:root {
  --bg: #f5f7fb;
  --surface: #ffffff;
  --ink: #15223b;
  --muted: #64748b;
  --line: #e2e8f3;
  --primary: #2457e6;
  --primary-ink: #ffffff;
  --accent: #0f9d76;
  --warn: #b45309;
  --danger: #d92d20;
  --shadow: 0 18px 50px rgba(22, 40, 84, 0.10);
  --radius: 16px;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: radial-gradient(1100px 600px at 10% -10%, #e6ecff 0%, transparent 60%), var(--bg);
  color: var(--ink);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }
.wrap { max-width: 1080px; margin: 0 auto; padding: 28px 20px 64px; }
.topbar {
  display: flex; align-items: center; justify-content: space-between;
  gap: 16px; margin-bottom: 26px;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; letter-spacing: .2px; }
.logo {
  width: 34px; height: 34px; border-radius: 10px;
  background: linear-gradient(135deg, #2457e6, #6f9bff);
  display: grid; place-items: center; color: #fff; font-size: 18px; font-weight: 800;
}
.muted { color: var(--muted); }
.card {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--shadow); padding: 26px;
}
.grid { display: grid; gap: 18px; }
.grid.two { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid.three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
@media (max-width: 820px) { .grid.two, .grid.three { grid-template-columns: 1fr; } }
h1 { font-size: 24px; margin: 0 0 6px; letter-spacing: -.3px; }
h2 { font-size: 18px; margin: 0 0 14px; }
h3 { font-size: 15px; margin: 0 0 10px; }
p.lead { color: var(--muted); margin: 0 0 20px; line-height: 1.6; }
label { display: block; font-size: 13px; font-weight: 600; margin: 0 0 6px; color: #33415c; }
.input, select, textarea {
  width: 100%; padding: 11px 13px; border-radius: 11px; border: 1px solid var(--line);
  background: #fbfcff; font-size: 14px; color: var(--ink); outline: none;
  transition: border-color .15s, box-shadow .15s;
}
.input:focus, select:focus { border-color: #9db6ff; box-shadow: 0 0 0 3px rgba(36, 87, 230, .12); }
.field { margin-bottom: 14px; }
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  border: 1px solid transparent; border-radius: 11px; padding: 11px 16px;
  background: var(--primary); color: var(--primary-ink); font-size: 14px; font-weight: 600;
  cursor: pointer; transition: transform .08s, opacity .15s, background .15s;
}
.btn:hover { opacity: .94; }
.btn:active { transform: translateY(1px); }
.btn.ghost { background: transparent; color: var(--primary); border-color: #c9d6ff; }
.btn.subtle { background: #eef2f9; color: #33415c; border-color: var(--line); }
.btn.danger { background: #fff1f0; color: var(--danger); border-color: #ffd3cf; }
.btn:disabled { opacity: .55; cursor: not-allowed; }
.row { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; }
.tabs { display: flex; gap: 6px; background: #f0f3fa; padding: 5px; border-radius: 12px; margin-bottom: 20px; }
.tab {
  flex: 1; text-align: center; padding: 9px 12px; border-radius: 9px; border: 0;
  background: transparent; color: var(--muted); font-weight: 600; cursor: pointer; font-size: 14px;
}
.tab.active { background: #fff; color: var(--ink); box-shadow: 0 4px 14px rgba(22,40,84,.08); }
.badge {
  display: inline-flex; align-items: center; gap: 5px; padding: 3px 9px; border-radius: 999px;
  font-size: 12px; font-weight: 600; background: #eef2f9; color: #44506a;
}
.badge.ok { background: #e7f7f1; color: #0b7a5c; }
.badge.warn { background: #fff5e6; color: var(--warn); }
.badge.bad { background: #fff1f0; color: var(--danger); }
.stat { padding: 18px; border-radius: 14px; background: #fbfcff; border: 1px solid var(--line); }
.stat .label { font-size: 12px; color: var(--muted); letter-spacing: .3px; }
.stat .value { font-size: 28px; font-weight: 800; margin-top: 6px; letter-spacing: -.5px; }
.stat .hint { font-size: 12px; color: var(--muted); margin-top: 4px; }
.credit-hero {
  background: linear-gradient(135deg, #1f49c9 0%, #4f7bf0 55%, #7aa2ff 100%);
  color: #fff; border: 0;
}
.credit-hero .label, .credit-hero .hint { color: rgba(255,255,255,.78); }
.credit-hero .value { font-size: 44px; }
table { width: 100%; border-collapse: collapse; font-size: 13px; }
th, td { text-align: left; padding: 11px 10px; border-bottom: 1px solid #edf1f8; vertical-align: middle; }
th { color: var(--muted); font-weight: 600; font-size: 12px; letter-spacing: .3px; }
tbody tr:hover { background: #f9fbff; }
.table-wrap { overflow-x: auto; }
.empty { padding: 28px; text-align: center; color: var(--muted); font-size: 14px; }
.msg { margin: 12px 0 0; padding: 10px 12px; border-radius: 10px; font-size: 13px; display: none; }
.msg.error { display: block; background: #fff1f0; color: var(--danger); border: 1px solid #ffd3cf; }
.msg.ok { display: block; background: #e7f7f1; color: #0b7a5c; border: 1px solid #bfe9da; }
.msg.info { display: block; background: #eef3ff; color: #24469e; border: 1px solid #cfdaff; }
.check { display: flex; gap: 9px; align-items: flex-start; font-size: 13px; color: #44506a; margin: 10px 0; }
.check input { width: 16px; height: 16px; margin-top: 2px; }
.kv { display: grid; grid-template-columns: 130px 1fr; gap: 8px 14px; font-size: 13px; }
.kv .k { color: var(--muted); }
pre.draft {
  white-space: pre-wrap; word-break: break-word; background: #fbfcff; border: 1px solid var(--line);
  border-radius: 12px; padding: 14px; font-size: 13px; line-height: 1.6; max-height: 320px; overflow: auto;
}
.section-gap { margin-top: 22px; }
.foot { margin-top: 26px; color: var(--muted); font-size: 12px; text-align: center; }
.hidden { display: none !important; }
img.preview {
  display: block; max-width: 100%; max-height: 420px; margin: 12px 0 0;
  border: 1px solid var(--line); border-radius: 12px; background: #fff;
}
.pill-credit { color: var(--accent); font-weight: 700; }

/* 公式排版：正常路径为内核 KaTeX（本地制品，断网可用）；降级路径沿用同一套本地排版样式 */
.math { font-family: "Cambria Math", Georgia, serif; }
.mfrac { display: inline-flex; flex-direction: column; vertical-align: middle; text-align: center; margin: 0 .15em; }
.mnum { border-bottom: 1px solid currentColor; padding: 0 .18em; line-height: 1.2; }
.mden { padding: 0 .18em; line-height: 1.2; }
.msqrt { display: inline-flex; align-items: flex-start; margin: 0 .1em; }
.mroot { font-size: .62em; line-height: 1; margin-right: -.28em; margin-top: -.18em; }
.mrad { font-size: 1.2em; line-height: 1; }
.mbody { border-top: 1px solid currentColor; padding: 0 .12em; margin-top: .08em; }
.math sup, .math sub { font-size: .72em; }
.mvec { display: inline-block; position: relative; padding-top: .36em; }
.mvec::before { content: '\2192'; position: absolute; left: 50%; top: 0; transform: translateX(-50%) scaleX(.8); font-size: .62em; line-height: 1; }
.moline { border-top: 1px solid currentColor; padding-top: .04em; }
.mhat { display: inline-block; position: relative; padding-top: .3em; }
.mhat::before { content: '\02C6'; position: absolute; left: 50%; top: 0; transform: translateX(-50%); font-size: .9em; }
.muline { border-bottom: 1px solid currentColor; padding-bottom: .04em; }
.math-katex { display: inline-block; max-width: 100%; vertical-align: middle; }
.math-katex .katex { font-size: 1.02em; }
.math-fail { font-size: 11px; color: var(--muted); margin-left: 4px; user-select: none; }
.stem-preview { min-height: 44px; margin-top: 6px; padding: 8px 10px; border-radius: 10px; background: #f8f9fc; font-size: 15px; line-height: 1.9; overflow-x: auto; overflow-wrap: anywhere; }
.stem-preview .hint, .math-hint { font-size: 12px; color: var(--muted); }
.kv { line-height: 1.75; }
.kv .katex { font-size: 1.05em; }

/* 后台渠道护栏：演示渠道必须醒目，避免运营误判为真实收款/发送 */
.provider-guard { display: grid; gap: 10px; margin: 0 0 18px; }
.provider-guard .item {
  display: flex; flex-wrap: wrap; gap: 6px 14px; align-items: baseline;
  padding: 12px 14px; border-radius: 12px; border: 1px solid #f3d08a;
  background: #fffbeb; color: #7c4a03; font-size: 13px;
}
.provider-guard .item strong { font-size: 14px; }
.provider-guard .item .meta { color: #92660a; font-size: 12px; }