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

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

header {
    background-color: #f8f9fa;
    padding: 1rem;
    text-align: center;
    border-bottom: 1px solid #ddd;
}

nav {
    margin: 1rem 0;
}

nav a {
    margin: 0 1rem;
    text-decoration: none;
    color: #007bff;
}

nav a:hover {
    color: #0056b3;
}

main {
    max-width: 800px;
    margin: 2rem auto;
    padding: 0 1rem;
}

section {
    margin-bottom: 2rem;
}

h1, h2, h3 {
    margin-bottom: 1rem;
}

ul {
    margin-left: 2rem;
    margin-bottom: 1rem;
}

p {
    margin-bottom: 1rem;
}

footer {
    text-align: center;
    padding: 1rem;
    background-color: #f8f9fa;
    border-top: 1px solid #ddd;
    position: fixed;
    bottom: 0;
    width: 100%;
}

.support-section, .privacy-section {
    background-color: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

@media (max-width: 600px) {
    main {
        padding: 0 0.5rem;
    }
    
    .support-section, .privacy-section {
        padding: 1rem;
    }
}

.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.feature-group {
    background: #f8f9fa;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.feature-group h4 {
    color: #2c3e50;
    margin-bottom: 1rem;
}

.support-section strong {
    color: #2c3e50;
    display: block;
    margin-top: 1.5rem;
}

.support-section li p {
    margin-top: 0.5rem;
    color: #666;
}