/* Apple Design System inspired styling */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #1d1d1f;
    background: #f5f5f7;
    font-size: 17px;
}

/* Header */
header {
    background: #fff;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

nav {
    max-width: 980px;
    margin: 0 auto;
    padding: 0 20px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    font-size: 21px;
    font-weight: 600;
    color: #1d1d1f;
    text-decoration: none;
}

.lang-switch {
    display: flex;
    gap: 8px;
    font-size: 14px;
}

.lang-switch a {
    color: #424245;
    text-decoration: none;
    padding: 4px 8px;
    border-radius: 4px;
    transition: background-color 0.2s;
}

.lang-switch a:hover {
    background: #f5f5f7;
}

.lang-switch a.active {
    color: #007aff;
    font-weight: 600;
}

/* Main Content */
main {
    max-width: 980px;
    margin: 40px auto;
    padding: 0 20px;
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.en-content,
.zh-content {
    padding: 48px 40px;
}

h1 {
    font-size: 40px;
    font-weight: 600;
    color: #1d1d1f;
    margin-bottom: 8px;
    line-height: 1.1;
}

h2 {
    font-size: 28px;
    font-weight: 600;
    color: #1d1d1f;
    margin-top: 48px;
    margin-bottom: 16px;
}

h3 {
    font-size: 21px;
    font-weight: 600;
    color: #1d1d1f;
    margin-top: 32px;
    margin-bottom: 12px;
}

p {
    margin-bottom: 16px;
    color: #424245;
}

em {
    color: #6e6e73;
    font-style: italic;
}

ul, ol {
    margin-left: 24px;
    margin-bottom: 16px;
}

li {
    margin-bottom: 8px;
    color: #424245;
}

strong {
    font-weight: 600;
    color: #1d1d1f;
}

a {
    color: #007aff;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

code {
    background: #f5f5f7;
    padding: 2px 6px;
    border-radius: 4px;
    font-family: 'SF Mono', Monaco, 'Courier New', monospace;
    font-size: 0.9em;
    color: #d73a49;
}

/* FAQ Cards */
.faq-section {
    margin-top: 32px;
}

.faq-item {
    background: #f5f5f7;
    border-radius: 8px;
    padding: 20px;
    margin-bottom: 16px;
    transition: box-shadow 0.2s;
}

.faq-item:hover {
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.faq-question {
    font-size: 19px;
    font-weight: 600;
    color: #1d1d1f;
    margin-bottom: 8px;
}

.faq-answer {
    color: #424245;
}

/* Contact Section */
.contact-info {
    background: #f5f5f7;
    border-radius: 8px;
    padding: 24px;
    margin-top: 32px;
}

.contact-info h3 {
    margin-top: 0;
}

.contact-email {
    font-size: 19px;
    font-weight: 500;
    color: #007aff;
}

/* Footer */
footer {
    max-width: 980px;
    margin: 40px auto;
    padding: 20px;
    text-align: center;
    color: #6e6e73;
    font-size: 14px;
}

/* Responsive Design */
@media (max-width: 768px) {
    nav {
        padding: 0 16px;
    }

    .logo {
        font-size: 18px;
    }

    main {
        margin: 20px 16px;
        border-radius: 8px;
    }

    .en-content,
    .zh-content {
        padding: 32px 24px;
    }

    h1 {
        font-size: 32px;
    }

    h2 {
        font-size: 24px;
        margin-top: 32px;
    }

    h3 {
        font-size: 19px;
        margin-top: 24px;
    }

    .faq-item {
        padding: 16px;
    }

    .faq-question {
        font-size: 17px;
    }
}