style3.css

body{
    margin: 0;
    padding: 0;
    font-family:sans-serif;
    background-size:cover;
    background: url(..//nature_scenes_3-wallpaper-3840x2160.jpg) no-repeat;
}

.login-box{
    width: 280px;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%,-50%);
    color: #fff;
}
.login-box h1{
    float: left;
    font-size: 40px;
    border-bottom: 6px solid #1e0f64;
    margin-bottom: 50px;
    padding: 13px 0;
}
.text-box{
    width: 100%;
    overflow: hidden;
    font-size: 20px;
    padding: 8px 0;
    margin: 8px 0;
    border-bottom: 1px solid #1e0f64;
}
.text-box i{
    width: 26px;
    float: left;
    text-align: center;
}
.text-box input{
    border: none;
    outline: none;
    background: none;
    color: #fff;
    font-size: 18px;
    width: 80%;
    float: left;
    margin: 0 10px;
    width: 80%;
}
.btn{
    width: 100%;
    background: none;
    border: 2px solid #1e0f64;
    color: #e3e0ee;
    padding: 5px;
    font-size: 20px;
    cursor: pointer;
    margin: 12px 0;
}