:root {
  --text: #111;
  --muted: #555;
  --border: #e6e6e6;
  --bg: #fff;
  --link: #0b57d0;
  --max: 900px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.6;
}

header, main, footer {
  width: min(var(--max), calc(100% - 32px));
  margin: 0 auto;
}

header { padding: 28px 0 10px; }
main { padding: 8px 0 36px; }
footer { padding: 20px 0 40px; }

h1 { margin: 0 0 8px; font-size: 40px; letter-spacing: -0.02em; }
h2 { margin: 24px 0 10px; font-size: 24px; }
h3 { margin: 18px 0 8px; font-size: 18px; }

p { margin: 0 0 12px; color: var(--text); }
nav { margin: 8px 0 10px; }

a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; }

hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 18px 0;
}

section { padding: 6px 0; }

ul { margin: 8px 0 14px 18px; }
li { margin: 2px 0; color: var(--muted); }

header p, header nav { color: var(--muted); }

section {
  margin-bottom: 32px;
}

article {
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: #fafafa;
}

nav a {
  font-weight: 500;
}

h2 {
  border-bottom: 1px solid var(--border);
  padding-bottom: 6px;
}

.skills-grid{
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-top: 12px;
}

.skill-card{
  padding: 14px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: #fff;
}

.skill-card h3{
  margin-top: 0;
}

.skill-card ul{
  margin: 8px 0 0 18px;
}

@media (max-width: 800px){
  .skills-grid{
    grid-template-columns: 1fr;
  }
}