:root {
  --help-bg: #f6f8fb;
  --help-code-bg: #edf4ff;
  --help-code-text: #1e3a8a;
  --help-info-bg: #eff6ff;
  --help-info-border: #bfdbfe;
  --help-line: #d9e2ef;
  --help-nav-active: #eaf2ff;
  --help-primary: #135bd7;
  --help-primary-dark: #0f4fbd;
  --help-primary-border: #b9cced;
  --help-space-5: 20px;
  --help-video-max-width: 22rem;
  --help-video-max-height: min(30rem, 65vh);
  --help-media-radius: 8px;
  --help-surface: #fff;
  --help-surface-muted: #f1f5f9;
  --help-surface-subtle: #f8fafc;
  --help-text: #475569;
  --help-text-code: #e2e8f0;
  --help-text-strong: #0f172a;
  --help-text-soft: #64748b;
  background: var(--help-bg);
  color: var(--help-text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-synthesis: none;
}

* { box-sizing: border-box; }

body { margin: 0; }

a { color: var(--help-primary-dark); }

.help-shell { min-height: 100vh; }

.help-header,
.help-main,
.help-footer {
  width: min(100% - 32px, 1120px);
  margin: 0 auto;
}

.help-header {
  align-items: center;
  display: flex;
  justify-content: space-between;
  min-height: 72px;
  gap: 16px;
}

.help-brand {
  color: var(--help-text-strong);
  font-size: 18px;
  font-weight: 700;
  text-decoration: none;
}

.help-brand-mark {
  align-items: center;
  background: var(--help-primary);
  border-radius: 8px;
  color: var(--help-surface);
  display: inline-flex;
  height: 32px;
  justify-content: center;
  margin-right: 8px;
  width: 32px;
}

.help-login {
  border: 1px solid var(--help-primary-border);
  border-radius: 8px;
  color: var(--help-primary-dark);
  font-size: 14px;
  font-weight: 600;
  padding: 8px 12px;
  text-decoration: none;
}

.help-main { padding: 24px 0 40px; }

.help-layout { display: grid; gap: 20px; grid-template-columns: 240px minmax(0, 1fr); }

.help-nav,
.help-article {
  background: var(--help-surface);
  border: 1px solid var(--help-line);
  border-radius: 12px;
}

.help-nav { align-self: start; padding: 16px; }

.help-nav-title { color: var(--help-text-soft); font-size: 12px; font-weight: 600; margin: 0 0 8px; }

.help-nav-group + .help-nav-group { border-top: 1px solid var(--help-line); margin-top: 12px; padding-top: 12px; }

.help-nav-list { list-style: none; margin: 0; padding: 0; }

.help-nav-list li + li { margin-top: 2px; }

.help-nav-list a {
  border-radius: 6px;
  display: block;
  font-size: 13px;
  line-height: 1.45;
  padding: 7px 8px;
  text-decoration: none;
}

.help-nav-list a[aria-current="page"] { background: var(--help-nav-active); color: var(--help-primary-dark); font-weight: 700; }

.help-article { min-width: 0; padding: 32px; }

.help-article h1,
.help-article h2,
.help-article h3,
.help-article h4 { color: var(--help-text-strong); letter-spacing: 0; }

.help-article h1 { font-size: 30px; line-height: 1.25; margin: 0 0 16px; }

.help-article h2 { border-top: 1px solid var(--help-line); font-size: 22px; line-height: 1.3; margin: 32px 0 12px; padding-top: 24px; }

.help-article h3 { font-size: 17px; line-height: 1.4; margin: 24px 0 8px; }

.help-article p,
.help-article li { color: var(--help-text); font-size: 15px; line-height: 1.8; }

.help-article p { margin: 8px 0; }

.help-article ul,
.help-article ol { margin: 8px 0 16px; padding-left: 24px; }

.help-article a { font-weight: 600; }

.help-article code { background: var(--help-code-bg); border-radius: 6px; color: var(--help-code-text); font-size: 13px; padding: 2px 6px; word-break: break-word; }

.help-article pre { background: var(--help-text-strong); border-radius: 10px; color: var(--help-text-code); overflow-x: auto; padding: 16px; }

.help-article pre code { background: transparent; color: inherit; padding: 0; white-space: pre; }

.help-article blockquote { background: var(--help-info-bg); border: 1px solid var(--help-info-border); border-left: 4px solid var(--help-primary); border-radius: 10px; color: var(--help-code-text); margin: 16px 0; padding: 12px 16px; }

.help-article table { border-collapse: collapse; display: block; margin: 16px 0; overflow-x: auto; width: 100%; }

.help-article th,
.help-article td { border: 1px solid var(--help-line); padding: 8px 12px; text-align: left; vertical-align: top; }

.help-article th { background: var(--help-surface-muted); color: var(--help-text-strong); white-space: nowrap; }

.help-article img { background: var(--help-surface-subtle); border: 1px solid var(--help-line); border-radius: 12px; display: block; height: auto; margin: 16px 0; max-height: 620px; max-width: 100%; object-fit: contain; }

.help-operation-video { background: var(--help-surface-subtle); border: 1px solid var(--help-line); border-radius: 12px; margin: 0 0 24px; padding: 16px; }

.help-operation-flow-section { margin: 0 0 16px; }

.help-operation-eyebrow { color: var(--help-primary-dark); font-size: 12px; font-weight: 600; margin: 0 0 8px; }

.help-operation-flow { display: grid; gap: 24px; grid-template-columns: repeat(3, minmax(0, 1fr)); list-style: none; margin: 0; padding: 0; }

.help-operation-step { background: var(--help-surface); border: 1px solid var(--help-line); border-radius: 8px; display: grid; gap: 8px; grid-template-columns: auto minmax(0, 1fr); min-width: 0; padding: 12px; position: relative; }

.help-operation-step:not(:last-child)::after { color: var(--help-primary); content: '→'; font-size: 24px; font-weight: 600; position: absolute; right: calc(var(--help-space-5) * -1); top: calc(50% - 16px); z-index: 1; }

.help-operation-number { align-items: center; background: var(--help-primary); border-radius: 999px; color: var(--help-surface); display: inline-flex; font-size: 12px; font-weight: 600; height: 28px; justify-content: center; width: 28px; }

.help-operation-step strong { color: var(--help-text-strong); display: block; font-size: 14px; line-height: 1.4; }

.help-operation-step p { color: var(--help-text-soft); font-size: 12px; line-height: 1.5; margin: 4px 0; }

.help-operation-step a { font-size: 12px; font-weight: 600; }

.help-operation-video h2 { border: 0; font-size: 18px; margin: 0 0 8px; padding: 0; }

.help-operation-video video { background: var(--help-text-strong); border-radius: var(--help-media-radius); display: block; height: auto; margin-inline: auto; max-height: var(--help-video-max-height); max-width: min(100%, var(--help-video-max-width)); object-fit: contain; width: auto; }
.help-operation-video video:fullscreen { border-radius: 0; height: 100%; max-height: none; max-width: none; width: 100%; }

.help-index-list { list-style: none; margin: 20px 0 0; padding: 0; }

.help-index-group + .help-index-group { margin-top: 32px; }

.help-index-group h2 { border: 0; font-size: 18px; margin: 0; padding: 0; }

.help-index-list li + li { border-top: 1px solid var(--help-line); }

.help-index-list a { display: grid; gap: 4px; padding: 14px 0; text-decoration: none; }

.help-index-list a span { color: var(--help-text-soft); font-size: 13px; font-weight: 400; line-height: 1.6; }

.help-meta { color: var(--help-text-soft); font-size: 12px; margin: 0 0 20px; }

.help-footer { color: var(--help-text-soft); font-size: 12px; padding: 0 0 24px; }

@media (max-width: 900px) {
  .help-layout { grid-template-columns: 1fr; }
  .help-nav { display: none; }
  .help-operation-flow { grid-template-columns: 1fr; }
  .help-operation-step:not(:last-child)::after { bottom: -24px; right: 50%; top: auto; transform: rotate(90deg) translateX(-50%); }
}

@media (max-width: 640px) {
  .help-header,
  .help-main,
  .help-footer { width: min(100% - 24px, 1120px); }
  .help-article { padding: 20px 16px; }
  .help-article h1 { font-size: 26px; }
}