* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Poppins", sans-serif;
  transition: background 0.3s, color 0.3s;
}
body { line-height: 1.6; scroll-behavior: smooth; }
.light { background: #f5f7fa; color: #222; }
.dark { background: #0d1117; color: #e6edf3; }
#loader {
  position: fixed; inset: 0; display: flex; justify-content: center; align-items: center;
  background: #0d1117; z-index: 9999; transition: opacity 0.8s;
}
.light #loader { background: #fff; }
.typewriter h2 {
  overflow: hidden; border-right: 3px solid #58a6ff; white-space: nowrap;
  animation: typing 1.5s steps(30) 1, blink 0.8s infinite; color: #58a6ff;
}
@keyframes typing { from { width: 0; } to { width: 100%; } }
@keyframes blink { 50% { border-color: transparent; } }
header { position: sticky; top: 0; z-index: 999; }
.navbar { display: flex; justify-content: space-between; align-items: center; padding: 15px 40px; backdrop-filter: blur(6px); }
.light .navbar { background: rgba(255,255,255,0.9); border-bottom: 1px solid #ddd; }
.dark .navbar { background: rgba(22,27,34,0.9); border-bottom: 1px solid #30363d; }
.navbar a { color: inherit; text-decoration: none; margin-left: 20px; font-weight: 500; }
.navbar a:hover { color: #ff6600; }
#theme-toggle { background: none; border: none; font-size: 1.5rem; cursor: pointer; margin-left: 15px; }
#hero { text-align: center; padding: 120px 20px; }
.light #hero { background: linear-gradient(135deg, #004a99, #007bff); color: white; }
.dark #hero { background: linear-gradient(135deg, #161b22, #0d1117); color: #e6edf3; }
#hero h1 { font-size: 2.5rem; margin-bottom: 10px; }
#hero h1 span { color: #ffcc00; }
#hero p { font-size: 1.3rem; margin-bottom: 30px; }
.btn { background: #ff6600; color: white; padding: 10px 25px; border-radius: 30px; text-decoration: none; transition: 0.3s; }
.btn:hover { background: #ffaa00; }
.dark .btn { background: #238636; }
.dark .btn:hover { background: #2ea043; }
.content { padding: 60px 20px; max-width: 1000px; margin: auto; text-align: center; }
h2 { font-size: 2rem; margin-bottom: 20px; }
.projects { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 20px; }
.project-card { border-radius: 10px; padding: 30px; text-decoration: none; transition: transform 0.3s, box-shadow 0.3s; }
.light .project-card { background: white; color: #333; box-shadow: 0 2px 5px rgba(0,0,0,0.1); }
.light .project-card:hover { transform: translateY(-5px); box-shadow: 0 5px 15px rgba(0,0,0,0.2); color: #004a99; }
.dark .project-card { background: #161b22; color: #e6edf3; box-shadow: 0 2px 5px rgba(0,0,0,0.5); }
.dark .project-card:hover { background: #21262d; transform: translateY(-5px); color: #58a6ff; }
.contact {
  list-style: none; display: flex; justify-content: center; flex-wrap: wrap;
  gap: 30px; margin-top: 25px; padding: 0; text-align: center;
}
.contact li { margin: 0; font-size: 1rem; display: flex; align-items: center; gap: 6px; }
.contact strong { color: #ff6600; margin-right: 3px; }
.contact a { color: inherit; text-decoration: none; transition: color 0.3s; }
.contact a:hover { color: #007bff; text-decoration: underline; }
@media (max-width: 600px) { .contact { flex-direction: column; align-items: center; gap: 10px; } }
footer { text-align: center; padding: 20px; font-size: 0.9rem; margin-top: 50px; }
.light footer { background: #003366; color: #fff; }
.dark footer { background: #161b22; color: #8b949e; border-top: 1px solid #30363d; }
/* Sayfa geçiş efekti */
.transition-overlay {
  position: fixed; inset: 0; display: flex; align-items: center; justify-content: center;
  background: #0d1117; z-index: 9999; transition: opacity 0.8s;
}
.light .transition-overlay { background: #ffffff; }
.transition-overlay .typewriter h2 {
  overflow: hidden; border-right: 3px solid #58a6ff; white-space: nowrap;
  animation: typing 1.5s steps(30) 1, blink 0.8s infinite; color: #58a6ff;
}