:root {
  --ink: #14243a;
  --body: #2f4156;
  --muted: #68798b;
  --blue: #1f6288;
  --blue-deep: #113b56;
  --green: #28765d;
  --paper: #ffffff;
  --wash: #ffffff;
  --line: #dce5eb;
  --line-strong: #c5d4de;
  --panel: #ffffff;
  --shadow: 0 12px 30px rgba(20, 36, 58, 0.065);
  --hairline: rgba(220, 229, 235, 0.72);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: #ffffff;
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  line-height: 1.78;
  text-rendering: optimizeLegibility;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
}

a {
  color: inherit;
  text-decoration: none;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: center;
  gap: 26px;
  min-height: 70px;
  padding: 0 max(24px, calc((100vw - 1180px) / 2));
  border-bottom: 1px solid rgba(197, 212, 222, 0.74);
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(14px);
}

.brand {
  color: var(--blue-deep);
  font-size: 17px;
  font-weight: 900;
  letter-spacing: 0;
}

.nav {
  display: flex;
  justify-content: flex-end;
  gap: 4px;
  min-width: 0;
  overflow-x: auto;
  color: #405268;
  font-size: 14px;
  font-weight: 760;
  white-space: nowrap;
  scrollbar-width: thin;
}

.nav a {
  padding: 7px 9px;
  border-radius: 8px;
}

.nav a:hover {
  background: #eef4f7;
  color: var(--blue);
}

.markdown-page {
  width: min(1120px, calc(100% - 48px));
  margin: 0 auto;
}

.markdown-content {
  padding: 54px 0 96px;
}

.markdown-content > * {
  max-width: 1080px;
}

.markdown-content h1,
.markdown-content h2,
.markdown-content h3,
.markdown-content h4 {
  margin: 0;
  line-height: 1.24;
  letter-spacing: 0;
  text-wrap: balance;
}

.markdown-content h2 {
  position: relative;
  margin-top: 84px;
  padding-top: 32px;
  border-top: 1px solid var(--line);
  color: var(--blue-deep);
  font-size: clamp(30px, 2.8vw, 40px);
  font-weight: 900;
}

.markdown-content h2:first-of-type {
  margin-top: 0;
  padding-top: 0;
  border-top: 0;
}

.markdown-content h2::after {
  content: "";
  display: block;
  width: 64px;
  height: 3px;
  margin-top: 13px;
  border-radius: 999px;
  background: var(--green);
}

.markdown-content h3 {
  margin-top: 50px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--hairline);
  color: #18324a;
  font-size: 25px;
  font-weight: 860;
}

.markdown-content h3:has(+ ul) {
  margin-top: 42px;
  padding: 15px 20px;
  border: 1px solid var(--blue-deep);
  border-bottom: 0;
  border-radius: 8px 8px 0 0;
  background: var(--blue-deep);
  color: #fff;
  font-size: 21px;
}

.markdown-content h3:has(+ ul) + ul {
  margin-top: 0;
  border-radius: 0 0 8px 8px;
}

.markdown-content h4 {
  margin-top: 32px;
  color: var(--green);
  font-size: 22px;
  font-weight: 860;
}

.markdown-content h4 + p {
  margin-top: 10px;
  padding: 15px 18px;
  border-left: 4px solid var(--green);
  background: #ffffff;
}

.markdown-content p {
  margin: 20px 0 0;
  color: var(--body);
  font-size: 19px;
  line-height: 1.84;
  overflow-wrap: anywhere;
}

.markdown-content strong {
  color: #111f32;
  font-weight: 900;
}

.markdown-content em {
  font-style: normal;
}

.markdown-content ul,
.markdown-content ol {
  margin: 22px 0 0;
  padding: 23px 30px 23px 50px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
  color: var(--body);
  font-size: 17px;
  box-shadow: 0 6px 18px rgba(20, 36, 58, 0.035);
  overflow-wrap: anywhere;
}

.markdown-content li + li {
  margin-top: 13px;
  padding-top: 13px;
  border-top: 1px solid var(--hairline);
}

.markdown-content li p {
  margin: 0;
  font-size: 17px;
  line-height: 1.72;
}

.markdown-content p:has(> img) {
  margin: 32px 0 0;
  padding: 10px;
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  background: var(--paper);
  box-shadow: var(--shadow);
}

.markdown-content p:has(> img) img {
  width: 100%;
  border-radius: 5px;
}

@media (max-width: 920px) {
  .topbar {
    grid-template-columns: 1fr;
    gap: 8px;
    padding-top: 14px;
    padding-bottom: 12px;
  }

  .nav {
    justify-content: flex-start;
    width: 100%;
  }

  .markdown-content {
    padding-top: 44px;
  }
}

@media (max-width: 560px) {
  .markdown-page {
    width: min(100% - 28px, 1120px);
  }

  .brand {
    font-size: 16px;
  }

  .markdown-content h2 {
    font-size: 27px;
  }

  .markdown-content h3 {
    font-size: 21px;
  }

  .markdown-content h3:has(+ ul) {
    padding: 14px 15px;
    font-size: 19px;
  }

  .markdown-content h4 {
    font-size: 19px;
  }

  .markdown-content p {
    font-size: 16px;
    line-height: 1.78;
  }

  .markdown-content ul,
  .markdown-content ol {
    padding: 17px 15px 17px 28px;
  }

  .markdown-content p:has(> img) {
    padding: 8px;
  }
}