.mailbox {
    width: 1200px;
    margin: 30px auto;
    border-radius: 5px;
    box-shadow: 0 0 10px 0 rgba(0, 0, 0, .2);
    box-sizing: border-box;
    padding: 70px;
}

.mailbox .title {
    font-size: 24px;
    text-align: center;
    padding-bottom: 30px;
    font-weight: bold;
    color: #a01f19;
}

.form {
    width: 600px;
    margin: auto;
}

.form_item {
    display: flex;
    align-items: center;
    margin-bottom: 20px;
}

.form_item .label {
    width: 100px;
    font-size: 18px;
    padding-right: 10px;
    text-align: right;
}

.form_item .input {
    width: 400px;
    height: 38px;
    border-radius: 3px;
    border: 1px solid #ccc;
    padding: 0 10px;
    box-sizing: border-box;
    outline: none;
    font-size: 18px;
}

.form_item .textarea {
    width: 400px;
    height: 100px;
    border: 1px solid #ccc;
    padding: 10px;
    box-sizing: border-box;
    color: #000;
    outline: none;
    font-size: 18px;
    font-family: '微软雅黑';
}
.form__btu{
    width: 400px;
    height: 44px;
    background-color: #a01f19;
    color: #fff;
    font-size: 18px;
    border: 0;
    border-radius: 3px;
    margin-left: 110px;
}

.form_tip {
    height: 20px;
    padding: 10px;
    color: #a01f19;
    text-align: center;
}