:root {
  --bg: #f4f6f8;
  --surface: rgba(255, 255, 255, 0.9);
  --text: #13212d;
  --muted: #586574;
  --line: rgba(19, 33, 45, 0.12);
  --accent: #0f766e;
  --accent-strong: #115e59;
  --shadow: 0 24px 60px rgba(19, 33, 45, 0.12);
  --radius-lg: 24px;
  --container: 1160px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Noto Sans JP", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(15, 118, 110, 0.14), transparent 30%),
    radial-gradient(circle at top right, rgba(20, 83, 45, 0.12), transparent 28%),
    linear-gradient(180deg, #f9fbfb 0%, var(--bg) 100%);
}

a {
  color: var(--accent-strong);
}

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

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(18px);
  background: rgba(244, 246, 248, 0.72);
  border-bottom: 1px solid rgba(19, 33, 45, 0.08);
}

.site-header__inner,
.site-footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 16px 0;
}

.site-brand {
  font-size: 1rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-decoration: none;
  color: var(--text);
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
}

.site-nav a,
.site-footer a {
  text-decoration: none;
  color: var(--muted);
}

.site-nav a:hover,
.site-footer a:hover {
  color: var(--accent-strong);
}

.page-main {
  padding: 46px 0;
}

.page-card {
  background: var(--surface);
  border: 1px solid rgba(255, 255, 255, 0.6);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: clamp(20px, 3.5vw, 44px);
}

.markdown-body h1,
.markdown-body h2,
.markdown-body h3 {
  line-height: 1.3;
  margin-top: 1.3em;
  margin-bottom: 0.5em;
}

.markdown-body h1 {
  font-size: clamp(1.9rem, 4vw, 2.6rem);
  margin-top: 0;
}

.markdown-body h2 {
  font-size: clamp(1.4rem, 2.7vw, 1.9rem);
  padding-bottom: 0.3em;
  border-bottom: 1px solid var(--line);
}

.markdown-body p,
.markdown-body li {
  line-height: 1.85;
}

.markdown-body ul,
.markdown-body ol {
  padding-left: 1.5em;
}

.markdown-body blockquote {
  margin: 1em 0;
  padding: 0.5em 1em;
  border-left: 4px solid rgba(15, 118, 110, 0.35);
  background: rgba(15, 118, 110, 0.06);
}

.markdown-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.2em 0;
}

.markdown-body th,
.markdown-body td {
  border: 1px solid var(--line);
  padding: 10px 12px;
  text-align: left;
}

.markdown-body tr:nth-child(even) {
  background: rgba(19, 33, 45, 0.03);
}

.site-footer {
  margin-top: 18px;
  border-top: 1px solid rgba(19, 33, 45, 0.08);
}

.site-footer p {
  margin: 0;
  color: var(--muted);
}

@media (max-width: 720px) {
  .container {
    width: min(calc(100% - 28px), var(--container));
  }

  .site-header__inner,
  .site-footer__inner {
    display: block;
  }

  .site-nav {
    margin-top: 12px;
    gap: 14px;
  }
}