:root {
  --bg: #1e1e1e;
  --text: #f4f4f4;
  --accent: #6ee7b7;
  --muted: #aaa;
}
body.light {
  --bg: #f9f9f9;
  --text: #1a1a1a;
  --accent: #2563eb;
  --muted: #666;
}
body {
  background-color: var(--bg);
  color: var(--text);
  font-family: 'Manrope', sans-serif;
  margin: 0;
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  transition: background-color 0.3s ease, color 0.3s ease;

  /* More visible PCB-inspired background */
  background-image:
    url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='500' height='500' viewBox='0 0 500 500' preserveAspectRatio='xMidYMid meet'><style>line, path, circle {stroke:currentColor; stroke-width:1.5; opacity:0.2; fill:none;} circle {fill:currentColor; opacity:0.25;} text {fill:currentColor; font-family:sans-serif; font-weight:bold; font-size:10px; opacity:0.12;}</style><line x1='20' y1='20' x2='480' y2='20'/><line x1='20' y1='480' x2='480' y2='480'/><line x1='20' y1='20' x2='20' y2='480'/><line x1='480' y1='20' x2='480' y2='480'/><path d='M 50 50 L 150 50 L 150 150 L 250 150' stroke-linejoin='round'/><path d='M 350 350 L 350 250 L 250 250' stroke-linejoin='round'/><circle cx='50' cy='50' r='4'/><circle cx='150' cy='50' r='3'/><circle cx='150' cy='150' r='3'/><circle cx='250' cy='150' r='4'/><circle cx='350' cy='350' r='4'/><circle cx='350' cy='250' r='3'/><circle cx='250' cy='250' r='3'/><text x='40' y='40'>101</text><text x='140' y='60'>010</text><text x='230' y='140'>110</text><text x='260' y='160'>001</text><text x='340' y='260'>100</text><text x='360' y='340'>011</text></svg>");
  background-repeat: repeat;
  background-size: 500px 500px;
}

main {
  text-align: center;
  max-width: 640px;
  padding: 2rem;
}
h1 {
  font-size: 2.4rem;
  font-weight: 800;
  margin-bottom: 0.3rem;
}
p.subtitle {
  font-size: 1.1rem;
  color: var(--muted);
  margin-bottom: 2rem;
}
nav {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-bottom: 2rem;
}
nav a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
  font-size: 1.05rem;
  transition: all 0.2s ease;
}
nav a:hover {
  transform: translateX(4px);
}
.bullet {
  margin-right: 0.5rem;
  color: var(--accent);
  font-weight: 700;
}
.socials a {
  margin: 0 0.5rem;
  font-size: 1.3rem;
  text-decoration: none;
  color: var(--text);
  opacity: 0.7;
  transition: opacity 0.2s ease;
}
.socials a:hover {
  opacity: 1;
}
.theme-toggle {
  position: absolute;
  top: 1rem;
  right: 1rem;
  background: transparent;
  border: none;
  font-size: 1.2rem;
  color: var(--accent);
  cursor: pointer;
}