/* General reset */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: Arial, sans-serif;
  line-height: 1.6;
  color: #333;
  background-color: #f9f9f9;
  padding: 0 20px;
  transition: background 0.3s ease, color 0.3s ease;
}

/* Dark Mode */
body.dark {
  background-color: #1c1c1c;
  color: #eaeaea;
}

body.dark header {
  background: #2d2d2d;
}

body.dark section h2 {
  border-bottom: 2px solid #ffcc00;
}

body.dark .project-card {
  background: #2a2a2a;
  box-shadow: 0 2px 6px rgba(255,255,255,0.1);
}

body.dark a {
  color: #ffcc00;
}

/* Toggle Button */
#theme-toggle {
  position: fixed;
  top: 15px;
  right: 20px;
  padding: 8px 12px;
  margin-right: 2%;
  border: none;
  background: #4a90e2;
  color: white;
  font-size: 14px;
  border-radius: 5px;
  cursor: pointer;
  z-index: 1000;
  border: 1px solid #2d2d2d;
  transition: background 0.3s ease;
}

#theme-toggle:hover {
  background: #357abd;
}

/* Header */
header {
  text-align: center;
  padding: 50px 0;
  background: #4a90e2;
  color: #fff;
  transition: background 0.3s ease;
}

header h1 {
  font-size: 2.5em;
}

header p {
  margin-top: 10px;
  font-size: 1.2em;
}

/* Section headings */
section {
  margin: 40px auto;
  max-width: 900px;
}

section h2 {
  margin-bottom: 20px;
  font-size: 1.8em;
  border-bottom: 2px solid #4a90e2;
  display: inline-block;
  padding-bottom: 5px;
  transition: border-color 0.3s ease;
}

/* Projects */
.project-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 20px;
}

.project-card {
  background: #fff;
  padding: 20px;
  border-radius: 10px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.1);
  transition: background 0.3s ease, box-shadow 0.3s ease;
}

.project-card h3 {
  margin-bottom: 10px;
  color: #4a90e2;
}

.project-card a {
  display: inline-block;
  margin-top: 10px;
  color: #4a90e2;
  text-decoration: none;
  font-weight: bold;
}

.project-card a:hover {
  text-decoration: underline;
}

/* Footer */
footer {
  text-align: center;
  margin: 50px 0 20px;
  color: #555;
}

footer a {
  color: #4a90e2;
  text-decoration: none;
}

footer a:hover {
  text-decoration: underline;
}