/* 全局样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: #f5f5f5;
    color: #333;
    line-height: 1.6;
}

/* 容器样式 */
.container {
    max-width: 600px;
    margin: 20px auto;
    padding: 0 15px;
}

/* 支付盒子样式 */
.payment-box {
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.1);
    padding: 25px;
    margin-top: 20px;
}

/* 标题样式 */
.title {
    text-align: center;
    color: #333;
    font-size: 24px;
    margin-bottom: 25px;
    font-weight: 600;
}

h2 {
    font-size: 18px;
    color: #666;
    margin-bottom: 15px;
    font-weight: 500;
}

/* 预设金额按钮区域 */
.preset-amounts {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
    gap: 12px;
    margin-bottom: 20px;
}

/* 金额按钮样式 */
.amount-btn {
    background: #f8f9fa;
    border: 2px solid #e9ecef;
    border-radius: 8px;
    padding: 12px;
    font-size: 16px;
    color: #495057;
    cursor: pointer;
    transition: all 0.3s ease;
}

.amount-btn:hover {
    background: #e9ecef;
    border-color: #dee2e6;
}

.amount-btn.active {
    background: #28a745;
    border-color: #28a745;
    color: white;
}

/* 自定义金额输入区域 */
.custom-amount {
    position: relative;
    margin-bottom: 25px;
}

.amount-input {
    width: 100%;
    padding: 12px 15px 12px 30px;
    font-size: 16px;
    border: 2px solid #e9ecef;
    border-radius: 8px;
    outline: none;
    transition: border-color 0.3s ease;
}

.amount-input:focus {
    border-color: #28a745;
}

.currency-symbol {
    position: absolute;
    left: 12px;
    top: 50%;
    transform: translateY(-50%);
    color: #666;
}

/* 支付按钮区域 */
.payment-action {
    text-align: center;
}

.pay-btn {
    background: #28a745;
    color: white;
    border: none;
    border-radius: 8px;
    padding: 15px 40px;
    font-size: 18px;
    cursor: pointer;
    transition: background-color 0.3s ease;
    width: 100%;
}

.pay-btn:hover {
    background: #218838;
}

/* 响应式适配 */
@media (max-width: 480px) {
    .container {
        margin: 10px auto;
    }
    
    .payment-box {
        padding: 20px;
    }
    
    .preset-amounts {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .title {
        font-size: 20px;
    }
    
    .amount-btn {
        padding: 10px;
        font-size: 14px;
    }
}