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

body {
    font-family: 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
}

header {
    background: #000000;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    padding: 1rem;
  
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
}

nav ul {
    display: flex;
    list-style: none;
}

nav ul li a {
    padding: 0.5rem 1rem;
    text-decoration: none;
    color: #ffffff;
}

.hero {
    text-align: center;
    padding: 4rem 2rem;
    background: #ffffff;
}

.cta-button {
    display: inline-block;
    padding: 1rem 2rem;
    background: #007bff;
    color: white;
    text-decoration: none;
    border-radius: 5px;
    margin-top: 2rem;
}

footer {
    text-align: center;
    padding: 2rem;
    background: #333;
    color: white;
}

.logo img {
    width: 3rem;  /* 相对于根元素字体大小 */
    height: 3rem;
}

.background {
    width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    margin: 0 auto;
}

.background img {
    width: 35%;
    height: auto;
    max-width: 1200px;
    display: block;
    margin: 2rem auto;
}