youpilat13 youpilat13 - 2 months ago 9
CSS Question

Mathjax - Add offset for the target "\eqref" link of equation when there is a top fixed menu

I try to implement with "pure" CSS solution or with Javascript a way
to add an offset for Matjax anchor links on equations.

When I scroll down on my page, I get a fixed top menu that appears. I handle this behavior with Javascript like this :

$(window).bind("load", function () {

$('a[href*="#"]').click(function(event) {
event.preventDefault();
if (location.pathname.replace(/^\//,'') == this.pathname.replace(/^\//,'') && location.hostname == this.hostname) {
var target = $(this.hash);
target = target.length ? target : $('[name=' + this.hash.slice(1) +']');
if (target.length) {
var hash = this.hash;
$('html,body').animate({ scrollTop: target.offset().top - 55 }, 300, function() {
href = window.location.href;
history.pushState({page:href}, null, href.split('#')[0]+hash);
});
return false;
}
}
});

$(window).bind('popstate', function(event) {
var state = event.originalEvent.state;
var target = window.location.href.split('#');
var href = target[0];
if (state) {
$('html,body').animate({ scrollTop: 0 }, 300, function() {
history.replaceState({}, null, href);
});
}
});


Everything works fine but now, I would like to add a functionality with which I could have a good offset when I click on anchor links for MahJax equations ( this happens when I have
\eqref
references into my HTML page that refer to MathJax equations).

From this link, I tried to use a pure CSS solution by adding in my CSS style :

a[name*="mjx"] {
display: block;
position: relative;
top: -100px;
visibility: hidden;
}


I have set
a[name*="mjx"]
because the pattern "
mjx
" appears when mouse is over Mathjax anchor links (with Firefox).

But this solution doesn't seem to work.

I have also to add directly into
\begin{equation}
environnement a
\cssId{anchor_eq}{my equation}
instruction, with :

#anchor_eq {
display: block;
position: relative;
top: -100px;
visibility: hidden;
}


but without success.

You can check an example of my issue on this following link.

As you can seee, if I click on the starting menu (on the top of page, i.e on one of links "
1.Introduction
" "
2.Content components of the Universe
" etc ...), I get a valid offset so that links are not hidden by top fixed menu.

But concerning the "
\eqref
" references, if I click on "
mjx-eqn-eq
" links, equations are hidden by top fixed menu.

If anyone could see a solution, this would be nice,

Thanks in advance.

UPDATE 1 :

I have tried to set what Davide Cervone said.

Noticing that target link of anchor shows as (in inspector) :

<div class="MathJax_Display"></div>


So I have added the following CSS (after MathJax is loaded):

.MathJax_Display {
display: block;
content: "";
margin-top: -100px;
height: 100px;
visibility: hidden;
}


But this doesn't work, after clicking on label links (i.e
\eqref
), equations are still hidden by top fixed menu.

I keep on searching a solution.

Answer

If you wait to make your change to the <a> tags until after MathJax runs, then your code will pick up the MathJax links as well and you won't have to handle them separately. One way would be to replace $(window).bind("load", function () { with MathJax.Hub.Queue(function () { (provided this appears after the <script> that loads MathJax.js itself).