:root {
  --bg: #f6f7fb;
  --card: #ffffff;
  --text: #1f2329;
  --muted: #6b7280;
  --primary: #4f46e5;
  --primary-d: #4338ca;
  --border: #e5e7eb;
  --radius: 14px;
  --shadow: 0 1px 3px rgba(0,0,0,.06), 0 8px 24px rgba(0,0,0,.04);
  --maxw: 1040px;
}
* { 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", "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }
.container { max-width: var(--maxw); margin: 0 auto; padding: 0 18px; }

/* Header */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,.92);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--border);
}
.header-inner { display: flex; align-items: center; gap: 18px; height: 60px; }
.logo { font-weight: 800; font-size: 20px; color: var(--text); letter-spacing: -.5px; }
.logo:hover { text-decoration: none; }
.logo span { color: var(--primary); }
.nav { margin-left: auto; display: flex; gap: 18px; }
.nav a { color: var(--muted); font-weight: 600; font-size: 15px; }
.nav a:hover { color: var(--primary); text-decoration: none; }
.menu-toggle {
  display: none; margin-left: auto; background: none; border: 0;
  font-size: 24px; cursor: pointer; color: var(--text);
}

/* Hero */
.hero { padding: 54px 0 30px; text-align: center; }
.hero h1 { font-size: 38px; margin: 0 0 12px; letter-spacing: -1px; }
.hero .lead { font-size: 17px; color: var(--muted); max-width: 620px; margin: 0 auto 22px; }
#tool-search {
  width: 100%; max-width: 520px; padding: 14px 18px; font-size: 16px;
  border: 1px solid var(--border); border-radius: 999px; outline: none;
  box-shadow: var(--shadow); background: #fff;
}
#tool-search:focus { border-color: var(--primary); }

/* Tool grid (home) */
.section-title { font-size: 22px; margin: 36px 0 14px; }
.tool-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr));
  gap: 16px; padding-bottom: 40px;
}
.tool-card-link { display: block; }
.tool-card-link:hover { text-decoration: none; }
.tool-card-link .tool-card { height: 100%; }
.tool-card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 18px; box-shadow: var(--shadow); transition: transform .12s ease, box-shadow .12s ease;
}
.tool-card-link:hover .tool-card { transform: translateY(-3px); box-shadow: 0 6px 30px rgba(0,0,0,.10); }
.tool-card h3 { margin: 0 0 6px; font-size: 17px; color: var(--text); }
.tool-card p { margin: 0; color: var(--muted); font-size: 14px; }
.tool-card .ico { font-size: 26px; display: block; margin-bottom: 8px; }

/* Breadcrumb & page */
.breadcrumb { color: var(--muted); font-size: 14px; margin: 22px 0 6px; }
.breadcrumb a { color: var(--muted); }
.page-title { font-size: 30px; margin: 4px 0 8px; letter-spacing: -.5px; }
.lead { color: var(--muted); margin: 0 0 18px; }

/* Ad slot */
.ad-slot {
  margin: 18px 0; min-height: 90px; border: 1px dashed #cbd5e1;
  border-radius: 10px; display: flex; align-items: center; justify-content: center;
  background: #fbfcfe; color: #94a3b8; font-size: 13px; letter-spacing: .5px;
}
.ad-label { text-transform: uppercase; }

/* Tool inner */
.tool-card.inner { background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 22px; box-shadow: var(--shadow); }
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.grid-3 { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 18px; }
.mini { border: 1px solid var(--border); border-radius: 10px; padding: 14px; background: #fafbff; }
.mini h3 { margin: 0 0 10px; font-size: 15px; }
.row { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; margin-bottom: 10px; }
.op { color: var(--muted); font-weight: 700; }

label { display: block; font-size: 14px; font-weight: 600; margin: 10px 0 6px; color: #374151; }
input, select, textarea {
  width: 100%; padding: 11px 12px; font-size: 15px; border: 1px solid var(--border);
  border-radius: 10px; outline: none; background: #fff; color: var(--text);
  font-family: inherit;
}
input:focus, select:focus, textarea:focus { border-color: var(--primary); }
textarea { resize: vertical; min-height: 120px; }
.result { margin-top: 10px; font-weight: 700; font-size: 17px; color: var(--primary-d);
  word-break: break-all; }
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  background: var(--primary); color: #fff; border: 0; border-radius: 10px;
  padding: 11px 18px; font-size: 15px; font-weight: 600; cursor: pointer;
  transition: background .12s ease; width: auto;
}
.btn:hover { background: var(--primary-d); }
.btn.ghost { background: #fff; color: var(--primary); border: 1px solid var(--border); }
.btn.block { width: 100%; }
.copy-btn { margin-top: 8px; }

/* misc */
.swatches { display: flex; gap: 10px; align-items: center; margin: 10px 0; }
.swatch { width: 56px; height: 56px; border-radius: 10px; border: 1px solid var(--border); }
.strength { height: 8px; border-radius: 6px; background: #e5e7eb; overflow: hidden; margin-top: 8px; }
.strength > i { display: block; height: 100%; width: 0; transition: width .2s, background .2s; }
.preview { border: 1px solid var(--border); border-radius: 10px; padding: 14px; min-height: 120px;
  background: #fff; overflow: auto; }
.split { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.countdown { font-size: 34px; font-weight: 800; text-align: center; color: var(--primary-d);
  letter-spacing: 1px; margin: 14px 0; }
#qr-box { display: flex; justify-content: center; padding: 10px; background: #fff;
  border: 1px solid var(--border); border-radius: 10px; margin-top: 10px; }

/* related */
.related { margin: 30px 0; }
.related h2 { font-size: 20px; margin-bottom: 12px; }
.related-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 12px; }
.related-grid a { border: 1px solid var(--border); border-radius: 10px; padding: 12px 14px;
  background: #fff; color: var(--text); font-weight: 600; box-shadow: var(--shadow); }
.related-grid a:hover { border-color: var(--primary); text-decoration: none; }

/* Footer */
.site-footer { border-top: 1px solid var(--border); margin-top: 30px; padding: 26px 0;
  background: #fff; }
.site-footer p { margin: 4px 0; font-size: 14px; }
.site-footer .muted { color: var(--muted); }
.site-footer .beian { display: flex; align-items: center; justify-content: center; gap: 6px; margin-top: 8px; }
.site-footer .beian img { width: 20px; height: 20px; display: block; }
.site-footer .beian a { color: var(--primary); text-decoration: none; }
.site-footer .beian a:hover { text-decoration: underline; }

/* Responsive */
@media (max-width: 720px) {
  .hero h1 { font-size: 28px; }
  .grid-2, .grid-3, .split { grid-template-columns: 1fr; }
  .menu-toggle { display: block; }
  .nav { display: none; position: absolute; top: 60px; left: 0; right: 0;
    background: #fff; flex-direction: column; padding: 12px 18px; border-bottom: 1px solid var(--border); }
  .nav.open { display: flex; }
}

/* Blog */
.blog-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 18px; padding-bottom: 40px; }
.blog-card { display: block; }
.blog-card:hover { text-decoration: none; }
.blog-card .blog-card-inner { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px; box-shadow: var(--shadow); height: 100%; transition: transform .12s ease, box-shadow .12s ease; }
.blog-card:hover .blog-card-inner { transform: translateY(-3px); box-shadow: 0 6px 30px rgba(0,0,0,.1); }
.blog-cat { display: inline-block; font-size: 12px; font-weight: 700; color: var(--primary); background: #eef2ff;
  padding: 3px 10px; border-radius: 999px; margin-bottom: 10px; }
.blog-card h3 { margin: 0 0 8px; font-size: 18px; color: var(--text); }
.blog-card p { margin: 0; color: var(--muted); font-size: 14px; }
.blog-date { display: block; margin-top: 12px; font-size: 13px; color: #9ca3af; }
.blog-meta { color: var(--muted); font-size: 14px; margin: 0 0 18px; }
.post { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 26px; box-shadow: var(--shadow); line-height: 1.8; }
.post h2 { margin-top: 28px; font-size: 22px; }
.post h3 { margin-top: 20px; font-size: 18px; }
.post p { margin: 12px 0; }
.post ul, .post ol { margin: 12px 0; padding-left: 22px; }
.post li { margin: 6px 0; }
.post a { color: var(--primary); text-decoration: underline; }
.post code { background: #f1f5f9; padding: 2px 6px; border-radius: 6px; font-size: 14px; }