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

body {
  font-family: "Microsoft YaHei", sans-serif;
  background: #f5f7fa;
  color: #333;
  line-height: 1.6;
}

.hero {
  height: 100vh;
  background: url("../images/1.webp") center/cover no-repeat;
  position: relative;
}

.overlay {
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.45);
  color: #fff;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 20px;
  text-align: center;
}

.overlay h1 {
  font-size: 48px;
}

.overlay p {
  font-size: 20px;
}

.btn {
  display: inline-block;
  padding: 12px 28px;
  background: #4da3ff;
  color: #fff;
  text-decoration: none;
  border-radius: 8px;
}

section {
  padding: 60px 10%;
}

section h2 {
  text-align: center;
  margin-bottom: 30px;
  font-size: 32px;
}

.intro p,
.about p {
  max-width: 900px;
  margin: 10px auto;
  text-align: center;
  font-size: 18px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 24px;
}

.card {
  background: #fff;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.08);
}

.card img {
  width: 100%;
  height: 220px;
  object-fit: cover;
  display: block;
}

.card p {
  padding: 14px;
  text-align: center;
}

footer {
  text-align: center;
  padding: 20px;
  background: #111;
  color: #fff;
}