input, button, select, optgroup, textarea {
    margin: 10px;
    margin: 4px;
    font-family: inherit;
    font-size: inherit;
    line-height: inherit;
    width: 100%;
    border-radius: 5px;
    padding: 10px;
}

.btn {
    width: 100px;
    background-color: royalblue;
}