:root {
  --brand: #4f46e5;
  --brand-2: #7c3aed;
  --brand-soft: #eef2ff;
  --ink: #1f2937;
  --ink-2: #4b5563;
  --muted: #9ca3af;
  --line: #e5e7eb;
  --bg: #f8fafc;
  --card: #ffffff;
  --ok: #16a34a;
  --warn: #d97706;
  --danger: #dc2626;
  --radius: 14px;
  --shadow: 0 1px 3px rgba(0,0,0,.08), 0 8px 24px rgba(15,23,42,.06);
  --maxw: 1120px;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; }

.container { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,.85);
  backdrop-filter: saturate(180%) blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav {
  display: flex; align-items: center; gap: 8px;
  height: 64px;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 19px; margin-right: auto; }
.brand .logo {
  width: 34px; height: 34px; border-radius: 9px;
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  color: #fff; display: grid; place-items: center; font-size: 16px;
}
.brand b { background: linear-gradient(135deg, var(--brand), var(--brand-2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.nav-links { display: flex; gap: 4px; }
.nav-links a {
  padding: 8px 14px; border-radius: 9px; color: var(--ink-2); font-weight: 600; font-size: 15px;
  transition: background .15s, color .15s;
}
.nav-links a:hover { background: var(--brand-soft); color: var(--brand); }
.nav-links a.active { color: var(--brand); background: var(--brand-soft); }
.nav-auth { display: flex; align-items: center; gap: 8px; margin-left: 8px; }
.user-chip { display: flex; align-items: center; gap: 8px; font-weight: 600; color: var(--ink-2); }
.avatar {
  width: 30px; height: 30px; border-radius: 50%;
  background: linear-gradient(135deg, var(--brand), var(--brand-2)); color: #fff;
  display: grid; place-items: center; font-size: 13px; font-weight: 700;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  padding: 10px 18px; border-radius: 10px; border: 1px solid transparent;
  font-weight: 700; font-size: 15px; cursor: pointer; transition: transform .08s, box-shadow .15s, background .15s;
  font-family: inherit;
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: linear-gradient(135deg, var(--brand), var(--brand-2)); color: #fff; box-shadow: 0 6px 16px rgba(79,70,229,.3); }
.btn-primary:hover { box-shadow: 0 8px 22px rgba(79,70,229,.42); }
.btn-ghost { background: #fff; color: var(--brand); border-color: var(--line); }
.btn-ghost:hover { border-color: var(--brand); background: var(--brand-soft); }
.btn-outline { background: transparent; color: var(--ink); border-color: var(--line); }
.btn-outline:hover { border-color: var(--brand); color: var(--brand); }
.btn-sm { padding: 7px 13px; font-size: 14px; }
.btn-block { width: 100%; }

/* ---------- Hero ---------- */
.hero {
  padding: 72px 0 56px;
  background:
    radial-gradient(900px 380px at 80% -10%, rgba(124,58,237,.12), transparent),
    radial-gradient(700px 320px at 10% 10%, rgba(79,70,229,.10), transparent);
}
.hero h1 { font-size: 44px; line-height: 1.15; margin: 0 0 18px; letter-spacing: -.5px; }
.hero h1 .grad { background: linear-gradient(135deg, var(--brand), var(--brand-2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero p { font-size: 18px; color: var(--ink-2); max-width: 640px; margin: 0 0 28px; }
.hero-cta { display: flex; gap: 12px; flex-wrap: wrap; }
.hero-stats { display: flex; gap: 36px; margin-top: 40px; flex-wrap: wrap; }
.stat .n { font-size: 28px; font-weight: 800; color: var(--brand); }
.stat .l { color: var(--ink-2); font-size: 14px; }

/* ---------- Sections ---------- */
.section { padding: 56px 0; }
.section-head { text-align: center; margin-bottom: 36px; }
.section-head h2 { font-size: 30px; margin: 0 0 10px; letter-spacing: -.3px; }
.section-head p { color: var(--ink-2); margin: 0; font-size: 16px; }
.section.alt { background: #fff; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }

/* ---------- Feature grid ---------- */
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.feature-card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 28px; box-shadow: var(--shadow); transition: transform .15s, box-shadow .15s;
}
.feature-card:hover { transform: translateY(-4px); box-shadow: 0 12px 32px rgba(15,23,42,.1); }
.feature-card .ic {
  width: 48px; height: 48px; border-radius: 12px; display: grid; place-items: center;
  font-size: 24px; margin-bottom: 16px; background: var(--brand-soft); color: var(--brand);
}
.feature-card h3 { margin: 0 0 8px; font-size: 19px; }
.feature-card p { margin: 0; color: var(--ink-2); font-size: 15px; }

/* ---------- Cards (tools / products) ---------- */
.grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 22px; box-shadow: var(--shadow); display: flex; flex-direction: column; gap: 12px;
  transition: transform .15s, box-shadow .15s;
}
.card:hover { transform: translateY(-3px); box-shadow: 0 12px 30px rgba(15,23,42,.1); }
.card .thumb {
  width: 100%; height: 120px; border-radius: 10px; display: grid; place-items: center;
  font-size: 40px; background: linear-gradient(135deg, #eef2ff, #f5f3ff);
}
.card h3 { margin: 0; font-size: 18px; }
.card .desc { color: var(--ink-2); font-size: 14px; margin: 0; flex: 1; }
.card .meta { display: flex; align-items: center; gap: 8px; font-size: 13px; color: var(--muted); }
.tag { padding: 2px 9px; border-radius: 999px; font-size: 12px; font-weight: 700; }
.tag.free { background: #dcfce7; color: var(--ok); }
.tag.paid { background: #fef3c7; color: var(--warn); }
.card-actions { display: flex; gap: 8px; }

/* ---------- Forms ---------- */
.form-wrap { max-width: 420px; margin: 40px auto; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 30px; box-shadow: var(--shadow); }
.form-wrap h2 { margin: 0 0 6px; font-size: 24px; }
.form-wrap .sub { color: var(--ink-2); margin: 0 0 22px; font-size: 14px; }
.field { margin-bottom: 16px; }
.field label { display: block; font-weight: 600; margin-bottom: 6px; font-size: 14px; }
.field input, .field textarea, .field select {
  width: 100%; padding: 11px 13px; border: 1px solid var(--line); border-radius: 10px;
  font-size: 15px; font-family: inherit; color: var(--ink); background: #fff; transition: border .15s, box-shadow .15s;
}
.field input:focus, .field textarea:focus, .field select:focus { outline: none; border-color: var(--brand); box-shadow: 0 0 0 3px rgba(79,70,229,.15); }
.field textarea { min-height: 110px; resize: vertical; }
.form-note { font-size: 13px; color: var(--ink-2); margin-top: 14px; text-align: center; }
.form-note a { color: var(--brand); font-weight: 600; }
.alert { padding: 11px 14px; border-radius: 10px; font-size: 14px; margin-bottom: 16px; }
.alert.err { background: #fef2f2; color: var(--danger); border: 1px solid #fecaca; }
.alert.ok { background: #f0fdf4; color: var(--ok); border: 1px solid #bbf7d0; }

/* ---------- Tool detail ---------- */
.detail-wrap { max-width: 760px; margin: 36px auto; }
.detail-hero { display: flex; gap: 18px; align-items: center; margin-bottom: 20px; }
.detail-hero .thumb { width: 84px; height: 84px; border-radius: 16px; display: grid; place-items: center; font-size: 40px; background: linear-gradient(135deg,#eef2ff,#f5f3ff); flex: none; }
.io-box { background: #0f172a; color: #e2e8f0; border-radius: 12px; padding: 16px; font-size: 14px; white-space: pre-wrap; min-height: 80px; font-family: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace; }
.io-label { font-size: 13px; font-weight: 700; color: var(--ink-2); margin: 18px 0 8px; }

/* ---------- Office list ---------- */
.post { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 20px; box-shadow: var(--shadow); margin-bottom: 14px; }
.post h3 { margin: 0 0 6px; font-size: 17px; }
.post .when { color: var(--muted); font-size: 13px; margin-bottom: 8px; }
.post .body { color: var(--ink-2); font-size: 14px; white-space: pre-wrap; }
.badge { display: inline-block; padding: 2px 9px; border-radius: 999px; font-size: 12px; font-weight: 700; background: var(--brand-soft); color: var(--brand); margin-left: 8px; }

/* ---------- WeChat banner ---------- */
.wx-banner {
  margin: 0 auto; max-width: var(--maxw);
  background: linear-gradient(135deg, var(--brand), var(--brand-2)); color: #fff;
  border-radius: 18px; padding: 34px; display: flex; align-items: center; gap: 24px; flex-wrap: wrap;
  box-shadow: 0 12px 30px rgba(79,70,229,.3);
}
.wx-banner h3 { margin: 0 0 6px; font-size: 22px; }
.wx-banner p { margin: 0; opacity: .92; }
.wx-banner .qr { width: 96px; height: 96px; border-radius: 12px; background: #fff; padding: 6px; flex: none; }

/* ---------- Modal ---------- */
.modal-mask { position: fixed; inset: 0; background: rgba(15,23,42,.5); display: none; place-items: center; z-index: 100; padding: 20px; }
.modal-mask.show { display: grid; }
.modal { background: #fff; border-radius: 16px; padding: 26px; max-width: 360px; width: 100%; text-align: center; box-shadow: 0 20px 60px rgba(0,0,0,.3); }
.modal .qr { width: 180px; height: 180px; margin: 0 auto 14px; border-radius: 12px; }
.modal h3 { margin: 0 0 6px; }
.modal p { color: var(--ink-2); margin: 0 0 14px; font-size: 14px; }
.modal .wxid { font-weight: 800; color: var(--brand); font-size: 18px; letter-spacing: 1px; }
.modal .close { position: absolute; }

/* ---------- Footer ---------- */
.site-footer { background: #0f172a; color: #cbd5e1; margin-top: 60px; padding: 40px 0; }
.site-footer a { color: #cbd5e1; }
.site-footer .cols { display: flex; gap: 40px; flex-wrap: wrap; }
.site-footer h4 { color: #fff; font-size: 15px; margin: 0 0 12px; }
.site-footer .col a { display: block; padding: 4px 0; font-size: 14px; }
.site-footer .col a:hover { color: #fff; }
.site-footer .copy { margin-top: 28px; padding-top: 18px; border-top: 1px solid #1e293b; font-size: 13px; color: #94a3b8; }

/* ---------- Misc ---------- */
.empty { text-align: center; color: var(--muted); padding: 40px; }
.loading { text-align: center; color: var(--muted); padding: 40px; }
.mt-20 { margin-top: 20px; }
.center { text-align: center; }
.row { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; }

@media (max-width: 880px) {
  .feature-grid, .grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 32px; }
  .nav-links { display: none; }
}