* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body {
    font-family: Arial, sans-serif;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    background: #f4f4f4;
}
header {
    background: #222;
    color: white;
    padding: 1rem;
    height: 10vh;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
}
.logo {
    font-size: 1.5rem;
    font-weight: bold;
}
.menu {
    list-style: none;
    display: flex;
    gap: 1rem;
}
.menu a {
    color: white;
    text-decoration: none;
}
.menu a.active {
    text-decoration: underline;
}
.auth-links {
    margin-right: 1rem;
}
.auth-links a {
    color: white;
    text-decoration: none;
    margin-left: 0.5rem;
}
.auth-links a:hover {
    text-decoration: underline;
}
.container {
    flex: 1;
    display: flex;
    padding-top: 10vh; /* Отступ для header */
    padding-bottom: 10vh; /* Отступ для footer */
    margin-left: 10%; /* Отступ для left-sidebar */
    margin-right: 10%; /* Отступ для right-sidebar */
}
.left-sidebar {
    width: 10%;
    background: #fff;
    padding: 1rem;
    border-right: 1px solid #ddd;
    position: fixed;
    top: 10vh; /* Под header */
    left: 0;
    bottom: 10vh; /* Над footer */
    overflow-y: auto;
    z-index: 999;
}
.right-sidebar {
    width: 10%;
    background: #fff;
    padding: 1rem;
    border-left: 1px solid #ddd;
    position: fixed;
    top: 10vh;
    right: 0;
    bottom: 10vh;
    overflow-y: auto;
    z-index: 999;
}
.content {
    flex: 1;
    background: white;
    padding: 1rem;
    min-height: calc(100vh - 20vh); /* Высота без header и footer */
}
.product-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
}
.product-card {
    background: white;
    padding: 1rem;
    border: 1px solid #ddd;
    width: 200px;
    text-align: center;
    flex: 1 1 200px;
}
.banner {
    background: #007BFF;
    color: white;
    padding: 1rem;
    text-align: center;
}
.chat-button {
    margin-top: 1rem;
    text-align: center;
    color: #007BFF;
    cursor: pointer;
}
footer {
    background: #222;
    color: white;
    text-align: center;
    padding: 1rem;
    height: 10vh;
    position: fixed;
    bottom: 0;
    width: 100%;
    z-index: 1000;
}
footer .social-links a {
    color: white;
    margin: 0 0.5rem;
}