:root {
  color-scheme: light;
  --font-sans: "Inter", "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "Fira Code", "SFMono-Regular", Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  --bg-color: #f8f9fb;
  --text-color: #1d1f23;
  --muted-text: #5f6570;
  --border-color: rgba(0, 0, 0, 0.08);
  --link-color: #0a66ff;
  --link-hover: #084ed6;
  --card-bg: rgba(255, 255, 255, 0.88);
  --shadow-sm: 0 12px 30px rgba(10, 17, 30, 0.06);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  background: var(--bg-color);
  color: var(--text-color);
  font-family: var(--font-sans);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

body {
  min-height: 100vh;
  background-image: radial-gradient(rgba(96, 125, 255, 0.08) 1px, transparent 1px);
  background-size: 36px 36px;
}

a {
  color: var(--link-color);
  text-decoration: none;
  transition: color 0.2s ease-in-out;
}

a:hover,
a:focus-visible {
  color: var(--link-hover);
  text-decoration: underline;
}

main,
header,
footer {
  position: relative;
  z-index: 1;
}

header,
footer {
  background: var(--card-bg);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
}

footer {
  border-top: 1px solid var(--border-color);
  border-bottom: none;
}

ul,
ol {
  padding-inline-start: 1.4rem;
}

code,
pre,
kbd,
samp {
  font-family: var(--font-mono);
}

blockquote {
  margin: 1.5rem 0;
  padding: 0.95rem 1.2rem;
  border-inline-start: 4px solid var(--link-color);
  background: rgba(10, 102, 255, 0.08);
  border-radius: 8px;
  color: var(--muted-text);
}

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

article {
  background: var(--card-bg);
  border-radius: 18px;
  padding: 2rem clamp(1.25rem, 4vw, 3rem);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-color);
}

article h1,
article h2,
article h3,
article h4 {
  font-weight: 640;
  letter-spacing: 0.01em;
}

article h2 {
  margin-top: 2.2rem;
}

article h3 {
  margin-top: 1.8rem;
}

article p {
  margin: 1rem 0;
}

article table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  background: rgba(255, 255, 255, 0.03);
}

article th,
article td {
  padding: 0.75rem 1rem;
  border: 1px solid var(--border-color);
  text-align: left;
}

article tr:nth-child(odd) {
  background: rgba(0, 0, 0, 0.02);
}

.hr-divider {
  width: 100%;
  height: 1px;
  background: var(--border-color);
  margin: 2.5rem 0;
}

@media (max-width: 720px) {
  body {
    background-size: 28px 28px;
  }

  article {
    border-radius: 14px;
    padding: 1.75rem 1.1rem;
  }

  header,
  footer {
    text-align: center;
  }
}