* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg: #f8fafc;
  --bg-card: #ffffff;
  --text: #1e293b;
  --text-muted: #64748b;
  --link: #4f46e5;
  --border: #e2e8f0;
  --frontend: #0ea5e9;
  --backend: #f59e0b;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f172a;
    --bg-card: #1e293b;
    --text: #f1f5f9;
    --text-muted: #94a3b8;
    --link: #818cf8;
    --border: #334155;
  }
}

body {
  font-family: "Inter", sans-serif;
  line-height: 1.6;
  color: var(--text);
  background-color: var(--bg);
  padding: 20px;
}

header {
  max-width: 800px;
  margin: 0 auto 40px;
  text-align: center;
  padding-bottom: 30px;
  border-bottom: 2px solid var(--border);
  & h1 {
    font-weight: 700;
    font-size: 2rem;
    margin-bottom: 10px;
  }
  & p {
    font-size: 1rem;
    color: var(--text-muted);
  }
}

main {
  max-width: 800px;
  margin: 0 auto;
}

section {
  margin-bottom: 40px;
  & h2 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 20px;
  }
  & article {
    margin-bottom: 20px;
    padding: 15px;
    background-color: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 8px;
    & h3 {
      font-size: 1.2rem;
      margin-bottom: 10px;
      & span {
        color: var(--text-muted);
      }
    }
    & p {
      margin-bottom: 10px;
      color: var(--text-muted);
    }
    & ul {
      display: flex;
      gap: 15px;
      & li {
        display: inline;
        & span {
          color: var(--text-muted);
          cursor: not-allowed;
          pointer-events: none;
        }
      }
    }
  }
  &.frontend article {
    border-left: 6px solid var(--frontend);
  }
  &.backend article {
    border-left: 6px solid var(--backend);
  }
}

a {
  color: var(--link);
  text-decoration: none;
  &:not(h1 a):hover {
    text-decoration: underline;
  }
}

footer {
  text-align: center;
  margin-top: 60px;
  padding-top: 20px;
  border-top: 2px solid var(--border);
  color: var(--text-muted);
  font-size: 0.9rem;
}