:root {
    --bg-color: #faf9f6;
    --text-color: #222;
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --sidebar-width: 16em;
    --content-max-width: 42em;
    --breakpoint: 48em;
}

* {
    box-sizing: border-box;
}

body {
    background: var(--bg-color);
    font-family: var(--font-family);
    color: var(--text-color);
    font-size: 0.85em;
    margin: 0;
    padding: 0;
}

h1 {
    font-size: 1.15em;
    font-weight: 700;
    margin: 1.2em 0 0.7em 0;
}

h2 {
    font-size: 1.05em;
    font-weight: 600;
    margin: 1.1em 0 0.6em 0;
}

h3 {
    font-size: 0.95em;
    font-weight: 500;
    margin: 1em 0 0.5em 0;
}

h4 {
    font-size: 0.9em;
    font-weight: 500;
    margin: 0.9em 0 0.4em 0;
}

/* Layout containers */
.wrapper {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.content {
    padding: 0 2em 2em 2em;
    flex: 1;
}

/* Header */
.header {
    padding: 2em;
}

.header h2 {
    margin: 0 0 0.5em 0;
}

.header h2 a {
    text-decoration: none;
    color: var(--text-color);
}

.header .description {
    margin-bottom: 1em;
}

.header .description p {
    margin: 0;
}

/* Navigation */
.header nav {
    display: flex;
    flex-wrap: wrap;
    gap: 1em;
}

.header nav a {
    color: var(--text-color);
    text-decoration: none;
    font-weight: bold;
}

.header nav a:hover {
    text-decoration: underline;
}

/* Footer */
.footer {
    padding: 2em;
    display: flex;
    flex-wrap: wrap;
    gap: 1em;
    font-size: 0.85em;
}

.footer a {
    color: var(--text-color);
    text-decoration: none;
    opacity: 0.6;
    transition: opacity 0.2s;
    display: inline-flex;
    align-items: center;
}

.footer a:hover {
    opacity: 1;
}

/* Desktop layout with sidebar */
@media (min-width: 48em) {
    .wrapper {
        flex-direction: row;
    }

    .header {
        position: sticky;
        top: 0;
        width: var(--sidebar-width);
        height: 100vh;
        overflow-y: auto;
        flex-shrink: 0;
        padding: 2em 1.5em;
    }

    .header nav {
        flex-direction: column;
        gap: 0.5em;
    }

    .footer {
        position: fixed;
        bottom: 0;
        left: 0;
        width: var(--sidebar-width);
        padding: 1.5em;
        background: var(--bg-color);
    }

    .content {
        flex: 1;
        padding: 2em;
        overflow-y: auto;
        max-height: 100vh;
    }

    .content>* {
        max-width: var(--content-max-width);
    }
}