body {
    max-width: 1800px;
    margin: auto;
    padding: 20px;
    font-family: Arial, Helvetica, sans-serif;
    line-height: 1.7;
    color: #333;
    background: #fafafa;
}

h1 {
    color: #183153;
    border-bottom: 3px solid #d4a017;
    padding-bottom: 10px;
}

h2 {
    color: #183153;
    margin-top: 40px;
}

h3 {
    color: #2b5278;
    margin-top: 30px;
}

p {
    margin-bottom: 15px;
}

ul,
ol {
    margin-bottom: 20px;
}

li {
    margin-bottom: 8px;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin: 25px 0;
}

th {
    background: #183153;
    color: white;
}

th,
td {
    border: 1px solid #ccc;
    padding: 12px;
    vertical-align: top;
}

.index-subsection {
    display: block;
    margin-top: 4px;
    padding-top: 10px;
    border-top: 1px solid #ccc;
}

.index-subsubsection {
    display: block;
    margin-top: 8px;
    margin-left: 0.75em;
    color: #2b5278;
    font-size: 0.95em;
}

.index-document {
    display: block;
    margin-left: 1.5em;
    color: #333;
    font-size: 0.9em;
    font-weight: normal;
}

.index-topic {
    display: block;
    margin-left: 2.75em;
    color: #333;
    font-size: 0.88em;
    font-weight: normal;
}

a {
    text-decoration: none;
    color: #183153;
    font-weight: bold;
}

a:hover {
    text-decoration: underline;
}

.flashcards-link a {
    display: inline-block;
    border: 2px solid #183153;
    border-radius: 6px;
    padding: 10px 18px;
    color: white;
    background: #183153;
    text-decoration: none;
}

.flashcards-link a:hover,
.flashcards-link a:focus {
    border-color: #d4a017;
    background: #2b5278;
    text-decoration: none;
}

.summary-image {
    width: 100%;
    max-width: 1200px;
    display: block;
    margin: auto;
}

figure {
    text-align: center;
    margin: 30px 0;
}

figcaption {
    margin-top: 10px;
    font-style: italic;
    color: #666;
}

hr {
    margin: 30px 0;
}

/* Reusable content boxes */

.formula {
    background: #eef5ff;
    border-left: 6px solid #183153;
    padding: 20px;
    margin: 30px 0;
    font-size: 1.3em;
    font-weight: bold;
}

.note {
    background: #fff8e6;
    border-left: 5px solid #d4a017;
    padding: 18px;
    margin: 25px 0;
}

.exam {
    background: #eef9ee;
    border-left: 5px solid #2e7d32;
    padding: 20px;
    margin-top: 40px;
}

/* Progress colours */

.complete {
    background-color: #d4edda;
}

.inprogress {
    background-color: #fff3cd;
}

.planned {
    background-color: #f8d7da;
}