:root {
  color-scheme: light;
  --bg: #f7f8f5;
  --surface: #ffffff;
  --ink: #202522;
  --muted: #657168;
  --line: #dce3dc;
  --green: #2f7d55;
  --blue: #276eb5;
  --yellow: #f4c84f;
}

* {
  box-sizing: border-box;
}

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

a {
  color: var(--blue);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.wrap {
  width: min(1080px, calc(100% - 40px));
  margin: 0 auto;
}

.site-header {
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.95);
}

.header-inner {
  min-height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  color: var(--ink);
  font-weight: 700;
}

nav {
  display: flex;
  gap: 20px;
  font-size: 15px;
}

nav a {
  color: var(--muted);
}

.hero {
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(135deg, rgba(47, 125, 85, 0.16), rgba(39, 110, 181, 0.12)),
    #ffffff;
}

.hero-inner {
  min-height: 420px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 64px 0;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--green);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 760px;
  margin-bottom: 18px;
  font-size: clamp(34px, 6vw, 58px);
  line-height: 1.12;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 22px;
  font-size: 28px;
  line-height: 1.25;
}

h3 {
  margin-bottom: 10px;
  font-size: 20px;
}

.lead {
  max-width: 760px;
  margin-bottom: 0;
  color: var(--muted);
  font-size: 18px;
}

.section {
  padding: 64px 0;
}

.muted {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: #ffffff;
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.topic {
  min-height: 220px;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
}

.topic-label {
  margin-bottom: 12px;
  color: var(--green);
  font-size: 13px;
  font-weight: 700;
}

.topic p:last-child,
.about-box p:last-child {
  margin-bottom: 0;
}

.note-layout {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(280px, 1.1fr);
  gap: 48px;
  align-items: start;
}

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

.note-list li {
  margin-bottom: 12px;
  padding: 16px 18px;
  border-left: 4px solid var(--yellow);
  background: var(--bg);
}

.about-box {
  max-width: 860px;
}

.site-footer {
  border-top: 1px solid var(--line);
  background: #202522;
  color: #dfe6df;
}

.footer-inner {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  font-size: 14px;
}

.site-footer a {
  color: #dfe6df;
}

@media (max-width: 780px) {
  .wrap {
    width: min(100% - 28px, 1080px);
  }

  .header-inner,
  .footer-inner {
    align-items: flex-start;
    flex-direction: column;
    justify-content: center;
    padding: 14px 0;
  }

  nav {
    width: 100%;
    justify-content: space-between;
    gap: 12px;
  }

  .hero-inner {
    min-height: auto;
    padding: 48px 0;
  }

  .topic-grid,
  .note-layout {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 44px 0;
  }

  .topic {
    min-height: auto;
  }
}