secompletoestilos.css

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/*Estilos formulario*/

form{
    background: #089c7c;  /* fallback for old browsers */
    background: -webkit-linear-gradient(to top, #3cff87, #089c7c);  /* Chrome 10-25, Safari 5.1-6 */
    background: linear-gradient(to top, #3cff87, #089c7c); /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */   
    width: 100%;                       /*Cuerpo del formulario*/
    height: 625px;
    padding: 100px 150px 60px 150px;
    margin: auto;
    box-shadow: 2px 2px 6px 2px rgba(255, 255, 255, 0.8);
    overflow: hidden;
} 

.enviado h2{
    text-align: center;
    padding: 132px 0px 50px 0px;
    cursor: pointer;
}

.enviado i{
    margin: 8px;
}

/*Boton de regreso*/

.textosnoticiasextra .botonnotiextra{
    margin: 10px 100px 80px 370px;
}

.botonnotiextra{
    position: relative;
    display: block;
    height: 60px;
    width: 300px;
    border-radius: 10px;
    background: #089c7c; 
    font-size: 20px;
    overflow: hidden;
    transition: all .5s ease-in-out;
    border: 2px;
    cursor: pointer;
    margin: 0px 0px 100px 0px;
}

.botonnotiextra:hover{
    width: 350px;
    background: #000000;
    box-shadow: 0 0 10px #0000, 0 0 10px, #000000 0 0 10px;
}

.botonnotiextra i{
    padding: 5px;
}

.textosnoticiasextra a{
    text-decoration: none;
    color: #ffffff;
}


@media screen and (max-width:650px){
    form{
        height: 900px;
        padding: 100px 10px 50px 10px;
    } 

    .textosnoticiasextra .botonnotiextra{
        width: 250px;
        margin: 10px 10px 10px 30px;
    }

    .botonnotiextra:hover{
        width: 300px;
    }
}