:root {
    --bg-color: #f4f4f9;
    --text-color: #333;
    --container-bg: white;
    --header-text-color: #5a5a5a;
    --btn-bg: #4CAF50;
    --btn-hover-bg: #45a049;
    --category-btn-bg: #e7e7e7;
    --category-btn-text: black;
    --category-btn-hover-bg: #ddd;
    --category-btn-active-bg: #d35400;
    --category-btn-active-text: white;
    --menu-text-color: #d35400;
}

body.dark-mode {
    --bg-color: #121212;
    --text-color: #e0e0e0;
    --container-bg: #1e1e1e;
    --header-text-color: #b0b0b0;
    --btn-bg: #004d40;
    --btn-hover-bg: #00796b;
    --category-btn-bg: #333;
    --category-btn-text: #e0e0e0;
    --category-btn-hover-bg: #444;
    --category-btn-active-bg: #d35400;
    --category-btn-active-text: white;
    --menu-text-color: #e67e22;
}

body {
    font-family: 'Helvetica Neue', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    margin: 0;
    transition: background-color 0.3s, color 0.3s;
}

header {
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 40px;
    background-color: var(--container-bg);
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    position: fixed;
    top: 0;
    left: 0;
    z-index: 1000;
}

.navbar {
    display: flex;
    align-items: center;
}

.nav-logo {
    color: var(--header-text-color);
    font-size: 1.5em;
    font-weight: bold;
    text-decoration: none;
}

.nav-menu {
    list-style: none;
    display: flex;
    margin: 0;
    padding: 0 0 0 40px;
}

.nav-item {
    margin-left: 20px;
}

.nav-link {
    color: var(--text-color);
    text-decoration: none;
    font-size: 1em;
    transition: color 0.3s;
}

.nav-link:hover {
    color: var(--menu-text-color);
}

main.main-content {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    padding-top: 80px; /* Adjust for fixed header */
}

.dark-mode-toggle {
    position: relative;
    display: inline-block;
    width: 60px;
    height: 34px;
}

.dark-mode-toggle input {
    opacity: 0;
    width: 0;
    height: 0;
}

.dark-mode-toggle label {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #ccc;
    transition: .4s;
    border-radius: 34px;
}

.dark-mode-toggle label:before {
    position: absolute;
    content: "";
    height: 26px;
    width: 26px;
    left: 4px;
    bottom: 4px;
    background-color: white;
    transition: .4s;
    border-radius: 50%;
}

input:checked + label {
    background-color: #2196F3;
}

input:checked + label:before {
    transform: translateX(26px);
}

.container {
    text-align: center;
    background: var(--container-bg);
    padding: 40px;
    border-radius: 15px;
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
    transition: transform 0.3s, background-color 0.3s;
    max-width: 800px;
    width: 90%;
}

.container:hover {
    transform: translateY(-5px);
}

.container p {
    line-height: 1.6;
}

.contact-info a {
    color: var(--menu-text-color);
    text-decoration: none;
}

h1 {
    font-size: 2.5em;
    color: var(--header-text-color);
    margin-bottom: 20px;
}

button {
    background-color: var(--btn-bg);
    color: white;
    padding: 15px 32px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    font-size: 16px;
    margin: 20px 0;
    cursor: pointer;
    border: none;
    border-radius: 8px;
    transition: background-color 0.3s, box-shadow 0.3s;
}

button:hover {
    background-color: var(--btn-hover-bg);
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}

#category-buttons {
    margin-bottom: 20px;
}

.category-btn {
    background-color: var(--category-btn-bg);
    color: var(--category-btn-text);
    padding: 10px 20px;
    margin: 5px;
    border-radius: 20px;
    border: 2px solid transparent;
}

.category-btn:hover {
    background-color: var(--category-btn-hover-bg);
}

.category-btn.active {
    background-color: var(--category-btn-active-bg);
    color: var(--category-btn-active-text);
    border-color: #a04000;
}

h2 {
    font-size: 2em;
    color: var(--menu-text-color);
    min-height: 50px;
    margin-top: 20px;
}

.footer {
    width: 100%;
    background-color: var(--container-bg);
    padding: 20px 0;
    text-align: center;
    box-shadow: 0 -2px 5px rgba(0,0,0,0.1);
}

.footer-content {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
}

.footer-links {
    list-style: none;
    display: flex;
    padding: 0;
    margin-top: 10px;
}

.footer-links li {
    margin: 0 15px;
}

.footer-links a {
    color: var(--text-color);
    text-decoration: none;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: var(--menu-text-color);
}

@media (max-width: 768px) {
    header {
        flex-direction: column;
        padding: 10px 20px;
    }
    .nav-menu {
        padding-left: 0;
        margin-top: 10px;
    }
    main.main-content {
        padding-top: 120px; /* Adjust for taller header */
    }
}

@media (max-width: 600px) {
    .container {
        width: 90%;
        padding: 20px;
    }
    h1 {
        font-size: 2em;
    }
    h2 {
        font-size: 1.5em;
    }
}