html, body {
    background-color:#FFFFFF;
    width: 100%;
    min-height: 100vh;
    font-family:Arial, sans-serif;
    font-size: 20px;
    padding: 0;
    margin: 0;
    cursor: default;
}

.main {
     position: absolute;
     top: 50%;
     left: 50%;
     width: 291px;
     height: 58px;
     padding: 0;
     margin-left: -145px;
     margin-top: -29px;
     background: #fff;
     box-sizing: border-box;
}

.a1 {
    min-width: 291px;
    min-height: 58px;
    padding: 0;
    background: #fff;
    text-align: center;
    font-size: 25px;
}

.a2 {
    min-width: 291px;
    min-height: 58px;
    padding: 0;
    background: #fff;
    text-align: center;
    font-size: 30px;
    font-weight: bold;
}

img {
    display: block;
    width: 291px;
    min-width: 291px;
    height: 58px;
    min-height: 58px;
}