div.header {
    width: 100%;
    height: var(--header-height);
    z-index: 100;
    justify-content: center;
    align-items: center;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: black;
}

div.header_content {
    height: var(--header-height);
    display: flex;
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
    width: var(--container-width-percentage);
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 var(--spacing-xs);
}

div.head_logo {
    height: var(--header-height);
    display: flex;
    align-items: center;
}

div.head_logo img {
    height: var(--logo-height);
    margin-left: var(--spacing-xs);
}

div.head_menu {
    display: flex;
    flex-direction: row;
    margin-right: var(--spacing-md);
}

.head_menu .menu_item {
    margin: 0 var(--spacing-sm);
    font-size: var(--font-size-sm);
}

.head_menu .menu_item a {
    color: white;
    text-decoration: none;
    transition: color var(--transition-time);
}

.head_menu .menu_item a:hover {
    color: rgb(59, 128, 255);
}

@media screen and (max-width: 768px) {
    div.header {
        height: auto;
        padding: var(--spacing-xs) 0;
    }
    
    div.header_content {
        height: auto;
        flex-direction: column;
    }
    
    div.head_logo {
        height: auto;
        margin-bottom: var(--spacing-xs);
    }
    
    div.head_menu {
        width: 100%;
        justify-content: space-around;
        margin-right: 0;
        flex-wrap: nowrap;
    }
    
    .head_menu .menu_item {
        margin: var(--spacing-xxs) var(--spacing-xxs);
        font-size: var(--font-size-xs);
        white-space: nowrap;
    }
}

@media screen and (max-width: 480px) {
    div.header {
        height: auto;
        padding: var(--spacing-xxs) 0;
    }
    
    div.header_content {
        height: auto;
        flex-direction: column;
    }
    
    div.head_logo {
        height: auto;
        margin-bottom: var(--spacing-xxs);
    }
    
    div.head_menu {
        width: 100%;
        justify-content: space-between;
        margin-right: 0;
        flex-wrap: nowrap;
    }
    
    .head_menu .menu_item {
        margin: var(--spacing-xxs) var(--spacing-xxs);
        font-size: calc(var(--font-size-xs) - 0.1rem);
        white-space: nowrap;
    }
}