/* 基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

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

a {
    color: #667eea;
    text-decoration: none;
    transition: color 0.3s;
}

a:hover {
    color: #764ba2;
}

button, input, textarea, select {
    font-family: inherit;
    font-size: inherit;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 按钮样式 */
.btn {
    display: inline-block;
    padding: 10px 20px;
    border-radius: 6px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s;
    border: none;
    text-align: center;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(102, 126, 234, 0.3);
}

.btn-secondary {
    background: #f0f0f0;
    color: #333;
}

.btn-secondary:hover {
    background: #e0e0e0;
}

.btn-success {
    background: #2ecc71;
    color: white;
}

.btn-success:hover {
    background: #27ae60;
}

.btn-danger {
    background: #e74c3c;
    color: white;
}

.btn-danger:hover {
    background: #c0392b;
}

/* 表单样式 */
.form-group {
    margin-bottom: 20px;
}

.form-label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
}

.form-control {
    width: 100%;
    padding: 12px;
    border: 2px solid #e1e5e9;
    border-radius: 8px;
    font-size: 16px;
    transition: border-color 0.3s;
}

.form-control:focus {
    border-color: #667eea;
    outline: none;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

/* 卡片样式 */
.card {
    background: white;
    border-radius: 12px;
    padding: 25px;
    box-shadow: 0 6px 15px rgba(0, 0, 0, 0.08);
    margin-bottom: 20px;
}

/* 工具类 */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-left { text-align: left; }

.mt-1 { margin-top: 10px; }
.mt-2 { margin-top: 20px; }
.mt-3 { margin-top: 30px; }
.mt-4 { margin-top: 40px; }

.mb-1 { margin-bottom: 10px; }
.mb-2 { margin-bottom: 20px; }
.mb-3 { margin-bottom: 30px; }
.mb-4 { margin-bottom: 40px; }

.hidden { display: none; }

/* 动画 */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.fade-in {
    animation: fadeIn 0.6s ease-out;
}

/* 响应式 */
@media (max-width: 768px) {
    .container {
        padding: 0 15px;
    }
    
    .card {
        padding: 20px;
    }
}