* {
    box-sizing: border-box;
}

body {
    display: flex;
    flex-direction: column;
    background-color: aqua;
    margin: 0;
    padding: 0;
}

header {
    background-image: radial-gradient(red, yellow, green);
    display: flex;
    flex-direction: column;
    justify-content: space-around;
    align-items: center;
}

main {
    display: flex;
    flex-direction: column;
    background-color: green;
    height: 50%;
}

footer {
    background-color: gainsboro;
    padding: 0.5em;
    font-size: 25px;
}

p {
    text-indent: 40px;
}

h2 {
    text-align: center;
}

.stack {
    margin-top: 16px;
    font-size: 13px;
    color: #666;
    padding-top: 12px;
    border-top: 1px solid #eee;
}

.center {
    text-align: center;
}

.right {
    text-align: right;
}

.left {
    text-align: left;
}

article {
    padding: 0.5em;
    font-size: 25px;
}

.button {
    border-radius: 15px;
    background-color: chocolate;
    font-size: 20px;
    color: black;
    font-weight: bold;
}

.pris {
    font-family: 'Lobster', cursive;
    color: darkred;
}


/* для телефонов */

@media only screen and (max-width: 480px) {
    footer a {
        display: block;
    }
}


/* для планшетов */

@media (min-width: 481px) and (max-width:768px) {
    article {
        padding: 0.5em;
        font-size: 22px;
    }
}


/* For desktop and tablets: */

@media only screen and (min-width: 769px) {
    header {
        display: flex;
        flex-direction: row;
    }
    body {
        min-height: 100vh;
    }
    main {
        display: flex;
        flex-direction: row;
        min-height: 100%;
        flex: 1 1 auto;
    }
    article {
        padding: 0.5em;
        font-size: 18px;
    }
    footer {
        font-size: 18px;
    }
    .col-1 {
        width: 8.33%;
    }
    .col-2 {
        width: 16.66%;
    }
    .col-3 {
        width: 25%;
    }
    .col-4 {
        width: 33.33%;
    }
    .col-5 {
        width: 41.66%;
    }
    .col-6 {
        width: 50%;
    }
    .col-7 {
        width: 58.33%;
    }
    .col-8 {
        width: 66.66%;
    }
    .col-9 {
        width: 75%;
    }
    .col-10 {
        width: 83.33%;
    }
    .col-11 {
        width: 91.66%;
    }
    .col-12 {
        width: 100%;
    }
}