style.css

@import url('https://fonts.googleapis.com/css2?family=Ubuntu&display=swap');

*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Ubuntu', sans-serif;
}
body{
    width: 100%;
    height: 100vh;
    max-width: 100%;
    background: linear-gradient(to right, #5afaba 0%,  #2eea9f 0%, #178ca3 100%);
    display: grid;
    align-items: center;
    justify-content: center;
    margin: 0;
    position: relative;
}

.container form{
    max-width: 100%;
    padding: 50px 30px 20px;
    background: #fff;
    border-radius: 4px;
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.5);
    position: relative;
}
.fa-paper-plane{
    position: absolute;
    top: 0;
    left: 50%;
    color: #2eb0ec;
    transform: translate(-50%,-50%);
    background: #fff;
    font-size: 30px;
    padding: 20px;
    border-radius: 50%;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.5);
}
.container .headings{
    max-width: 100%;
    padding-bottom: 7%;
    padding-top: 15%;
}

.text-center{
    position: relative;
    text-align: center;
    padding-bottom: 2%;
    font-size: 45px;
}

p{
    position: relative;
    text-align: center;
    font-size: 25px;
}

.input-group{
    width: 100%;
    display: flex;
    align-items: center;
    margin: 10px 0;
    position: relative;
}
.input-group label{
    flex-basis: 28%;
}
.input-group input, .input-group textarea{
    flex-basis: 68%;
    background: transparent;
    border: 0;
    outline: 0;
    padding: 10px 0;
    border-bottom: 1px solid #999;
    color: #333;
    font-size: 16px;
}
::placeholder{
    font-size: 14px;
}

form .btn{
    background: linear-gradient(to right, #5afaba 0%,  #2eea9f 0%, #178ca3 100%);
    color: #000;
    border-radius: 4px;
    border: 1px solid #178ca3;
    padding: 10px 40px;
    outline: 0;
    cursor: pointer;
    display: block;
    margin: 30px auto 10px;
    font-size: 17px;
    font-weight: bold;
}

.input-group span{
    position: absolute;
    bottom: 12px;
    right: 17px;
    font-size: 14px;
    color: red;
}
.submit-group{
    color: red;
}

.input-group span i{
    color: rgb(25, 184, 94);
}