html
{
    margin: 0px;
    font-family: arial;
    transition-duration: 1s;
    transition-property: all;
    max-height: 100vh;
    background-image: linear-gradient(to bottom, #000000, #333A3B);
    color: #CFCFCF;
}
.body
{
    margin: 0px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    flex-wrap: wrap;
    transition-property:all;
    transition-duration: 1s;
    min-height: 100vh;
    text-align: center;
    justify-content:center;
    align-items:center;
}
.header
{   
    display: flex;
    flex-direction: row;
    text-align: center;
    justify-content:space-between;
    align-items: center;
    min-width: 100vw;
}
.nav_icon_header
{
    
}
.h2
{
}
.article_opisanie
{
}
.nav_button
{
}
}
.button_to_app_store
{
}
.button_to_app_store {
    width: 190px;
    height: 50px;
    border: none;
    outline: none;
    color: #fff;
    background: #111;
    cursor: pointer;
    position: relative;
    z-index: 0;
    border-radius: 10px;
}

.button_to_app_store:before {
    content: '';
    background: linear-gradient(45deg, #ff0000, #ff7f00, #ffff00, #00ff00, #00ffff, #002bff, #7a00ff, #fb00f3, #ff0000);
    position: absolute;
    top: -2px;
    left:-2px;
    background-size: 400%;
    z-index: -1;
    filter: blur(5px);
    width: calc(100% + 4px);
    height: calc(100% + 4px);
    animation: glowing 20s linear infinite;
    opacity: 1;
    transition: opacity .3s ease-in-out;
    border-radius: 10px;
}

.button_to_app_store:active {
    color: #000
}

.button_to_app_store:active:after {
    background: transparent;
}

.button_to_app_store:hover:before {
    animation: glowing 50s linear infinite;
}

.button_to_app_store:after {
    z-index: -1;
    content: '';
    position: absolute;
    width: 100%;
    height: 100%;
    background: #111;
    left: 0;
    top: 0;
    border-radius: 10px;
}

@keyframes glowing {
    0% { background-position: 0 0; }
    50% { background-position: 400% 0; }
    100% { background-position: 0 0; }
}
.app_icon
{
    max-height: 7vh;
    position: absolute;
    top: 3vh;
    left: 3vw;
}
@media (max-aspect-ratio: 1/1)
{
        .button_to_app_store {
        width: 390px;
        height: 100px;
        font-size: 1.7em;
    }
}