I wasn't paying attention when this happened, but all of a sudden the color theme changed to orange when I try looking at the posts listing. Anything else is still the original blue colors: the navigation bar, the other pages like account, comments, tags, etc. even when I select an individual post. It's just the posts listing that appears orange.
Does anyone know a quick fix to get it back to blue?

There should be a "Mode" selector which needs to be set back to "View", I think you've currently got it toggled to "Add to Set"

The drop-down is below the search bar on desktop and below the posts listing on mobile layout.

faucet said:
There should be a "Mode" selector which needs to be set back to "View", I think you've currently got it toggled to "Add to Set"

The drop-down is below the search bar on desktop and below the posts listing on mobile layout.

Oh thanks! I use that a lot so I must not have noticed the initial change.
Is there any way I can get it so it still shows blue when I still have it on the "Add to Set" mode?

assowobserver said:
Oh thanks! I use that a lot so I must not have noticed the initial change.
Is there any way I can get it so it still shows blue when I still have it on the "Add to Set" mode?

Custom style sheets. For example code, I think the different schemes have lists of colors they change.
Example of setting custom colors:

body {
--color-tag-lore:#5F6;
--color-tag-lore-alt:#FFFFFF;
}

This makes it easier for me to read lore tags which had too close of a foreground color to the background.

https://e621.net/forum_topics/25716 Forum post from a revamp several years back.

To find the specific tag on some (not just e621) page, you'd note "data-mode-menu" in DOM Inspector (page is ID). This changes from view to edit and so on, when you change the colors. From looking through one of source files (in style editor), I see this:

#page[data-mode-menu=edit] {
  background-color:#828028
}
#page[data-mode-menu=add-fav] {
  background-color:#104e17
}
#page[data-mode-menu=remove-fav] {
  background-color:#07240b
}
#page[data-mode-menu=add-to-set] {
  background-color:#a51
}
#page[data-mode-menu=remove-from-set] {
  background-color:#7c3e0c
}
#page[data-mode-menu=vote-up] {
  background-color:#288233
}
#page[data-mode-menu=vote-down] {
  background-color:#822828
}
#page[data-mode-menu=rating-s] {
  background-color:#1a421f
}
#page[data-mode-menu=rating-q] {
  background-color:#650
}
#page[data-mode-menu=rating-e] {
  background-color:#a71c1c
}
#page[data-mode-menu=tag-script] {
  background-color:#4f114f
}
#page[data-mode-menu=remove-parent] {
  background-color:#38f
}
#page[data-mode-menu=lock-rating] {
  background-color:#aa3
}
#page[data-mode-menu=lock-note] {
  background-color:#3aa
}
#page[data-mode-menu=approve] {
  background-color:#48c
}
#page[data-mode-menu=delete] {
  background-color:#4e1010
}
#page[data-mode-menu=undelete] {
  background-color:#818
}
#page[data-mode-menu=unflag] {
  background-color:#304
}

You can just customize those to all be blue (#020f23) if you want. It takes 3 and 6-character color codes, where in this example, it's red=02, green=0f, blue=23. You could also use #012 to get approximately the same.

Searching for "div#page" in that style sheet editor shows this:

div#page {
  background-color:#152f56;
  background-color:var(--color-foreground);
  background-image:var(--image-foreground);
  background-position:var(--image-foreground-position);
  background-repeat:var(--image-foreground-repeat);
  border-radius:6px;
  margin:0 1rem;
  overflow:visible;
  padding:.5rem;
  padding-bottom:var(--content-padding-bottom)
}

I was curious since I didn't see a 'view' color setting. It inherents it from that variable, '--color-foreground', apparently.