:root {
    --background-color: rgb(255, 255, 255);
    --nav-background-color: rgb(196, 196, 196);
    --text-color: rgb(0, 0, 0);
    --text-color-hover: rgb(40, 134, 197);
    --arrow-menu-color: rgb(103, 106, 116);
}

header {
    grid-area: header
}

nav {
    grid-area: nav;
}

main {
    grid-area: main;
}

footer {
    grid-area: footer;
}

body {
    display: grid;
    grid-template-columns: 600px 1fr auto;
    grid-template-rows: auto auto;
    grid-template-areas:
        "header nav nav"
        "main main main"
        "footer footer footer";
    margin: 0;
    color: var(--text-color);
    background-color: var(--background-color);
}

header {
    background-color: var(--nav-background-color);
    width: 600px;
    padding: 5px 5px 5px 20px;
    display: flex;
    align-items: center;

    a {
        color: black;
    }
}

nav {
    display: flex;
    background-color: var(--nav-background-color);
    height: 100px;
    align-items: center;
    justify-content: flex-start;
    padding-left: 50px;
}

#nav_menu {
    column-gap: 30px;
}

nav a {
    text-decoration: none;
    color: rgb(0, 0, 0);
    font-size: 18px;
}

nav a:hover {
    color: var(--text-color-hover);
}

main {
    margin-top: 40px;
    justify-self: center;
    width: 700px;
}

main p {
    font-size: 16px;
}

a {
    text-decoration: none;
    color: rgb(0, 86, 245)
}

li a {
    color: blue;
    text-decoration: underline;
}

ul {
    display: flex;
    flex-direction: column;
    gap: 20px;
    font-size: 18px;
}

#current_tab {
    text-decoration: underline;
    color: blue;
}

footer {
    height: 100px;
    margin-top: 100px;
    background-color: black;
    display: flex;
    align-items: center;
    justify-content: flex-start;
    padding-left: 20px;
    color: white;
}

.bold {
    font-weight: bold;
}

#arrow_menu {
    display: none;
    font-size: 30px;
    user-select: none;
    margin-left: 10px;
}

.blue_underline {
    text-decoration: underline;
    color: blue;
}

.flex {
    display: flex !important;
}

@media (min-width: 1000px) {
    #nav_menu {
        display: flex;
    }
}

@media (max-width: 1200px) {
    body {
        grid-template-columns: 400px 1fr;
    }

    header {
        width: 400px;
        font-size: 12px;
    }
}

@media (max-width: 1000px) {
    #nav_menu {
        top: 180px;
        grid-template-columns: auto;
        display: none;
        z-index: 1;
        flex-direction: column;
        position: absolute;
        left: 0;
        width: 100%;
        background-color: var(--arrow-menu-color);
    }

    #nav_menu a {
        width: 100%;
        padding: 5px 0 5px 5px;
        border-top: 1px solid gray;
    }

    header {
        width: auto;
        justify-content: center;
        height: 80px;
    }

    nav {
        background-color: var(--arrow-menu-color);
        width: 100%;
    }

    body {
        grid-template-columns: 1fr;
        grid-template-rows: auto auto 1fr auto;
        grid-template-areas:
            "header"
            "nav"
            "main"
            "footer";
    }

    #arrow_menu {
        display: flex;
        cursor: pointer;
    }

    #nav_menu a:first-child {
        border-top: none;
    }
}

@media (max-width: 800px) {
    main {
        width: 90%;
    }

    main h3 {
        font-size: 30px;
    }

    main h2 {
        font-size: 30px;
    }

    main p {
        font-size: 20px;
    }
}