Trouble with link to internal page with anchor elements for Technical Documentation Page

I am stuck on something with the Technical Document Project. For the internal links I am trying to create for my side nav bar to jump to the section id="#Mies_Van_Der_Rohe" from the <href="#Mies_Van_Der_Rohe"> element. However, when I click ‘Mies Van Der Rohe’ on the left side nav bar in the browser the main site doesn’t go to the designated id="#Mies_Van_Der_Rohe". The href and it’s corresponding id, further down in the window, are both identical. I’ve tried taking rel="" in and out of the original href. I’ve tried solving this but I am stuck here. Could there be something wrong with my CSS. Here’s the codepen link: https://codepen.io/holmedw/pen/yRNOrG

If I’m asking this question prematurely I understand. However I’ve compared my code to a fellow FreeCodeCamper and the sample code provided by FCC with similar results.

In some cases you are not using the same case or subbing - for _.
id="alvaro-siza" not the same as href="#Alvaro_Siza"

In case of id="#Mies_Van_Der_Rohe" the # is not included in the id, just in href. # indicates to href that the link to something local to the page
Should be id="Mies_Van_Der_Rohe"