#ex1 {
    font-family: sans-serif;
    margin: 0;

    header {
        background: purple;
        height: 100px;
    }

    h1 {
        text-align: center;
        color: white;
        line-height: 100px;
        margin: 0;
    }

    section {
        zoom: 0.8;
    }

    article {
        padding: 10px;
        margin: 10px;
        background: aqua;
    }
}

#ex2 {
    font-family: sans-serif;
    margin: 0;

    header {
        background: purple;
        height: 100px;
    }

    h1 {
        text-align: center;
        color: white;
        line-height: 100px;
        margin: 0;
    }

    section {
        zoom: 0.8;
        display: flex;
    }

    article {
        padding: 10px;
        margin: 10px;
        background: aqua;
    }
}

#ex3 {
    font-family: sans-serif;
    margin: 0;

    header {
        background: purple;
        height: 100px;
    }

    h1 {
        text-align: center;
        color: white;
        line-height: 100px;
        margin: 0;
    }

    section {
        zoom: 0.8;
        display: flex;
        flex-direction: column-reverse;
    }

    article {
        padding: 10px;
        margin: 10px;
        background: aqua;
    }
}

#ex4 {
    font-family: sans-serif;
    margin: 0;

    header {
        background: purple;
        height: 100px;
    }

    h1 {
        text-align: center;
        color: white;
        line-height: 100px;
        margin: 0;
    }

    section {
        /* overflow: scroll; */
        zoom: 0.8;
        display: flex;
        flex-direction: row;
    }

    article {
        padding: 10px;
        margin: 10px;
        background: aqua;
        min-width: 400px;
    }
}

#ex5 {
    font-family: sans-serif;
    margin: 0;

    header {
        background: purple;
        height: 100px;
    }

    h1 {
        text-align: center;
        color: white;
        line-height: 100px;
        margin: 0;
    }

    section {
        /* overflow: scroll; */
        flex-wrap: wrap;
        zoom: 0.8;
        display: flex;
        flex-direction: row;
    }

    article {
        padding: 10px;
        margin: 10px;
        background: aqua;
        min-width: 400px;
    }
}

#ex6 {
    font-family: sans-serif;
    margin: 0;

    header {
        background: purple;
        height: 100px;
    }

    h1 {
        text-align: center;
        color: white;
        line-height: 100px;
        margin: 0;
    }

    section {
        zoom: 0.8;
        display: flex;
    }

    article {
        flex: 1;
        padding: 10px;
        margin: 10px;
        background: aqua;
    }

    article:nth-of-type(3) {
        flex: 2;
    }
}

#ex7 {
    font-family: sans-serif;
    margin: 0;

    header {
        background: purple;
        height: 100px;
    }

    h1 {
        text-align: center;
        color: white;
        line-height: 100px;
        margin: 0;
    }

    section {
        zoom: 0.8;
        display: flex;
    }

    article {
        flex: 1 100px;
        padding: 10px;
        margin: 10px;
        background: aqua;
    }

    article:nth-of-type(3) {
        flex: 2 100px;
    }
}

#ex8 {
    font-family: sans-serif;
    width: 90%;
    max-width: 960px;
    margin: 10px auto;

    div {
        height: 100px;
        border: 1px solid black;
        display: flex;
        align-items: center;
        justify-content: space-around;
    }

    button {
        font-size: 18px;
        line-height: 1.5;
        width: 15%;
    }

    /* button:first-child {
        align-self: flex-end;
    } */
}

#ex9 {
    font-family: sans-serif;
    width: 90%;
    max-width: 960px;
    margin: 10px auto;

    div {
        height: 100px;
        border: 1px solid black;
        display: flex;
        align-items: center;
        justify-content: space-around;
    }

    button {
        font-size: 18px;
        line-height: 1.5;
        width: 15%;
    }

    button:first-child {
        order: 1;
    }

    button:last-child {
        order: -1;
    }
}

#ex10 {
    font-family: sans-serif;
    margin: 0;

    header {
        background: purple;
        height: 100px;
    }

    h1 {
        text-align: center;
        color: white;
        line-height: 100px;
        margin: 0;
    }

    section {
        zoom: 0.8;
        display: flex;
    }

    article {
        flex: 1 100px;
        padding: 10px;
        margin: 10px;
        background: aqua;
    }

    article:nth-of-type(3) {
        flex: 3 100px;
        display: flex;
        flex-flow: column;
    }

    article:nth-of-type(3) div:first-child {
        flex: 1 100px;
        display: flex;
        flex-flow: row wrap;
        align-items: center;
        justify-content: space-around;
    }

    button {
        flex: 1 auto;
        margin: 5px;
        font-size: 18px;
        line-height: 1.5;
    }
}