how to change backgroundcolor for read more in inline block

Hi, I’m trying to edit the read more link in a post on my website. Change the background color.

This is what it looks like now:

https://www.shmamassage.nl/massage-informatie/vrouwen-in-de-overgang

And this is what the style css looks like: (theme Tempera, latest version):

/* Continue Reading Links */

a.continue-reading-link {
display:inline-block;
position:relative;
width:auto;
float:none;
padding:0px 8px 0px 8px;
border-bottom:2px solid transparent;
margin-top: 3px;
line-height:1.6em;
font-size:16px;
text-transform:none;
font-style:normal;
clear:both;
}

a.continue-reading-link:after {
content:"";

ETC ETC….

I already changed the font-size and padding and the text-transform.
But I can’t seem to change background color.
I tried adding to the code : background-color:#fff0b5; or back-color:#fff0b5; or just color:#etc.etc. .

And also tried different writing: with space, without space between the : and # . And also color values with and without the # .

Nothing worked.

I already read the codex.www.ads-software.com/continue-reading…nothing I tried worked.

The theme settings only allows for the text to be changed to your own (in my case :”lees meer” in Dutch).

But I cannot find how to change the background color.
In the support area of the tempera theme, people are struggling with the same issue, no answer jet.

Anyone any ideas???
Or should I change code in another file??

Please help!