body {
    background: #003366;
    color: #cccccc;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
             Oxygen, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
    font-size: 1.4em;
    margin: clamp(10px, 3vw, 30px);
    margin-top: clamp(10px, 5vw, 40px);
}

a {
    font-weight: 700;
    color: #00FFFF;
    text-decoration: none;
}

strong {
    color: #f4f4f4;
    /* color: #ffd700;*/
    font-weight: 700;
}

#logo {
    margin-left: calc(50% - 150px);
    transition: 0.2s ease;
}

#logo img {
    width: 300px;
}

#page-header {
    margin-bottom: 80px;
    left: 50%;
    margin-left: calc(50% - 40vw);
    max-width: 80vw;
}

#page-header h1 {
    text-align: center;
    font-size: 2.2em;
    margin-top: 10px;
    margin-bottom: 20px;
    color: #ffffff;
}

#page-header h3 {
    text-align: center;
    font-size: 1.1em;
    color: #ffffff;
}

#page-header p {
    text-align: center;
}

/* Sticky nav bar */
.navbar {
    position: sticky;
    background: #003366;
    top: 0;
    iborder-top: 1px solid #ccc;
    border-bottom: 1px solid #00ffff;
    z-index: 1000;
    text-align: center;
    font-weight: bold;
    height: 0.6em;
    padding-top: 30px;
    margin-top: 1em;
    margin-bottom: 2em;
    margin-left: 4.8vw;
    margin-right: 4vw;
}

/* Nav links look like part of the rule */
.navbar a {
    position: relative;
    top: 0px;
    text-decoration: none;
    background: #003366;
    color: #00ffff;
    margin: 0 1em;
    padding: 0.25em 0.5em;
    border: 1px solid #00FFFF;
    border-radius: 8px;
    transition: background 0.2s ease;
}

.navbar a:hover {
    color: #003366;
    background: #00ffff;
}

.navbar .logo-small {
    position: absolute;
    z-index: 1100;
    top: 0px;
    left: 0px;
    width: 100px;
    opacity: 0;
    margin-top: -10px;
    margin-left: -10vw;
    transition: opacity 0.2s ease;
    pointer-events: none;
}

.sticky-trigger {
    height: 1px;
}

#stucklogo {
    position: sticky;
    top: 5px;
    left: 10px;
    z-index: 1100;
    margin-left: -3vw;
    opacity: 0;
    transition: opacity 0.2s ease;
    height: 0px;
}

/* Show the logo when scrolled past the trigger */
body.stuck #stucklogo {
    opacity: 1;
    height: 80px;
}

.content {
    margin: 0 auto;
    width: 85vw;
    padding: 1rem;
    max-width: 1000px;
    box-sizing: border-box;

}

.content h2 {
    margin-left: -1rem;
    padding-top: 3rem;
    color: #ffffff;
} 

.content h3 {
    margin-left: -1rem;
    color: #ffffff;
} 

.expander input[type="checkbox"] {
    display: none;
}

.expander label {
    display: inline-block;
    cursor: pointer;
    font-weight: 700;
    font-size: 1.2em;
    left: 20%;
    transform: translateX(-30%);
    color: #ffffff;
    margin-bottom: 0.5rem;
    position: relative;
    padding-right: 0.5em;
    padding-left: 1.5em;
    margin-bottom: 1em;
    width: 80%;
    max-width: 30rem;
    text-decoration: underline;
    iborder-bottom: 1px solid white;
}


.expander label::after {
    icontent: "▶"; 
    content: "▼";
    position: absolute;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    transform-origin: center center; 
    transition: transform 0.2s ease;
}

/* Rotate caret when open */
.expander input[type="checkbox"]:checked + label::after {
    transform: translateY(-30%) rotate(180deg); /* downward arrow */
}

.expander .body {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
    padding-left: 5vw;
}

.expander input[type="checkbox"]:checked ~ .body {
    max-height: 200vh; 
    margin-bottom: 2em;
}

.mono {
    font-family: monospace;
}

.checkmark {
    color: #00aaaa;
}

.checkmark::before {
    content: "✔";
    color: #00aaaa;
    position: absolute;
    display: inline-block;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    font-family: "Arial", sans-serif; 
}

hr {
    margin-top: 2rem;
    max-width: 60vw;
    color: #00AAAA;
}

.tooltip-container {
    position: relative;
    display: inline-block;
    cursor: help;
}

.tooltip-container .tip {
    visibility: hidden;
    opacity: 0;
    background-color: #000033;
    color: #00FFFF;
    text-align: center;
    border-radius: 8px;
    padding: 0.5em;
    position: absolute;
    z-index: 10;
    bottom: 125%;  /* position above the element */
    left: 50%;
    transform: translateX(-20%);
    max-width: 80vw;

    transition: opacity 0.2s ease;
    pointer-events: none; /* don't interfere with mouse events */
}

.tooltip-container:hover .tip {
    visibility: visible;
    opacity: 1;
}

.tooltip {
    position: relative;
    cursor: help;
}

.tooltip::after {
    content: attr(data-tip);
    position: absolute;
    bottom: 125%;
    left: 50%;
    transform: translateX(-20%);
    background: #000033;
    color: #00FFFF;
    padding: 0.4em 0.6em;
    border-radius: 8px;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease;
    z-index: 10;
    visibility: hidden;
}

.tooltip:hover::after {
    opacity: 1;
    visibility: visible;
}

@media (max-width: 768px) {
    .checkmark::before {
        content: "✅";
    }
    .navbar {
        font-size: 1em;
        border: none;
        margin-top: 10px;
        margin-bottom: 10px;
        padding: 0px;
    }
    .navbar a {
        height: 1.2em;
        border: none;
        margin: 1em;
    }
    .tooltip::after {
        position: static;
        display: inline;
        content: " (" attr(data-tip) ")";
        background: none;
        max-width: 80vw;
        color: #00AAAA;
        padding: 0;
        opacity: 1;
        visibility: visible;
        font-weight: normal;
        transform: none;
        white-space: normal;
        word-break: break-word;
        overflow-wrap: break-word;
    }

    .tooltip:hover::after {
    }
}