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

body {
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
    background-color: #f4f4f9;
    color: #333;
    scroll-behavior: smooth;
}

/* Main Container */
.container {
    display: grid;
    grid-template-areas:
        "header"
        "sidebar"
        "content"
        "footer";
    grid-template-columns: 1fr;
    grid-template-rows: auto;
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    gap: 20px;
}

/* Header Section */
header {
    grid-area: header;
    background-color: #4a90e2;
    color: #fff;
    text-align: center;
    padding: 20px 0;
    border-radius: 5px;
}

header .title {
    font-size: 2rem;
    font-weight: bold;
}

/* Sidebar Navigation */
.sidebar {
    grid-area: sidebar;
    background-color: #fff;
    border: 1px solid #ddd;
    border-radius: 5px;
    padding: 20px;
    position: sticky;
    top: 20px;
}

.sidebar ul {
    list-style: none;
}

.sidebar ul li {
    margin-bottom: 10px;
}

.sidebar ul li a {
    text-decoration: none;
    color: #4a90e2;
    font-weight: bold;
    padding: 10px;
    display: block;
    border-radius: 5px;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.sidebar ul li a:hover,
.sidebar ul li a.active {
    background-color: #4a90e2;
    color: #fff;
}

/* Content Section */
.content-section {
    grid-area: content;
    background-color: #fff;
    border: 1px solid #ddd;
    border-radius: 5px;
    padding: 20px;
    margin-bottom: 20px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    min-height: 100px;
    display: none; /* Hidden by default */
}

.content-section.visible {
    display: block;
}

/* Footer Section */
footer {
    grid-area: footer;
    background-color: #4a90e2;
    color: #fff;
    text-align: center;
    padding: 10px;
    border-radius: 5px;
}

/* Responsive Design */
@media (min-width: 768px) {
    .container {
        grid-template-areas:
            "header header"
            "sidebar content"
            "footer footer";
        grid-template-columns: 1fr 3fr;
        grid-template-rows: auto;
        gap: 20px;
    }
}

/* Scroll Adjustment */
:target {
    scroll-margin-top: 100px;
}