/* Tokens */

:root {
    /* Brand Palette */
    --brand-charcoal: #231f20; /* MIT charcoal */
    --brand-quiet-blue: #6B88A6; /* your chosen quiet blue */
    --brand-white: #FFFFFF;
    /* Semantic Colors */
    --color-bg: var(--brand-white);
    --color-text: var(--brand-charcoal);
    --color-accent: var(--brand-quiet-blue);
    --color-alert-soft: #f5b7c4; /* soft salmon for accessibility */
    --color-border: rgba(0,0,0,0.1);
    /* Typography */
    --font-sans: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
    --font-mono: "JetBrains Mono", monospace;
    --font-size-base: 0.9375rem;
    --font-size-lg: 1.25rem;
    --font-size-xl: 1.5rem;
    --line-height-base: 1.6;
    /* Layout & Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 1rem;
    --space-4: 1.5rem;
    --space-5: 2rem;
    --space-6: 3rem;
    --space-7: 5rem;
    --max-width-content: 1200px; /*72rem; ~1150px – excellent for report-like reading */
}








/* Layout */

html {
    scrollbar-gutter: stable;
}


html, body {
    height: 100%;
    margin: 0;
    background-color: var(--color-bg);
}

body {
    display: flex;
    flex-direction: column;
    color: var(--color-text);
    font-family: var(--font-sans);
    font-size: var(--font-size-base);
    line-height: var(--line-height-base);
}

header{ 
    min-height: 3.5em;
}

main {
    flex: 1;
    margin-bottom: 2em;
}



.indent {
  /*  padding-left: 1em;*/
    padding-left: var(--space-3); /* 1rem */
}

footer {
    border-top: 1px solid var(--color-border);
    text-align: right;
    font-size: 0.875rem;
    color: rgba(35, 31, 32, 0.65);
}





h1 {
    margin-top: 1.4em;
    margin-bottom: 1rem;
    font-size: 1.7em;
    font-weight: 500;
    line-height: 1.2em;
}

h2, h3, h4, h5 {
    font-size: 1.1em;
    font-weight: 500;
    margin-top: var(--space-5);
    margin-bottom: var(--space-2);
    padding: 0;
    letter-spacing: 0.02em;
}

/*h2 {
    font-size: 1.25em;
    margin-top: var(--space-5);
    margin-bottom: var(--space-2);
}*/


.inner{
   /* max-width: 1200px;*/
    margin: auto; 
    padding-left: 1em;
    padding-right: 1em;
}

.sidebar-content {
    font-size: .9em;
    --padding-left: 1em;
    --padding-right: 1em;
}

p {
    margin-top: 0;
    margin-bottom: var(--space-3);
}

/* Layout primitives*/

.layout-column > :first-child {
    margin-top: 0;
}

.layout-2col {
    display: grid;
    grid-template-columns: 1fr;
    row-gap: 1.5rem;
}



.page-title {
    /*  grid-column: 1 / -1; */
    grid-column: 1;
}





#main-logo {
    width:225px;
    display:block;
}






a {
    color: var(--brand-charcoal);
    text-decoration: underline;
    text-decoration-color: rgba(35, 31, 32, 0.4);
    text-decoration-color: rgba(35, 31, 32, 0.33);
    text-underline-offset: 4px;
}
a:visited {
    color: var(--brand-charcoal);
}

a:hover {
    text-decoration: underline;
    color: black;
    }

/*.menu a{
    text-decoration: none;   
}

    .menu a:hover {
        text-decoration: underline;
        text-decoration-color: rgba(35, 31, 32, 0.5);
        text-decoration-thickness: 1px;
        }*/








/* Components */

.primary-menu {
    display: none;
    font-size: 1.25em;
}

    .primary-menu.is-open {
        display: block;
        position: absolute;
        top: 100%; /* directly below logo + hamburger row */
        left: 0;
        right: 0;
        background: #fff;
        box-shadow: 0 12px 28px rgba(0,0,0,0.08);
        padding: 0.75rem 0;
        z-index: 999;
        padding-bottom: 2em;
    }

    .primary-menu ul {
        text-decoration: none;
        list-style: none;
        margin: 0;
    }

    .primary-menu li {
        padding: 2rem .25rem 0 .25rem;
    }

    .primary-menu ul a {
        text-decoration: none;
    }


.menu-toggle {
    background: none;
    border: 0;
    padding: 0.25rem 0.5rem;
    margin-left: auto;
    font-size: 1.8rem;
    line-height: 1;
    cursor: pointer;
    color: #231f20; /* MIT charcoal */
}









@media (min-width: 1100px) {

    .inner {
        padding-left: 6em;
        padding-right: 6em;
    }

    #main-logo {
        width: 175px;
    }

    .mobile-display {
        display: none;
    }



    .primary-menu {
        display: block;
        font-size: inherit;
    }

        .primary-menu li {
            display: inline-block;
            margin-left: 3.5rem;
            padding: 0;
        }

            .primary-menu li a {
                text-decoration: none;
                width: 100%;
            }

                .primary-menu li a:hover {
                    text-decoration: underline;
                    text-decoration-color: rgba(35, 31, 32, 0.33);
                    text-decoration-color: black;
                    text-underline-offset: 5px;
                }







    h1 {
        font-size: 2.1em;
    }


    .layout-2col {
        grid-template-columns: minmax(0,1fr) 320px;
        column-gap: 8rem;
        row-gap: 1.5rem;
        align-items: start;
    }     
}