:root {
    --bg-color: #ffffff;
    --text-color: #333333;
    --accent-color: #0056b3;
    --border-color: #e0e0e0;
    --hover-color: #003d82;
    --theme-bg: #f5f5f5;
    --theme-border: #ddd;
    --theme-hover: #e0e0e0;
    --date-color: #555555;
    --bg-primary: #ffffff;
    --bg-secondary: #f5f5f5;
    --bg-tertiary: #eaeaea;
    --bg-hover: #f0f0f0;
    --text-primary: #333333;
    --button-bg: #f5f5f5;
    --button-hover-bg: #e0e0e0;
    --focus-outline-color: #0056b3;
    --progress-bg: #e0e0e0;
    --accent-hover: #003d82;
}

/* Dark theme variables when system prefers dark mode (auto setting) */
@media (prefers-color-scheme: dark) {
    :root {
        --bg-color: #1a1a1a;
        --text-color: #e0e0e0;
        --accent-color: #5fa9ff;
        --border-color: #404040;
        --hover-color: #8ac2ff;
        --theme-bg: #2d2d2d;
        --theme-border: #404040;
        --theme-hover: #3d3d3d;
        --date-color: #a0a0a0;
        --bg-primary: #1a1a1a;
        --bg-secondary: #2d2d2d;
        --bg-tertiary: #3d3d3d;
        --bg-hover: #333333;
        --text-primary: #e0e0e0;
        --button-bg: #2d2d2d;
        --button-hover-bg: #3d3d3d;
        --focus-outline-color: #5fa9ff;
        --progress-bg: #404040;
        --accent-hover: #8ac2ff;
    }
}

/* Light theme variables when manually selected */
html[data-theme='light'] {
    --bg-color: #ffffff;
    --text-color: #333333;
    --accent-color: #0056b3;
    --border-color: #e0e0e0;
    --hover-color: #003d82;
    --theme-bg: #f5f5f5;
    --theme-border: #ddd;
    --theme-hover: #e0e0e0;
    --date-color: #555555;
    --bg-primary: #ffffff;
    --bg-secondary: #f5f5f5;
    --bg-tertiary: #eaeaea;
    --bg-hover: #f0f0f0;
    --text-primary: #333333;
    --button-bg: #f5f5f5;
    --button-hover-bg: #e0e0e0;
    --focus-outline-color: #0056b3;
    --progress-bg: #e0e0e0;
    --accent-hover: #003d82;
}

/* Dark theme variables when manually selected */
html[data-theme='dark'] {
    --bg-color: #1a1a1a;
    --text-color: #e0e0e0;
    --accent-color: #5fa9ff;
    --border-color: #404040;
    --hover-color: #8ac2ff;
    --theme-bg: #2d2d2d;
    --theme-border: #404040;
    --theme-hover: #3d3d3d;
    --date-color: #a0a0a0;
    --bg-primary: #1a1a1a;
    --bg-secondary: #2d2d2d;
    --bg-tertiary: #3d3d3d;
    --bg-hover: #333333;
    --text-primary: #e0e0e0;
    --button-bg: #2d2d2d;
    --button-hover-bg: #3d3d3d;
    --focus-outline-color: #5fa9ff;
    --progress-bg: #404040;
    --accent-hover: #8ac2ff;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    margin: 0;
    padding: 20px;
    max-width: 800px;
    margin: 0 auto;
}

/* Container that can expand to full width */
.container-fluid {
    width: 100%;
    max-width: 100%;
    padding-right: 15px;
    padding-left: 15px;
    margin-right: auto;
    margin-left: auto;
    box-sizing: border-box;
}

h1, h2, h3 {
    color: var(--text-color);
    margin-top: 1.5em;
    margin-bottom: 0.5em;
}

h1 {
    font-size: 2.5em;
    border-bottom: 2px solid var(--accent-color);
    padding-bottom: 0.3em;
}

h2 {
    font-size: 2em;
    color: var(--accent-color);
}

h3 {
    font-size: 1.5em;
}

a {
    color: var(--accent-color);
    text-decoration: underline;
    text-underline-offset: 2px;
    text-decoration-thickness: 1px;
    font-weight: 500;
    transition: all 0.3s ease;
}

a:hover, a:focus {
    color: var(--hover-color);
    text-decoration-thickness: 2px;
    outline: none;
}

a:focus {
    outline: 2px solid var(--accent-color);
    outline-offset: 2px;
}

.section {
    margin-bottom: 2em;
    padding: 1em;
    border: 1px solid var(--border-color);
    border-radius: 5px;
}

.entry {
    margin-bottom: 1.5em;
}

.date {
    color: var(--date-color);
    font-style: italic;
    margin: 0.5em 0;
}

.overview {
    font-weight: 500;
    margin: 0.5em 0;
}

ul {
    margin: 0.5em 0;
    padding-left: 1.5em;
}

li {
    margin: 0.3em 0;
}

hr {
    border: none;
    border-top: 1px solid var(--border-color);
    margin: 2em 0;
}

.theme-switch {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1000;
    display: flex;
    gap: 10px;
}

.theme-switch button {
    background: none;
    border: none;
    font-size: 1.5em;
    cursor: pointer;
    padding: 5px;
    border-radius: 50%;
    transition: background-color 0.3s;
}

.theme-switch button:hover {
    background-color: rgba(128, 128, 128, 0.2);
}

@media (max-width: 600px) {
    body {
        padding: 10px;
    }
    
    h1 {
        font-size: 2em;
    }
    
    h2 {
        font-size: 1.5em;
    }
    
    h3 {
        font-size: 1.2em;
    }
}

/* Navigation styles */
.main-nav {
    display: flex;
    justify-content: center;
    margin: 1rem 0;
}

.main-nav ul {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
    gap: 1rem;
    border-radius: 4px;
    background-color: var(--theme-bg);
    padding: 0.5rem 1rem;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.main-nav li {
    margin: 0;
    padding: 0;
    position: relative;
}

.main-nav a {
    display: block;
    padding: 0.5rem 1rem;
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    border-radius: 4px;
    transition: background-color 0.3s, color 0.3s;
}

.main-nav a:hover {
    background-color: var(--theme-hover);
    color: var(--accent-color);
}

.main-nav a.active {
    background-color: var(--accent-color);
    color: white;
}

/* Dropdown styles */
.main-nav .dropdown {
    position: relative;
    cursor: pointer;
}

.main-nav .dropdown > a::after {
    content: "▼";
    font-size: 0.7em;
    margin-left: 0.5em;
    vertical-align: middle;
}

.main-nav .dropdown-content {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    background-color: var(--theme-bg);
    min-width: 160px;
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    border-radius: 4px;
    padding: 0.5rem 0;
    margin-top: 0.5rem;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s ease, visibility 0s linear 0.2s;
}

.main-nav .dropdown:hover .dropdown-content,
.main-nav .dropdown:focus-within .dropdown-content {
    display: block;
    opacity: 1;
    visibility: visible;
    transition: opacity 0.2s ease, visibility 0s linear 0s;
}

.main-nav .dropdown-content a {
    padding: 0.5rem 1rem;
    display: block;
    text-align: left;
    white-space: nowrap;
}

.main-nav .dropdown-content a.active {
    background-color: var(--accent-color);
    color: white;
}

/* Responsive navigation */
@media (max-width: 600px) {
    .main-nav ul {
        flex-direction: column;
        gap: 0.5rem;
    }
    
    .main-nav a {
        text-align: center;
    }
    
    .main-nav .dropdown-content {
        position: static;
        box-shadow: none;
        margin-top: 0;
        padding-left: 1rem;
    }
}

.read-more {
    display: inline-block;
    margin-top: 0.5em;
    font-weight: 500;
    color: var(--accent-color);
    text-decoration: none;
    border-bottom: 1px solid transparent;
    transition: border-color 0.2s ease;
}

.read-more:hover, .read-more:focus {
    border-bottom-color: var(--accent-color);
    text-decoration: none;
}

.read-more::after {
    content: "→";
    margin-left: 0.3em;
    transition: transform 0.2s ease;
}

.read-more:hover::after, .read-more:focus::after {
    transform: translateX(3px);
}