body.dark {
  background: #181818;
  color: #ededed;
  font-family: 'Segoe UI', Arial, sans-serif;
}
nav.sidebar {
  position: fixed;
  left: 0;
  top: 0;
  width: 220px;
  height: 100vh;
  background: #222;
  padding: 30px 0 0 0;
}
nav.sidebar ul { list-style: none; padding: 0; }
nav.sidebar li { margin-bottom: 30px; }
nav.sidebar a { color: #a9b7c6; text-decoration: none; font-size: 1.2em; }
.main-content {
  margin-left: 230px;
  padding: 40px 20px;
  min-height: 100vh;
}
.intro h1 { font-size: 2.5rem; }
.project-card {
  background: #242424;
  border-radius: 10px;
  margin: 15px;
  padding: 20px;
  min-height: 350px;
  box-shadow: 0 0 10px #0002;
}
.project-card img { max-width: 100%; display: block; margin-bottom: 8px; border-radius: 8px; }
@media (max-width: 700px) {
  nav.sidebar { width: 100%; height: auto; position: static; padding:0; }
  .main-content { margin-left: 0; }
}