.tabs-navigation button {
        padding: 10px 15px;
        border: 1px solid #ddd;
        border-bottom: none;
        background-color: #f0f0f0;
        cursor: pointer;
        outline: none;
    }
    .tabs-navigation button.active-tab {
        background-color: #fff;
        border-bottom: 1px solid #fff;
        font-weight: bold;
    }
    .error {
        color: red;
        font-size: 0.9em;
        margin-top: 5px;
    }