.start_btn, .start_btn1 {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2),
        0 6px 20px 0 rgba(0, 0, 0, 0.19);
}

.start_btn, .start_btn1 {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2),
        0 6px 20px 0 rgba(0, 0, 0, 0.19);
}

.start_btn button,
.start_btn1 button {
    font-size: 25px;
    font-weight: 500;
    color: #007bff;
    padding: 15px 30px;
    outline: none;
    border: none;
    border-radius: 5px;
    background: #fff;
    cursor: pointer;
}


@media only screen and (max-width: 600px) {
    ::selection {
        color: #fff;
        background: #007bff;
    }

    .start_btn,
    .info_box,
    .quiz_box,
    .result_box {
        position: absolute;
        top: 50%;
        left: 50%;
        transform: translate(-50%, -50%);
        box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2),
            0 6px 20px 0 rgba(0, 0, 0, 0.19);
    }

    .start_btn button {
        font-size: 25px;
        font-weight: 500;
        color: #007bff;
        padding: 15px 30px;
        outline: none;
        border: none;
        border-radius: 5px;
        background: #fff;
        cursor: pointer;
    }
}