:root {
  color-scheme: light;
  --flow-bg: #f4f6f9;
  --flow-panel: #ffffff;
  --flow-text: #1d2430;
  --flow-muted: #647084;
  --flow-border: #d9e0ea;
  --flow-blue: #244783;
  --flow-green: #7ca51b;
  --flow-hover: #eef3fb;
  --flow-code: #182033;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--flow-bg);
  color: var(--flow-text);
  font-family: Arial, Helvetica, sans-serif;
}

.flow-page {
  display: grid;
  grid-template-columns: minmax(230px, 300px) minmax(0, 1fr);
  min-height: 100vh;
}

.flow-sidebar {
  position: sticky;
  top: 0;
  height: 100vh;
  overflow: auto;
  border-right: 1px solid var(--flow-border);
  background: #ffffff;
}

.flow-sidebar-head {
  padding: 20px 18px 14px;
  border-bottom: 1px solid var(--flow-border);
}

.flow-sidebar-head h1 {
  margin: 0;
  color: var(--flow-blue);
  font-size: 1.25rem;
  line-height: 1.2;
}

.flow-sidebar-head span {
  display: block;
  margin-top: 4px;
  color: var(--flow-muted);
  font-size: 0.86rem;
}

.flow-list {
  display: grid;
  gap: 4px;
  padding: 10px;
}

.flow-list button {
  width: 100%;
  padding: 10px 12px;
  border: 0;
  border-left: 3px solid transparent;
  border-radius: 6px;
  background: transparent;
  color: var(--flow-text);
  cursor: pointer;
  font: inherit;
  text-align: left;
}

.flow-list button:hover {
  background: var(--flow-hover);
}

.flow-list button[aria-current="page"] {
  border-left-color: var(--flow-green);
  background: #f2f7e8;
  color: #263b08;
  font-weight: 700;
}

.flow-main {
  min-width: 0;
  padding: 28px;
}

.flow-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 18px;
  max-width: 1180px;
  margin: 0 auto 18px;
}

.flow-kicker {
  margin: 0 0 4px;
  color: var(--flow-muted);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.flow-header h2 {
  margin: 0;
  color: var(--flow-blue);
  font-size: 1.75rem;
  line-height: 1.2;
}

.flow-source-link {
  flex: 0 0 auto;
  padding: 8px 12px;
  border: 1px solid var(--flow-border);
  border-radius: 6px;
  background: #fff;
  color: var(--flow-blue);
  text-decoration: none;
}

.flow-source-link:hover {
  border-color: var(--flow-blue);
}

.flow-content {
  max-width: 1180px;
  margin: 0 auto;
  padding: 26px;
  border: 1px solid var(--flow-border);
  border-radius: 8px;
  background: var(--flow-panel);
  box-shadow: 0 10px 24px rgba(24, 32, 51, 0.06);
  line-height: 1.6;
}

.flow-content h1,
.flow-content h2,
.flow-content h3,
.flow-content h4 {
  color: var(--flow-blue);
  line-height: 1.25;
}

.flow-content h1 {
  margin: 0 0 16px;
  font-size: 1.8rem;
}

.flow-content h2 {
  margin: 28px 0 10px;
  font-size: 1.28rem;
}

.flow-content p {
  margin: 0 0 14px;
}

.flow-content ul,
.flow-content ol {
  margin: 0 0 16px;
  padding-left: 24px;
}

.flow-content code {
  border-radius: 4px;
  background: #edf1f6;
  padding: 0.12em 0.3em;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 0.92em;
}

.flow-content pre {
  overflow: auto;
  margin: 0 0 18px;
  padding: 14px;
  border-radius: 6px;
  background: var(--flow-code);
  color: #f6f8fb;
}

.flow-content pre code {
  background: transparent;
  padding: 0;
  color: inherit;
}

.mermaid-wrap {
  overflow: auto;
  margin: 0 0 22px;
  padding: 18px;
  border: 1px solid #dbe4ef;
  border-radius: 8px;
  background: #fbfcfe;
}

.mermaid {
  min-width: 640px;
  text-align: center;
}

.flow-empty {
  color: var(--flow-muted);
}

@media (max-width: 800px) {
  .flow-page {
    grid-template-columns: 1fr;
  }

  .flow-sidebar {
    position: static;
    height: auto;
    max-height: 42vh;
    border-right: 0;
    border-bottom: 1px solid var(--flow-border);
  }

  .flow-main {
    padding: 18px 12px;
  }

  .flow-header {
    flex-direction: column;
  }

  .flow-content {
    padding: 18px;
  }
}