/* Password Overlay */
#password-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.8);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

#password-form {
    background-color: white;
    padding: 1.25rem; /* 20px */
    border-radius: 0.3125rem; /* 5px */
    text-align: center;
}

#password-form h2 {
    margin-bottom: 1.25rem; /* 20px */
}

#password-form input[type="password"] {
    width: 100%;
    padding: 0.625rem; /* 10px */
    margin-bottom: 0.625rem; /* 10px */
}

#password-form input[type="submit"] {
    padding: 0.625rem 1.25rem; /* 10px 20px */
}

/* General Page Styles */
body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-size: 0.8rem; /* ~12.8px, 20% smaller than 16px */
}

header {
    background-color: #333;
    color: white;
    padding: 0.625rem 0; /* 10px 0 */
}

header nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    text-align: center;
}

header nav ul li {
    display: inline;
    margin: 0 0.625rem; /* 0 10px */
}

header nav ul li a {
    color: white;
    text-decoration: none;
}

main {
    padding: 1.25rem; /* 20px */
}

/* Topic Headers */
.topic-header {
    font-size: 1.2rem; /* was 1.5em, now 20% smaller */
    margin-top: 1.25rem; /* 20px */
    margin-bottom: 0.625rem; /* 10px */
    color: #333;
}

/* Book Summaries */
.book {
    margin-bottom: 1.25rem; /* 20px */
    padding: 0.9375rem; /* 15px */
    border: 1px solid #ddd;
    border-radius: 0.3125rem; /* 5px */
    background-color: #f9f9f9;
}

.book h2 {
    margin-top: 0;
}

.book h3 {
    margin: 0.3125rem 0; /* 5px 0 */
    font-weight: normal;
    color: #666;
}

.book p {
    margin: 0.625rem 0; /* 10px 0 */
    line-height: 1.5;
}

/* Knowledge Items */
.knowledge-item {
    margin-bottom: 1.25rem; /* 20px */
    padding: 0.9375rem; /* 15px */
    border: 1px solid #ddd;
    border-radius: 0.3125rem; /* 5px */
    background-color: #f9f9f9;
}

.knowledge-item h2 {
    margin-top: 0;
}

.knowledge-item p {
    margin: 0.625rem 0; /* 10px 0 */
    line-height: 1.5;
}