:root {
    --bg-light: #f9f9f9;
    --text-light: #333;
    --accent-light: #007bff;
    --bg-dark: #121212;
    --text-dark: #eee;
    --accent-dark: #64b5f6;
    --transition: all 0.3s ease;
    --card-shadow-light: 0 8px 32px rgba(0, 0, 0, 0.1);
    --card-shadow-dark: 0 8px 32px rgba(0, 0, 0, 0.3);
    --blur-amount: 20px;
    --logo-height: 70px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    margin: 0;
    padding: 0;
    background-color: var(--bg-light);
    color: var(--text-light);
    transition: var(--transition);
    min-height: 100vh;
}

body.dark-mode {
    background-color: var(--bg-dark);
    color: var(--text-dark);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.1rem;
    background: linear-gradient(135deg, rgba(224, 247, 250, 0.5), rgba(194, 233, 251, 0.5));
    backdrop-filter: blur(var(--blur-amount));
    -webkit-backdrop-filter: blur(var(--blur-amount));
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.dark-mode nav {
    background: linear-gradient(135deg, rgba(38, 50, 56, 0.7), rgba(55, 71, 79, 0.7));
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 4px 6px -1px rgba(255, 255, 255, 0.1);
}

nav a {
    display: none;
    margin: 0 15px;
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
    padding: 10px 15px;
    border-radius: 20px;
    box-shadow: inset 0 0 0 1px rgba(0, 0, 0, 0.1);
}

.dark-mode nav a {
    box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.1);
}

nav a:hover {
    background-color: rgba(0, 0, 0, 0.1);
    transform: translateY(-1px);
}

.dark-mode nav a:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.hamburger-btn {
    background: none;
    border: none;
    font-size: 1.5em;
    cursor: pointer;
    color: inherit;
    transition: var(--transition);
    padding: 8px;
    border-radius: 8px;
}

.hamburger-btn:hover {
    background-color: rgba(0, 0, 0, 0.1);
}

.dark-mode .hamburger-btn:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

#sidebar {
    position: fixed;
    top: 0;
    left: -300px;
    width: 300px;
    height: 100vh;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(var(--blur-amount));
    -webkit-backdrop-filter: blur(var(--blur-amount));
    transition: var(--transition);
    padding-top: 20px;
    z-index: 1001;
}

.dark-mode #sidebar {
    background: rgba(39, 39, 39, 0.9);
}

#sidebar.open {
    left: 0;
    box-shadow: 2px 0 12px rgba(0, 0, 0, 0.1);
}

.sidebar-logo {
    display: block;
    width: 180px;
    height: auto;
    margin: 0 auto 20px;
    padding: 10px 20px;
    object-fit: contain;
    max-height: 60px;
}

.menu {
    list-style: none;
    padding: 0;
    margin: 0;
    border-top: 1px solid rgba(0, 0, 0, 0.1);
}

.dark-mode .menu {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.menu li {
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.dark-mode .menu li {
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.menu li a {
    display: block;
    padding: 15px 20px;
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

.menu li a:hover {
    background-color: rgba(0, 0, 0, 0.1);
}

.dark-mode .menu li a:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.submenu {
    list-style: none;
    padding-left: 20px;
    display: none;
    background: rgba(0, 0, 0, 0.03);
}

.dark-mode .submenu {
    background: rgba(255, 255, 255, 0.03);
}

.menu li:hover .submenu {
    display: block;
}

.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(5px);
    -webkit-backdrop-filter: blur(5px);
    display: none;
    z-index: 1000;
    transition: var(--transition);
}

.overlay.active {
    display: block;
}

.content {
    transition: var(--transition);
    position: relative;
/*     max-width: 2600px; */
    margin: 0 auto;
 /*    padding: 0px; */
}

.content.sidebar-open {
    transform: translateX(300px);
}

.box {
    background: rgba(255, 255, 255, 0.2);
    border-radius: 16px;
    box-shadow: var(--card-shadow-light);
    backdrop-filter: blur(var(--blur-amount));
    -webkit-backdrop-filter: blur(var(--blur-amount));
    border: 1px solid rgba(255, 255, 255, 0.3);
    padding: 20px;
    margin: 5px;
    transition: var(--transition);
}

.dark-mode .box {
    background: rgba(39, 39, 39, 0.3);
    box-shadow: var(--card-shadow-dark);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.toggle-switch {
    position: relative;
    display: inline-block;
    width: 48px;
    height: 28px;
    margin-left: 10px;
    user-select: none;
    -webkit-user-select: none;
}

.switch {
    position: relative;
    display: inline-block;
    width: 48px;
    height: 28px;
    user-select: none;
    -webkit-user-select: none;
}

.switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #ccc;
    transition: .4s;
    border-radius: 28px;
}

.slider:before {
    position: absolute;
    content: "";
    height: 18px;
    width: 18px;
    left: 4px;
    bottom: 5px;
    background-color: white;
    transition: .4s;
    border-radius: 50%;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

input:checked + .slider {
    background-color: var(--accent-light);
}

.dark-mode input:checked + .slider {
    background-color: var(--accent-dark);
}

input:checked + .slider:before {
    transform: translateX(22px);
}

[data-aos] {
    transition-property: transform, opacity;
    transition-timing-function: cubic-bezier(0.23, 1, 0.32, 1);
}

footer {
    text-align: center;
    padding: 20px;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(var(--blur-amount));
    -webkit-backdrop-filter: blur(var(--blur-amount));
    margin-top: auto;
}

.dark-mode footer {
    background: rgba(0, 0, 0, 0.8);
}

.error-message {
    background: rgba(255, 73, 73, 0.1);
    color: #ff4949;
    padding: 1rem;
    border-radius: 8px;
    text-align: center;
    margin: 1rem 0;
}

.dark-mode .error-message {
    background: rgba(255, 73, 73, 0.2);
    color: #ff7373;
}

.logo {
    height: var(--logo-height);
    width: auto;
    margin-right: 10px;
    vertical-align: middle;
    transition: var(--transition);
    object-fit: contain;
}

@media (min-width: 769px) {
    nav a {
        display: inline-block;
    }

    .hamburger-btn,
    #sidebar,
    .overlay {
        display: none;
    }

    .content {
        margin-left: 0;
    }

    .content.sidebar-open {
        transform: none;
    }
}

@media (max-width: 768px) {
    nav {
        justify-content: flex-start;
        padding: 8px 16px;
        align-items: center;
    }

    .nav-links {
        display: none;
    }

    .logo {
        height: calc(var(--logo-height) - 5px);
        margin-right: auto;
    }

    .toggle-switch {
        order: 1;
        margin: 0 12px;
        transform: translateY(1px);
    }

    .hamburger-btn {
        order: 2;
        padding: 8px;
        font-size: 1.4em;
    }

    body {
        backdrop-filter: blur(5px);
        -webkit-backdrop-filter: blur(5px);
    }

    #content {
        background: rgba(255, 255, 255, 0.1);
    }

    .dark-mode #content {
        background: rgba(0, 0, 0, 0.1);
    }
}