cursor: pointer; }
.empty {
  text-align: center; color: var(--muted); padding: 54px 16px; background: var(--card);
  border: 1px dashed var(--line); border-radius: var(--radius);
}
.empty .big { font-size: 34px; margin-bottom: 8px; }

.foot { border-top: 1px solid var(--line); color: var(--muted); font-size: 13px; padding: 22px 0; text-align: center; }

/* 管理后台 */
.admin-head { display: flex; align-items: center; justify-content: space-between; gap: 14px; padding: 26px 0 16px; flex-wrap: wrap; }
.admin-head h1 { margin: 0; font-size: 22px; }
.toolbar { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; padding: 14px 0; }
.toolbar input[type=text] {
  flex: 1; min-width: 220px; padding: 10px 14px; border: 1px solid var(--line); border-radius: 10px; outline: none;
}
.panel { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
table { width: 100%; border-collapse: collapse; }
th, td { text-align: left; padding: 12px 14px; border-bottom: 1px solid var(--line); font-size: 14px; vertical-align: top; }
th { background: #f8fafc; color: var(--muted); font-weight: 600; white-space: nowrap; }
tr:hover td { background: #fafbff; }
.cell-q { font-weight: 600; max-width: 320px; }
.cell-a { color: #475569; max-width: 420px; white-space: pre-wrap; }
.ops { display: flex; gap: 8px; white-space: nowrap; }
.pager { display: flex; gap: 8px; justify-content: flex-end; padding: 14px; }
.pager a, .pager span { padding: 6px 11px; border: 1px solid var(--line); border-radius: 8px; font-size: 13px; color: var(--muted); }
.pager .on { background: var(--brand); border-color: var(--brand); color: #fff; }
.stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin-bottom: 16px; }
.stat { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 14px 16px; }
.stat b { display: block; font-size: 22px; }
.stat span { color: var(--muted); font-size: 13px; }

.modal-mask {
  position: fixed; inset: 0; background: rgba(15, 23, 42, .45); backdrop-filter: blur(3px);
  display: none; align-items: center; justify-content: center; z-index: 50; padding: 18px;
}
.modal-mask.show { display: flex; animation: fadeIn .16s ease; }
.modal {
  width: min(720px, 100%); max-height: 90vh; overflow: auto; background: var(--card);
  border-radius: 16px; padding: 22px; box-shadow: 0 30px 80px rgba(0, 0, 0, .28);
  animation: popIn .2s cubic-bezier(.2, .9, .3, 1.2);
}
.modal h3 { margin: 0 0 14px; }
.field { margin-bottom: 12px; }
.field label { display: block; font-size: 13px; color: var(--muted); margin-bottom: 6px; }
.field input, .field textarea, .field select {
  width: 100%; padding: 10px 12px; border: 1px solid var(--line); border-radius: 10px;
  font-size: 14px; font-family: inherit; outline: none; background: #fff;
}
.field textarea { min-height: 110px; resize: vertical; }
.modal-foot { display: flex; justify-content: flex-end; gap: 10px; margin-top: 16px; }
.toast {
  position: fixed; left: 50%; bottom: 28px; transform: translateX(-50%) translateY(16px);
  background: #0f172a; color: #fff; padding: 10px 18px; border-radius: 10px; font-size: 14px;
  opacity: 0; pointer-events: none; transition: all .24s ease; z-index: 80;
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

@keyframes fadeUp { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: none; } }
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
@keyframes popIn { from { opacity: 0; transform: scale(.96) translateY(8px); } to { opacity: 1; transform: none; } }

@media (max-width: 760px) {
  .topbar nav { gap: 10px; font-size: 13px; }
  .hero { padding: 34px 0 18px; }
  .stats { grid-template-columns: 1fr; }
  .cell-a { display: none; }
  th:nth-child(3), td:nth-child(3) { display: none; }
}