@media (min-width:320px)  { /* smartphones, portrait iPhone, portrait 480x320 phones (Android) */ }
@media (min-width:480px)  { /* smartphones, Android phones, landscape iPhone */ }
@media (min-width:600px)  { /* portrait tablets, portrait iPad, e-readers (Nook/Kindle), landscape 800x480 phones (Android) */ }
@media (min-width:801px)  {
    .v1-block, .v2-block {
        padding: 25px;
        display: flex;
        align-items: flex-end;
        max-width: 570px;
        padding: 25px;
        display: flex;
        align-items: flex-end;
        width: 48%;
    }
    .v1-block img, .v2-block img {
        height: 95%;
        margin-bottom: 0;
        margin-right: 30px;
    }
    .brand-section, .model-wrapper {
        gap: 20px;
    }
}
@media (min-width:1025px) { /* big landscape tablets, laptops, and desktops */ }
@media (min-width:990px) {
    section.main-section {
        justify-content: space-between;
        flex-direction: row;
    }
    .course-block, .po-block {
        width: auto;
        height: 63.5%;
    }
    .navigation {
        display: block;
    }
    .user-menu ul li:not(:nth-child(2)) {
        display: block;
    }
    .course-block h2, .po-block h2 {
        top: 32px;
    }
    .mobile-nav {
        display: none;
    }
}