@import url('https://fonts.googleapis.com/css2?family=Lato:wght@300;400;700&family=Open+Sans:wght@400;600&display=swap');

:root {
    --primary-color: #1e6c93;
    --secondary-color: #185676;
    --bg-color: #ffffff;
    --text-color: #333333;
    --accent-color: #e8f0fe;
    --nav-width: 250px;
    --header-height: 60px;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Lato', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Header & Mobile Nav Bar */
header {
    background-color: var(--primary-color);
    color: white;
    padding: 0 1rem;
    height: var(--header-height);
    display: flex;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

header h1 {
    font-size: 1.5rem;
    font-weight: 300;
}

/* Layout */
.wrapper {
    display: flex;
    flex: 1;
}

/* Sidebar Navigation */
nav {
    width: var(--nav-width);
    background-color: #f8f9fa;
    border-right: 1px solid #e9ecef;
    padding: 1.5rem 1rem;
    overflow-y: auto;
    position: sticky;
    top: var(--header-height);
    height: calc(100vh - var(--header-height));
}

nav ul {
    list-style: none;
}

nav li {
    margin-bottom: 0.5rem;
}

nav a {
    text-decoration: none;
    color: var(--text-color);
    font-size: 0.95rem;
    display: block;
    padding: 0.5rem 0.75rem;
    border-radius: 4px;
    transition: all 0.2s;
}

nav a:hover, nav a.active {
    background-color: var(--accent-color);
    color: var(--primary-color);
}

nav .sub-menu {
    padding-left: 1.5rem;
    margin-top: 0.25rem;
}

/* Main Content */
main {
    flex: 1;
    padding: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

main section {
    margin-bottom: 2rem;
}

h1, h2, h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

h1 { font-size: 2.2rem; font-weight: 300; }
h2 { font-size: 1.8rem; font-weight: 400; border-bottom: 1px solid #eee; padding-bottom: 0.5rem; }

p {
    margin-bottom: 1rem;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
    margin: 1.5rem 0;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}

/* Footer */
footer {
    background-color: #f8f9fa;
    padding: 1.5rem;
    text-align: center;
    font-size: 0.85rem;
    color: #6c757d;
    border-top: 1px solid #e9ecef;
}

/* Responsive */
@media (max-width: 768px) {
    .wrapper {
        flex-direction: column;
    }
    nav {
        width: 100%;
        height: auto;
        position: static;
        border-right: none;
        border-bottom: 1px solid #eee;
    }
    main {
        padding: 1.5rem;
    }
}