:root {
      --bg-dark: #1f1f1f;
      --surface-dark: #2c2c2c;
      --text-dark: #eaeaea;
      --muted-dark: #a9a9a9;
      --border-dark: #3a3a3a;

      --bg-light: #f9f9f9;
      --surface-light: #ffffff;
      --text-light: #1f1f1f;
      --muted-light: #555555;
      --border-light: #d0d0d0;

      /* A quiet surface for lines that were unread when the discussions page opened. It is a
         pair because every text colour of a theme is measured against every palette surface of
         that theme; these stay close to the ordinary card while keeping the narrowest readings
         above the contrast floor. */
      --unread-surface-dark: #242b32;
      --unread-surface-light: #f5f9ff;

      --accent: #4db6ff; /* matches tabs accent/selected */
      --accent-light: #007acc;

      /* the colour a refusal is written in, one per theme, and the pair is not decoration :
         the first is chosen for a near-black surface, and read on the white card the light
         theme draws it is a pale pink that a good many people cannot tell from grey. */
      --error-dark: #ff6b6b;
      --error-light: #c62828;

      /* the colour good news is written in, one per theme, and this pair exists for the same
         reason as the one above it. The class it feeds carried a single value for both themes -
         the keyword `green`, which is #008000 - and read in a browser on the dark theme's own
         surfaces that is 2.8 to 1 against the topbar and against the card. That is not a colour
         somebody chose badly, it is a sentence somebody has to lean in to read. The light value
         is that same colour written as a number, so nothing about the light theme moved when the
         pair was introduced ; the dark one is the pastel treatment its partner already uses and
         reads at 8.4 to 1 on the same two surfaces. */
      --success-dark: #6bdd85;
      --success-light: #008000;

      /* The colour a link is written in, one per theme, and this pair exists because the site had
         no link colour at all : nothing in any stylesheet said what a link should look like, so
         every link in a sentence was drawn in the browser's own blue. That is one value for both
         themes, chosen for a white page, and read in a browser it is 9.4 to 1 on the light theme's
         card and 1.5 to 1 on the dark theme's - the worst reading this site has ever produced, and
         it looks deliberate on whichever theme somebody happens to be developing on.
         Both values are the owner's own, chosen by looking at the two themes rather than derived.
         The dark one came from a site whose dark theme gets a great deal more use than this one's
         and reads 4.53 to 1 on the card and 5.35 to 1 on the page behind it - past the 4.5 that
         ordinary text has to reach, and past it by three hundredths on the card, which is worth
         knowing before anybody makes the card any lighter. The light one replaced the browser's
         own blue, which passed comfortably but is not a colour anybody picked ; this one reads
         5.0 to 1 on a white page, so the light theme kept its margin while stopping being an
         accident. */
      --link-dark: #648efc;
      --link-light: #0073be;

      /* A link somebody has already followed, per theme, and the pair is here rather than left to
         the browser for the same reason as the pair above : the browser's own visited colour is a
         dark purple chosen for a white page, and nothing about this site's dark card is consulted.
         The dark value is a muted purple that reads *below* its unvisited partner rather than above
         it, which is the way round that matters - a visited link should recede, and the value that
         stood here before was a paler blue than the unvisited one, so a followed name drew more
         attention than an unfollowed one. The light value is very nearly the body's own text
         colour, which is the same idea taken further : on a white page a followed link stops
         announcing itself at all. */
         The dark value is a lightened form of the muted purple that was asked for. The value as
         given, #6d4b8d, reads 2.02 to 1 on the card and 2.39 on the page - a followed link would
         have been harder to read than the neon blue that started all of this, in the other
         direction. Hue and saturation are kept exactly ; only lightness moved, by the smallest step
         that clears the floor, so it is the same colour and it can be read. */
      --link-visited-dark: #a588c0;
      --link-visited-light: #222222;

      /* A link under the pointer. This began as one value for both themes, since one was what was
         asked for, and it had to become a pair - which is worth writing down, because "one value,
         used twice" is normally the right instinct and here it cannot work at any value.
         The bright cyan reads 7.99 to 1 on the dark card and 1.75 to 1 on a white page. Darkening it
         far enough to clear the floor on white takes it to 3.09 on the card, so it fails on the other
         side instead : there is no single lightness of this hue that a reader can see on both a
         near-black card and a white page. A pair is not a stylistic preference here, it is the only
         arrangement that works.
         The bright value is kept exactly as chosen for the dark theme, where it is excellent. The
         light one is the same hue and saturation darkened to the smallest step that clears the floor
         on white. */
      --link-hover-dark: #64d0ff;
      --link-hover-light: #0079ae;

      /* The outline a gallery card is drawn with when what waits at the other end of Get design is
         not the cutting instructions : red where the page it opens shows the diagram without them,
         orange where it asks to be bought. A free design is drawn plain, so there is no third pair.

         Two values each, for the reason every pair above has two - one is chosen against the near
         black the dark theme draws and the other against the light theme's white page. Read as a
         graphic element rather than as text, which is a 3 to 1 bar : the red pair is the one this
         site already writes refusals in and reads 5.9 and 5.3 to 1, and the orange pair reads 8.2
         and 4.9. They are declared apart from the refusal pair, though the red is the same value
         today, because an outline on a card is not an error and the two are free to move apart. */
      --closed-design-outline-dark: #ff6b6b;
      --closed-design-outline-light: #c62828;
      --paid-design-outline-dark: #ffa14d;
      --paid-design-outline-light: #b25000;
    }