produto2.css

/*____________________________*/
img {
    float: left;
}
/*____________________________*/
.cores label:after {
    content: '';
    display: block;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    position: absolute;
    top: 30px;
    border: 6px solid rgba(0,0,0,0);
    transition: 1s;
    -moz-box-sizing: border-box;
         box-sizing: border-box;
}
.cores label:hover:after {
    border: 6px solid rgba(0,0,0,0.1);
}
label[for=verde]:after {
    background-color: #33CC66;
    left: 0;
}
label[for=rosa]:after {
    background-color: #FF6666;
    left: 60px;
}
label[for=azul]:after {
    background-color: #6666FF;
    left: 120px;
}

.cores input:checked + label:after {
    border: 6px solid rgba(0,0,0,0.3);
}
.cores input[type=radio]{
    display: none;
}
.cores input:not(:checked) + label img {
    display: none;
}
.cores {
    position: relative;
    padding-top: 90px;
}

/* FiroFox */
@media (min--moz-device-pixel-ratio:0){
    .cores legend {
    position: absolute;
    top: 0;
    left: 0;
    }
    fieldset {
        display: table-column;
    }
}
/* FireFox */

.cores label img {
    display: block;
    max-width: 100%;
}

.produto {
    color: #333;
    line-height: 1.3;
    margin-top: 2em;
}

.produto h1 {
    font-size: 1.8em;
    font-weight: bold;
}

.produto p {
    font-size: 1.2em;
    font-style: italic;
    margin-bottom: 1em;
}

.produto legend {
    display: block;
    font: bold 0.9em/2.5 Arial;
    text-transform: uppercase;
}

.comprar {
    background: #91BD3C;
    border: none;
    color: #333;
    font-size: 1.4em;
    text-transform:uppercase;
    box-shadow: 0 1px 3px #777;
    display:block;
    padding: 0.5em 1em;
    margin: 1em 0;
}

@media (min-width: 600px){
    img {
        float:left;
    }
}

@media (min-width: 630px) {
    .produto {
        position:relative;
        padding-left: 40%;
    }
    .cores {
        position: static;
        padding: 0;
    }
    .cores legend {
        position: static;
    }
    .cores label img {
        position: absolute;
        top: 0;
        left: 0;
        max-height: 100%;
        max-width: 35%;
    }
    .cores label:after{
        position: static;
        float: left;
        margin-right: 10px;
    }
    .produto {
        font-size: 1.2em;
    }
}