Tamanho do input com "box-sizing: border-box;"

by Salustiano Silva

HTML

<input type="text" class="old" value="Bubu está escondido">
<br>    
<input type="text" class="new" value="Bubu está aqui!">

CSS

input.old {
    width: 100%;
    height: 35px;
    margin-bottom: 10px;
    color: #595959;
    padding-top: 17px;
    padding-right: 17px;
    padding-bottom: 17px;
    padding-left: 35px !important;
    box-sizing: border-box;
    background: none repeat scroll 0% 0% #FFF;
    border-radius: 5px;
    overflow: auto;
    outline: 0px none;
    border: 2px solid blue;
    font-size: 15px;
    transition: border 0.5s ease 0s;
    opacity: 1;
}
input.new {
    width: 100%;
    height: 38px;
    margin-bottom: 10px;
    color: #595959;
    padding-right: 17px;
    padding-left: 35px !important;
    box-sizing: border-box;
    background: none repeat scroll 0% 0% #FFF;
    border-radius: 5px;
    overflow: auto;
    outline: 0px none;
    border: 2px solid blue;
    font-size: 15px;
    transition: border 0.5s ease 0s;
    opacity: 1;
}