:root {
  --bg: #f4f7fb;
  --card: #ffffff;
  --text: #1a2233;
  --text-2: #5b6577;
  --text-3: #8a93a6;
  --line: #e6eaf2;
  --brand: #1e80ff;
  --brand-dark: #1c6dd0;
  --brand-soft: #eaf3ff;
  --radius: 16px;
  --shadow: 0 2px 12px rgba(23, 43, 77, 0.06);
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.65;
}

.container { width: 100%; max-width: 900px; margin: 0 auto; padding: 0 20px; }
a { color: var(--brand); text-decoration: none; }
a:hover { color: var(--brand-dark); }

/* ===== 顶部导航 ===== */
.site-header {
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 90;
}
.header-inner {
  display: flex;
  align-items: center;
  gap: 18px;
  min-height: 58px;
  position: relative;
}
.logo { font-size: 18px; font-weight: 700; color: var(--text); white-space: nowrap; }
.logo:hover { color: var(--brand); }
.nav ul { display: flex; list-style: none; margin: 0; padding: 0; gap: 4px; }
.nav-item { position: relative; }
.nav-item > a {
  display: block;
  padding: 8px 14px;
  border-radius: 9px;
  color: var(--text-2);
  font-size: 15px;
  white-space: nowrap;
}
.nav-item > a:hover, .nav-item.on > a { color: var(--brand); background: var(--brand-soft); }
.sub-menu {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  min-width: 220px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  box-shadow: var(--shadow);
  padding: 6px;
  list-style: none;
  margin: 0;
  z-index: 95;
}
.nav-item:hover .sub-menu, .user-box:hover .sub-menu { display: block; }
.sub-menu a {
  display: block;
  padding: 8px 12px;
  border-radius: 8px;
  color: var(--text-2);
  font-size: 14px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.sub-menu a:hover { background: var(--brand-soft); color: var(--brand); }

.user-box { margin-left: auto; position: relative; }
.user-entry { display: flex; align-items: center; gap: 8px; padding: 6px 10px; border-radius: 10px; color: var(--text); cursor: pointer; }
.user-entry:hover { background: var(--brand-soft); }
.avatar {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px; height: 32px;
  border-radius: 50%;
  background: linear-gradient(135deg, #1e80ff, #6a5cff);
  color: #fff;
  font-size: 14px;
  font-weight: 700;
  flex: none;
}
.avatar.big { width: 56px; height: 56px; font-size: 24px; }
.user-name { font-size: 14px; font-weight: 600; max-width: 120px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.user-box .sub-menu { left: auto; right: 0; }

.auth-btns { margin-left: auto; display: flex; gap: 8px; }
.btn-ghost, .btn-main {
  display: inline-block;
  padding: 7px 16px;
  border-radius: 9px;
  font-size: 14px;
  font-weight: 600;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--text-2);
  cursor: pointer;
}
.btn-ghost:hover { border-color: var(--brand); color: var(--brand); background: var(--brand-soft); }
.btn-main { background: var(--brand); border-color: var(--brand); color: #fff; }
.btn-main:hover { background: var(--brand-dark); color: #fff; }
.btn-main.done { background: #b6c6dd; border-color: #b6c6dd; }
.btn-block { display: block; width: 100%; text-align: center; margin-top: 8px; }
.btn-main[disabled] { cursor: default; }

.lv-badge {
  display: inline-block;
  font-size: 11px;
  padding: 1px 7px;
  border-radius: 20px;
  background: #f1f3f7;
  color: #6b7280;
  font-weight: 600;
  vertical-align: 1px;
}
.lv-badge.lv0 { background: #f3f4f6; color: #9ca3af; }
.lv-badge.lv1 { background: #e8f7f0; color: #0f7a4a; }
.lv-badge.lv2 { background: #eaf3ff; color: #1e80ff; }
.lv-badge.lv3 { background: #f3e8ff; color: #7c3aed; }
.lv-badge.lv4 { background: #fff1e6; color: #d97706; }
.lv-badge.lv5 { background: #fde8e8; color: #dc2626; }

.nav-toggle { display: none; background: 0; border: 0; padding: 8px; cursor: pointer; }
.nav-toggle span { display: block; width: 20px; height: 2px; background: var(--text); margin: 4px 0; border-radius: 2px; }

/* ===== Hero ===== */
.hero {
  background: linear-gradient(180deg, #eaf3ff 0%, var(--bg) 100%);
  padding: 52px 0 34px;
  text-align: center;
}
.hero h1 { font-size: 30px; margin: 0 0 10px; letter-spacing: -.5px; }
.hero .sub { color: var(--text-2); font-size: 15px; margin: 0 auto; max-width: 640px; }
.trust { display: flex; justify-content: center; flex-wrap: wrap; gap: 8px 18px; margin-top: 18px; }
.trust i {
  font-style: normal;
  font-size: 13px;
  color: var(--text-2);
  background: #fff;
  border: 1px solid var(--line);
  padding: 5px 12px;
  border-radius: 20px;
}

/* ===== 卡片 ===== */
.main { padding: 26px 0 60px; }
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
  margin-bottom: 18px;
}
.card h2 { font-size: 17px; margin: 0 0 14px; }
.page-title { font-size: 21px; margin: 0 0 8px; }
.recent-note { font-size: 13.5px; color: var(--text-2); margin: 0 0 14px; }
.crumbs { font-size: 13px; color: var(--text-3); margin-bottom: 14px; }
.crumbs a { color: var(--text-3); }
.crumb-cur { color: var(--text-2); }

/* ===== 工具宫格 ===== */
.tool-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}
.tool-card {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 13px;
  background: #fff;
  color: var(--text);
  transition: all .15s;
}
.tool-card:hover { border-color: #bcd4f7; box-shadow: 0 6px 18px rgba(30, 128, 255, .10); transform: translateY(-2px); }
.tool-icon { font-size: 26px; line-height: 1; }
.tool-card b { font-size: 15px; }
.tool-sub { font-size: 12.5px; color: var(--text-3); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.tool-meta { font-size: 12px; color: var(--text-3); }

/* ===== 文章页 ===== */
.post-head { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; flex-wrap: wrap; }
.post-head h1 { font-size: 21px; margin: 0; }
.post-meta { display: flex; gap: 14px; font-size: 12.5px; color: var(--text-3); flex: none; }
.post-desc { color: var(--text-2); font-size: 14.5px; margin: 12px 0 0; }
.post-actions { display: flex; gap: 10px; margin-top: 16px; flex-wrap: wrap; }
.act-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff;
  color: var(--text-2);
  font-size: 14px;
  cursor: pointer;
}
.act-btn:hover { border-color: var(--brand); color: var(--brand); }
.act-btn.on { background: var(--brand-soft); border-color: var(--brand); color: var(--brand); }
.act-tip { font-size: 12.5px; color: var(--text-3); margin: 10px 0 0; }
.tool-tip { font-size: 12.5px; color: var(--text-3); margin: -6px 0 12px; }
.tool-frame {
  border: 1px solid var(--line);
  border-radius: 12px;
  overflow: hidden;
  background: #fff;
}
.tool-frame iframe { display: block; width: 100%; height: 72vh; min-height: 480px; border: 0; }

/* ===== 评论区 ===== */
.cmt-head { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 8px; }
.cmt-list { list-style: none; margin: 0 0 18px; padding: 0; }
.cmt-item { padding: 13px 0; border-bottom: 1px dashed var(--line); }
.cmt-item:last-child { border-bottom: 0; }
.cmt-meta { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; font-size: 13px; }
.cmt-name { font-weight: 600; }
.cmt-time { color: var(--text-3); font-size: 12px; }
.cmt-body { margin: 6px 0 0; font-size: 14.5px; color: var(--text); word-break: break-word; }
.cmt-img { max-width: 100%; border-radius: 8px; margin-top: 6px; }
.cmt-empty { color: var(--text-3); font-size: 14px; }
.cmt-alert { padding: 10px 14px; border-radius: 9px; font-size: 13.5px; margin: 0 0 14px; }
.cmt-ok { background: #ecfdf5; border: 1px solid #a7f3d0; color: #047857; }
.cmt-err { background: #fef2f2; border: 1px solid #fecaca; color: #b91c1c; }
.cmt-form { margin-top: 6px; }
.cmt-row { display: grid; grid-template-columns: 64px 1fr; gap: 10px; align-items: start; margin-bottom: 10px; }
.cmt-label { font-size: 13px; color: var(--text-2); padding-top: 9px; }
.cmt-input, .cmt-text {
  width: 100%;
  padding: 9px 11px;
  border: 1px solid #dfe5f0;
  border-radius: 9px;
  font: inherit;
  font-size: 14px;
  background: #fcfdfe;
}
.cmt-text { min-height: 80px; resize: vertical; }
.cmt-input:focus, .cmt-text:focus { outline: 0; border-color: #93b0f0; box-shadow: 0 0 0 3px rgba(30, 128, 255, .10); }
.cmt-actions { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.cmt-tip { font-size: 12px; color: var(--text-3); }

/* ===== 认证 / 用户中心 ===== */
.auth-card { max-width: 420px; margin: 30px auto; }
.auth-tabs { display: flex; gap: 6px; margin-bottom: 18px; }
.auth-tabs a { flex: 1; text-align: center; padding: 9px; border-radius: 9px; border: 1px solid var(--line); color: var(--text-2); font-size: 14px; }
.auth-tabs a.on { background: var(--brand); border-color: var(--brand); color: #fff; }
.auth-benefit { font-size: 12.5px; color: var(--text-2); background: var(--brand-soft); border-radius: 9px; padding: 9px 12px; }
.auth-alt { text-align: center; font-size: 13px; color: var(--text-2); margin: 14px 0 0; }

.user-hero-main { display: flex; align-items: center; gap: 16px; }
.user-hero-main > div { flex: 1; min-width: 0; }
.user-title { font-size: 19px; margin: 0 0 4px; }
.user-sub { color: var(--text-2); font-size: 13.5px; margin: 0; }
.sign-box { flex: none; }
.mylist { list-style: none; margin: 0; padding: 0; }
.mylist li { display: flex; justify-content: space-between; gap: 12px; padding: 9px 2px; border-bottom: 1px dashed var(--line); font-size: 14px; }
.mylist li:last-child { border-bottom: 0; }
.mylist span { color: var(--text-3); font-size: 12.5px; flex: none; }

/* ===== 表格 / 列表 ===== */
.cna-table { width: 100%; border-collapse: collapse; font-size: 14px; }
.cna-table th, .cna-table td { text-align: left; padding: 8px 8px; border-bottom: 1px solid #eef1f7; }
.cna-table th { font-size: 12.5px; color: var(--text-3); font-weight: 600; }
.pt-plus { color: #0f7a4a; font-weight: 600; }
.pt-minus { color: #dc2626; font-weight: 600; }

.code-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 8px; }
.code-grid a {
  display: block;
  padding: 9px 11px;
  border: 1px solid var(--line);
  border-radius: 9px;
  background: #fff;
  color: var(--text-2);
  font-size: 13.5px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.code-grid a:hover { border-color: #c7d6f5; background: var(--brand-soft); color: var(--brand); }
.code-grid a em { font-style: normal; font-family: ui-monospace, Menlo, Consolas, monospace; color: var(--text-3); font-size: 12px; margin-right: 6px; }

.feat { margin-bottom: 10px; }
.feat h3 { font-size: 15px; margin: 0 0 4px; }
.feat h3 em {
  font-style: normal;
  display: inline-flex;
  width: 22px; height: 22px;
  align-items: center; justify-content: center;
  border-radius: 7px;
  background: var(--brand-soft);
  color: var(--brand);
  font-size: 13px;
  margin-right: 8px;
}
.feat p { margin: 0; color: var(--text-2); font-size: 14px; }

/* ===== 友链 / 页脚 ===== */
.flink-box { display: flex; flex-wrap: wrap; gap: 6px 14px; align-items: baseline; padding-bottom: 6px; margin-bottom: 14px; border-bottom: 1px dashed var(--line); }
.flink-label { font-size: 13px; color: var(--text-3); }
.flink-box a { font-size: 13px; color: var(--text-3); }
.site-footer { border-top: 1px solid var(--line); background: #fff; padding: 26px 0 34px; font-size: 13px; color: var(--text-2); }
.site-footer p { margin: 4px 0; }
.foot-links a { color: var(--text-2); }
.foot-links .dot { margin: 0 8px; color: var(--text-3); }
.foot-icp a { color: var(--text-3); }

/* ===== 后台页签（用户中心/页面内） ===== */
.adm-tabs { display: flex; gap: 6px; flex-wrap: wrap; margin-bottom: 16px; }
.adm-tabs a { padding: 7px 14px; border-radius: 8px; border: 1px solid var(--line); background: #fff; color: var(--text-2); font-size: 13.5px; }
.adm-tabs a.on { background: var(--brand); border-color: var(--brand); color: #fff; }

.empty { text-align: center; padding: 46px 24px; }
.empty h1 { font-size: 22px; margin: 0 0 8px; }

/* ===== 移动端 ===== */
@media (max-width: 760px) {
  .tool-grid { grid-template-columns: 1fr 1fr; }
  .hero h1 { font-size: 24px; }
  .nav-toggle { display: block; margin-left: auto; }
  .user-box, .auth-btns { display: none; }
  .nav { display: none; position: absolute; top: 100%; left: 0; right: 0; background: #fff; border-bottom: 1px solid var(--line); padding: 10px 16px 14px; }
  .nav.open { display: block; }
  .nav ul { flex-direction: column; gap: 2px; }
  .nav-item.has-sub > a::after { content: ' ▾'; color: var(--text-3); font-size: 12px; }
  .nav-item .sub-menu { display: block; position: static; border: 0; box-shadow: none; padding: 0 0 0 14px; }
  .cmt-row { grid-template-columns: 1fr; }
  .cmt-label { padding-top: 0; }
  .user-hero-main { flex-wrap: wrap; }
  .sign-box { width: 100%; }
  .tool-frame iframe { height: 62vh; min-height: 400px; }
}