/* Basic, readable, no-frills typography */
:root{
  --bg: #ffffff;
  --text: #111111;
  --muted: #444444;
  --rule: #e6e6e6;
  --max: 820px;
}

*{ box-sizing: border-box; }

html, body{
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.65;
}

.container{
  max-width: var(--max);
  margin: 0 auto;
  padding: 24px 18px;
}

.site-header{
  border-bottom: 1px solid var(--rule);
}

.site-header h1{
  margin: 0;
  font-size: 1.9rem;
  letter-spacing: -0.01em;
}

.letter{
  padding: 10px 0 40px;
}

.letter p{
  margin: 0 0 16px;
  font-size: 1.05rem;
}

.site-footer{
  border-top: 1px solid var(--rule);
  color: var(--muted);
}

small{
  font-size: 0.9rem;
}
@media (max-width: 520px){
  .site-header h1{ font-size: 1.55rem; }
  .letter p{ font-size: 1.02rem; }
}