.ventana-anuncio {
    background: rgba(33, 41, 52, .85);
    left: 0;
    bottom: 0;
    right: 0;
    top: 0;
    display: flex;
    position: fixed;
    z-index: 999;
}
.ventana-anuncio .content {
    background: #ffffff;
    border-radius: 2px;
    box-shadow: 0 1px 3px rgba(33, 41, 52, .75);
    box-sizing: content-box;
    display: flex;
    flex-direction: column;
    margin: auto;
    max-width: 600px;
    min-width: 320px !important;
    overflow: hidden;
    position: relative;
    width: 100%;
    padding: 1%;
    font-size: 1.3rem;
}

.content-buttons{
    text-align: right;
}