style.css

.quadrado{
    background: #C9D6FF;  /* fallback for old browsers */
    background: -webkit-linear-gradient(to right, #E2E2E2, #C9D6FF);  /* Chrome 10-25, Safari 5.1-6 */
    background: linear-gradient(to right, #E2E2E2, #C9D6FF); /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%,-50%);
    padding: 80px;
    border-radius: 15px;
    color: #000000;
    border:5px solid #fff;
}

* {
    margin: 0;
    padding: 0;
}

#titulo {
    font-family: sans-serif;
    color: #380B61;
} 



#check{
    display: inline-block;
}


fieldset {
    border: 0;
}


body{
    background: #74ebd5;  /* fallback for old browsers */
background: -webkit-linear-gradient(to right, #ACB6E5, #74ebd5);  /* Chrome 10-25, Safari 5.1-6 */
background: linear-gradient(to right, #ACB6E5, #74ebd5); /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */
    font-family: sans-serif;
    font-size: 1em;
    color: #59429d;
    margin-left: 36%;
    margin-top: 2%;
    justify-content: center;
}

input, select, textarea, button {
    font-family: sans-serif;
    font-size: 1em;
    color: #59429d;
    border-radius: 5px;
}

.grupo:before, .grupo:after {
    display: table;
}

.grupo:after {
    clear: both;
}


.campo {
    margin-bottom: 1em;
}

.campo label {
    margin-bottom: 0.2em;
    color: #59429d;
    display: block;
}


fieldset.grupo .campo {
    float:  left;
    margin-right: 1em;
}


.campo input[type="text"], .campo input[type="email"], .campo select, .campo textarea {
    padding: 0.2em;
    border: 1px solid #59429d;
    box-shadow: 2px 2px 2px rgba(0,0,0,0.2);
    display: block;
}


.campo select option {
    padding-right: 1em;
}

.campo input:focus, .campo select:focus, .campo textarea:focus {
    background: #E0E0F8;
}


.botao {
    font-size: 1.2em;
    background: #59429d;
    border: 0;
    margin-bottom: 1em;
    color: #ffffff;
    padding: 0.2em 0.6em;
    box-shadow: 2px 2px 2px rgba(0,0,0,0.2);
    text-shadow: 1px 1px 1px rgba(0,0,0,0.5);
    position: absolute;
    top: 90%;
    left: 50%;
    margin-right: -50%;
    transform: translate(-50%, -50%)
}


.botao:hover {
    background: #CCBBFF;
    box-shadow: inset 2px 2px 2px rgba(0,0,0,0.2);
    text-shadow: none;
}


.botao, select{
    cursor: pointer;
}