#table-of-contents {
    position: fixed;
    top: 50%;
    left: 20px;
    padding: 10px;
    font-size: 1em;
    font-family: 'Source Sans 3', sans-serif;
    line-height: 1.5;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease-in-out, visibility 0.3s;
    transform: translateY(-50%);
    display: flex;
    align-items: center;
    z-index: 100;
}

#toc-indicator {
    position: absolute;
    left: -10px;
    width: 3px;
    background-color: #1a1a1a;
    transition: top 0.2s ease-out, height 0.2s ease-out;
    border-radius: 2px;
}

#table-of-contents.visible {
    opacity: 1;
    visibility: visible;
}

#table-of-contents ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

#table-of-contents li {
    margin-bottom: 10px;
}

#table-of-contents a {
    text-decoration: none;
    color: #333;
}

#table-of-contents a.active {
    color: #1a1a1a;
    font-weight: bold;
}

#table-of-contents a.inactive {
    color: #999; /* Greyed out */
}


body {
    margin: 0;
    padding: 0;
    background-color: #f7f7f2;
    color: #333;
    font-family: 'Source Sans 3', sans-serif;
    line-height: 1.8;
}

.container {
    max-width: 680px;
    margin: 0 auto;
    padding: 40px 20px;
}

.hero {
    padding: 80px 20px;
    text-align: center;
}

h1 {
    font-size: 2.5em;
    margin-bottom: 20px;
    color: #1a1a1a;
}

.summary {
    font-size: 1.2em;
    max-width: 600px;
    margin: 0 auto;
    margin-bottom: 40px;
    text-align: center;
}

.content {
    margin: 60px auto;
}

h2 {
    color: #1a1a1a;
    margin-top: 40px;
    text-align: center;
}

p {
    text-align: justify;
    hyphens: auto;
    margin-bottom: 1.5em;
}

.contact-section {
    margin: 80px 0;
    padding: 40px 0;
    border-top: 1px solid #ddd;
    border-bottom: 1px solid #ddd;
    text-align: center;
}

.contact-section p {
    text-align: center;
    font-size: 1em;
    color: #333;
    margin-bottom: 20px;
}

.linkedin-icon {
    display: inline-block;
    margin-top: 10px;
}

.linkedin-icon img {
    width: 24px;
    height: 24px;
    vertical-align: middle;
}

footer {
    text-align: center;
    padding: 40px 20px;
    color: #666;
    font-size: 0.9em;
}

.principles {
    margin: 40px 0;
    padding-left: 0;
}

.principles li {
    list-style: none;
    margin-bottom: 1em;
    text-align: justify;
    padding-left: 1.5em;
    position: relative;
}

.principles li:before {
    content: "•";
    position: absolute;
    left: 0;
    color: #666;
}

.details-section {
    margin: 60px 0;
}

.details-section h3 {
    cursor: pointer;
    margin: 20px 0;
    font-size: 1.2em;
    color: #1a1a1a;
    display: flex;
    align-items: center;
}

.details-section h3::after {
    content: "\25BA";
    font-size: 0.8em;
    margin-left: 10px;
    transition: transform 0.2s;
}

.details-section h3.expanded::after {
    content: "\25BC";
    transform: rotate(0);
}

.details-section .content {
    max-height: 0;
    overflow: hidden;
    margin: 10px 0 20px;
    transition: max-height 0.1s ease-out;
}

.details-section .collapsible-header.expanded + .content {
    max-height: 500px; /* Adjust based on your content height */
}

@media (max-width: 720px) {
    .container {
        padding: 40px 30px;
    }

    p,
    .principles li {
        text-align: left;
    }

    #table-of-contents {
        position: fixed;
        bottom: 0;
        left: 0;
        right: 0;
        top: auto;
        transform: none;
        background: white;
        padding: 10px 20px;
        box-shadow: 0 -2px 5px rgba(0,0,0,0.1);
        display: flex;
        justify-content: center;
        align-items: center;
        height: 60px;
    }

    #table-of-contents ul {
        display: flex;
        gap: 20px;
        overflow-x: auto;
        white-space: nowrap;
    }

    #table-of-contents li {
        margin: 0;
    }

    #toc-indicator {
        display: none;
    }
}

.collapsible-header {
    cursor: pointer;
    margin: 20px 0;
    font-size: 1.2em;
    color: #1a1a1a;
    display: flex;
    align-items: center;
}

.collapsible-header::after {
    content: "\25BA"; /* Right arrow */
    font-size: 0.8em;
    margin-left: 10px;
    transition: transform 0.2s;
}

.collapsible-header.expanded::after {
    content: "\25BC"; /* Down arrow */
    transform: rotate(0);
}