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

:root {
    --primary-color: #007bff;
    --secondary-color: #6c757d;
    --background-color: #f8f9fa;
    --text-color: #343a40;
    --light-gray: #f1f1f1;
    --white: #fff;
    --shadow: 0 5px 15px rgba(0,0,0,0.1);
}

body {
    font-family: 'Poppins', sans-serif;
    margin: 0;
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.6;
}

header {
    background-color: var(--primary-color);
    color: var(--white);
    padding: 1.5em 2em;
    text-align: center;
}

header h1 {
    margin: 0;
    font-weight: 700;
    font-size: 2.5em;
}

.container {
    display: flex;
    margin: 2em;
}

aside {
    width: 200px;
    margin-right: 2em;
}

aside nav ul {
    list-style-type: none;
    padding: 0;
}

aside nav ul li a {
    display: block;
    padding: 1em;
    background-color: var(--white);
    color: var(--primary-color);
    text-decoration: none;
    margin-bottom: 0.5em;
    border-radius: 5px;
    transition: background-color 0.3s ease;
}

aside nav ul li a:hover,
aside nav ul li a.active {
    background-color: var(--primary-color);
    color: var(--white);
}

main {
    flex: 1;
}

.content {
    display: none;
    background-color: var(--white);
    padding: 2em;
    border-radius: 10px;
    box-shadow: var(--shadow);
    animation: fadeIn 0.5s ease;
}

.content.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

footer {
    background-color: var(--text-color);
    color: var(--white);
    padding: 1.5em;
    text-align: center;
    margin-top: 2em;
}