Center Left-Aligned Text to Middle of Screen in Custom Desktop Burger Menu

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Hello,

I have managed to create a desktop burger menu using the following code:

@media only screen and (min-width: 760px) {
  
	.header .header-burger {
		display:flex; margin: 30px;
  	} 
  
	.header-nav {display:none}
  
	.header--menu-open .header-menu {
      display: flex; 
      opacity: 1; visibility: visible;
      text-align: left;
  	}
  
	.header-menu-actions {
      display: none;
  	}
  
	.header-menu-cta {
		display: none;
	}
  
	.header-menu-nav-item a {
    	font-size: 45px;
    	line-height: .8;
	}
}

However, the text appears on the far left side of the screen due to it being left-aligned. I would like to keep the text left-aligned, but center it to the screen. Any help would be appreciated! 

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