:root {
    --primary-color: #27ae60;
    --primary-dark: #219a52;
    --secondary-color: #2ecc71;
    --dark-color: #2c3e50;
    --light-color: #f8f9fa;
    --gradient-primary: linear-gradient(135deg, #27ae60, #2ecc71);
    --gradient-dark: linear-gradient(135deg, #2c3e50, #34495e);
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--dark-color);
    overflow-x: hidden;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-header h2 {
    font-size: 2.5rem;
    color: var(--dark-color);
    margin-bottom: 1rem;
}

.section-header p {
    color: #666;
    font-size: 1.2rem;
}

/* 通用按钮样式 */
.btn {
    padding: 0.8rem 2rem;
    border-radius: 50px;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    font-size: 1rem;
}

.btn-primary {
    background: transparent;
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(39, 174, 96, 0.3);
}

/* 页面过渡动画 */
.page-transition {
    opacity: 0;
    animation: fadeIn 0.5s ease forwards;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}