:root {
    --primary-color: #277ab9;
    --primary-dark: #225f93;
    --primary-darker: #1a4f7d;
    --text-color: #333;
    --bg-color: #F2F6FA;
    --white: #fff;
    --shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
    --nav-width: 250px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    background-color: var(--bg-color);
    color: var(--text-color);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    overflow-x: hidden;
}

img, video, iframe {
    max-width: 100%;
    height: auto;
    display: block;
}

@media (min-width: 768px) {
    img:not(.logo, .social-links img, .toolbar img, .submenu img, nav img),
    video:not(.video-container video) {
        max-width: 50vw;
    }
}

@media (max-width: 767px) {
    img:not(.logo, .social-links img, .toolbar img, .submenu img, nav img),
    video:not(.video-container video) {
        max-width: 100%;
    }
}

h1, h2, h3, h4, h5, h6 {
    color: var(--text-color);
    line-height: 1.2;
    margin-bottom: 1rem;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }

header {
    background-color: var(--primary-color);
    color: var(--white);
    padding: 15px;
    box-shadow: var(--shadow);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    width: 100%;
}

.header-content {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    position: relative;
}

.logo {
    max-width: 150px;
    margin: 20px auto 6px;
}

.language-selector {
    position: absolute;
    right: 15px;
    top: 15px;
}

.language-selector select {
    padding: 5px;
    font-size: 14px;
    background-color: var(--primary-color);
    color: var(--white);
    border: none;
    cursor: pointer;
    transition: var(--transition);
}

.language-selector select:hover {
    background-color: var(--primary-dark);
}

nav {
    position: fixed;
    left: 0;
    width: var(--nav-width);
    background-color: var(--primary-color);
    font-size: 1.1em;
    overflow-y: auto;
    height: 100%;
}

.nav-links {
    display: flex;
    flex-direction: column;
    padding-left: 10px;
}

nav a {
    padding: 10px 15px;
    text-decoration: none;
    font-weight: bold;
    color: var(--white);
    transition: var(--transition);
}

nav a:hover {
    background-color: var(--primary-dark);
}

.menu-bar {
    display: flex;
    background-color: var(--text-color);
}

.submenu {
    display: none;
    position: absolute;
    background-color: #444;
    min-width: 180px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.2);
}

.submenu a {
    display: block;
    padding: 10px;
    color: var(--white);
    text-decoration: none;
    transition: var(--transition);
}

.submenu a:hover {
    background-color: #b84040;
}

.menu-item:hover .submenu {
    display: block;
}

main {
    padding: 2rem 1rem;
    margin-left: var(--nav-width);
}

.toolbar button:hover {
    background-color: #b84040;
}

footer {
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--primary-color);
    color: var(--white);
    text-align: center;
    padding: 1rem;
}

.social-links {
    position: absolute;
    bottom: 20px;
    right: 20px;
    display: flex;
    gap: 10px;
}

@media (max-width: 767px) {
    header {
        position: fixed;
        top: 0;
        width: 100%;
        height: 220px;
        z-index: 1000;
    }

    .hamburger {
        display: block;
        position: absolute;
        left: 15px;
        top: 170px;
    }

    .logo { display: none; }
}