.browser-warning {
    width: calc(100% - 40px);
    margin: 1em auto;
    border: 3px solid orangered;
    padding: 1em;
    position: fixed;
    z-index: 9999;
    font-weight: bold;
    background: #fff;
    left: 0;
    right: 0;
    top: 2em;
    margin-left: auto;
    margin-right: auto;
}

.browser-warning button {
        position: absolute;
        top: 5px;
        right: 5px;
        width: 20px;
        height: 20px;
        padding: 0;
        border: 0;
        background: transparent;
}

.browser-warning p {
        font-weight: bold;
        margin: 0;
}

.browser-warning p:first-child {
    color: orangered;
}