.tekstbox {
    height: 45px;
    border: none;
    border-bottom: 1px solid #ccc;
    padding-left: 0;
    padding-right: 0;
    border-radius: 0;
    background: red;
    display: block;
    width: 100%;
    height: calc(1.5em + 0.75rem + 2px);
    padding: 0.375rem 0.75rem;
    font-size: 1rem;
    font-weight: 400;
    line-height: 1.5;
    color: #495057;
    background-color: #fff;
    background-clip: padding-box;
    border: 1px solid #ced4da;
    border-radius: 0.25rem;
    -webkit-transition: border-color 0.15s ease-in-out, -webkit-box-shadow 0.15s ease-in-out;
    transition: border-color 0.15s ease-in-out, -webkit-box-shadow 0.15s ease-in-out;
    -o-transition: border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
    transition: border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
    transition: border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out, -webkit-box-shadow 0.15s ease-in-out
}

    .tekstbox:active, .tekstbox:focus {
        outline: none;
        -webkit-box-shadow: none;
        box-shadow: none;
        border-color: #000;
    }