/* リセット */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: Arial, sans-serif;
  line-height: 1.5;
  padding: 20px;
  background: #f5f5f5;
  color: #333;
}

header {
  text-align: center;
  padding: 20px 0;
}

nav a {
  margin: 0 10px;
  text-decoration: none;
  color: #007acc;
}

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

section {
  margin: 40px 0;
}

.project-list {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
}

.project-card {
  background: #fff;
  padding: 15px;
  border-radius: 10px;
  flex: 1 1 250px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.1);
  text-align: center;
}

.project-card img {
  width: 100%;
  border-radius: 5px;
}

footer {
  text-align: center;
  margin-top: 40px;
  font-size: 0.9em;
}