.tabs {
    /*font-size: 0;*/
    margin-left: auto;
    margin-right: auto;
    margin-bottom: 1rem;
}
    .tabs form {
        padding: 1em;
    }
    .tabs > input[type="radio"] {
        display: none;
    }

    .tabs > div {
        /* скрыть контент по умолчанию */
        display: none;
        /*border: 1px solid #e0e0e0;
        padding: 10px 15px;*/
        /*font-size: 16px;*/
    }

/* отобразить контент, связанный с вабранной радиокнопкой (input type="radio") */
#tab-btn-1:checked ~ #content-1,
#tab-btn-2:checked ~ #content-2,
#tab-btn-3:checked ~ #content-3 {
    display: block;
}

.tabs > label {
    display: inline-block;
    text-align: center;
    vertical-align: middle;
    user-select: none;
    background-color: #ef402f;
    color: white;
    border: 1px solid #e0e0e0;
    padding: 2px 15px;
    /*font-size: 16px;*/
    line-height: 2;
    transition: color 0.15s ease-in-out, background-color 0.15s ease-in-out;
    cursor: pointer;
    position: relative;
    top: 1px;
    margin-bottom: 0;
    border-radius: 7px 7px 0 0;
}

    .tabs > label:not(:first-of-type) {
        margin-left: 5px;
    }

.tabs > input[type="radio"]:checked + label {
    background-color: #fff;
    color: #5a666e;
    border-bottom: 1px solid #fff;
}

.tabs > .tabs-underline {
    display: block;
    border-bottom: 1px solid #e0e0e0;
}

.tabs > input[type="radio"]:not(:checked) + label:hover {
    color: #fff;
    background-color: #c82333;
    border-color: #bd2130;
}