* {
    margin: 0;
    padding: 0;
    text-decoration: none;
    font-family: Calibri;
    box-sizing: border-box;
}

body {
    min-height: 100vh;
    background: url(images/VAMA_bckg.jpg) no-repeat center center fixed;
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover;
}

.login-form {
    width: 360px;
    background: #f7f7f7;
    height: 450px;
    padding: 60px 40px;
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);

    -webkit-box-shadow: 10px 10px 89px -12px rgba(0,0,0,0.75);
    -moz-box-shadow: 10px 10px 89px -12px rgba(0,0,0,0.75);
    box-shadow: 10px 10px 89px -12px rgba(0,0,0,0.75);
}

.login-form h1 {
    text-align: center;
    margin-bottom: 25px;
}

.txtb {
    border-bottom: 2px solid #adadad;
    position: relative;
    margin: 30px 0;
}

.txtb input {
    font-size: 15px !important;
    color: #333;
    border: none;
    width: 100%;
    outline: none;
    background: none;
    padding: 0 5px;
    height: 40px;
}

.txtb span::before {
    content: attr(data-placeholder);
    position: absolute;
    top: 50%;
    left: 5px;
    color: #adadad;
    transform: translateY(-50%);
    z-index: -1;
    transition: .5s;
}

.txtb span::after {
    content: '';
    position: absolute;
    width: 0%;
    height: 2px;
    top: 100%;
    left:0;
    background: linear-gradient(120deg, #e4e5c2, #00402e);
    transition: .5s;
}

.focus + span::before {
    top: -5px;
}
.focus + span::after {
    width: 100%;
}

.logbtn {
    display: block;
    width: 100%;
    height: 50px;
    border: none;
    background: linear-gradient(120deg, #00703c, #00402e);
    background-size: 200%;
    color: #FFF;
    font-size: 20px;
    font-weight: bold;
    outline:none;
    cursor: pointer;
    transition: .5s;
}

.logbtn:hover {
    background-position: right;
}

@media screen and (max-width: 992px) {
  body {
    background-color: blue;
  }
}