/* ===========================================================================
   C Sources · the cover
   ---------------------------------------------------------------------------
   THIS FILE USED TO BE `sources-confluence.css`, and the rename is the whole
   record of what changed on 19 September. The chapter's cover carried an
   animated motif, a field of citation rules converging into one archive thread,
   and it carried the chapter's diffusion field behind that; both are gone,
   along with the canvas they were drawn on and the control that paused them.
   What is left is the cover's own composition, which never belonged to the
   motif: the mauve letter held at the upper left of an oversized title, the
   description beneath it, and the arrow down to the bibliography.

   THE COVER IS SHORTER THAN IT WAS, AND IT IS NO LONGER A PROPORTION OF THE
   WINDOW, which is the motif's departure rather than a separate decision. A
   full viewport with the lockup held at two thirds of its height is a
   composition around something, and what it was around was the drawing;
   without it the reader is given a screen of ground to scroll past before the
   chapter begins.

   The lockup used to be seated at a percentage of that height, which works for
   as long as the height is a percentage of the window and stops working the
   moment either number is capped. Measured, a 558px cover left five pixels
   between the description and the arrow, and a shorter window put the two on
   top of each other, because the copy descends at half the rate the arrow does.
   So the cover is a grid that measures itself: air above the lockup, the
   lockup, and a fixed band below it that the arrow sits in. The air and the
   band both scale with the window and neither can cross the other, the floor
   holds the shape on a short screen, and the ceiling stops an appendage from
   taking three quarters of a tall one.

   THE REASON IS NOT THAT THE MOTIF WAS BAD. Sources is a lettered companion
   rather than a numbered chapter, and a reader arrives at it from inside
   another chapter's argument to look something up. The numbered rooms announce
   themselves because a reader is entering them; an appendage should open in the
   archive's plain voice and get out of the way, which is what A About has
   always done. `chapter-field.css` carries the same rule for the field.
   =========================================================================== */
.chapter-hero.sources-cover{
  /* A column rather than a grid, because the lockup's own offset is a
     percentage and a percentage margin on a grid item resolves against its
     track rather than against the room, which moved the title a fifth of the
     cover to the right the first time this was written. */
  position:relative;display:flex;flex-direction:column;justify-content:flex-end;align-items:flex-start;
  min-height:min(62svh,560px);
  padding:clamp(110px,16vh,200px) 0 clamp(104px,12vh,136px);
  overflow:hidden;isolation:isolate;
  background:var(--mhc-ground);color:var(--mhc-on-paper);
}
.sources-cover::before,.sources-cover::after{content:none}
.sources-cover-copy{position:relative;z-index:1;margin-left:13%;width:50%;display:flex;flex-direction:column;align-items:flex-start}
.sources-cover-heading{position:relative;width:fit-content;max-width:100%}
.sources-cover-number{position:absolute;right:calc(100% + 16px);top:8px;margin:0;color:var(--mhc-chapter-sources-ink);font:500 12px/1.2 'Geist Mono',monospace;letter-spacing:.02em}
.sources-cover-copy h1{font:400 clamp(84px,10.5vw,148px)/.94 Helvetica,'Helvetica Neue',Arial,sans-serif;letter-spacing:-.055em;margin:0;max-width:none}
.sources-cover-description{max-width:29ch;margin-top:24px;font:400 20px/1.5 Helvetica,'Helvetica Neue',Arial,sans-serif;letter-spacing:-.025em;color:var(--mhc-on-paper-3)}
.sources-continue{position:absolute;z-index:2;left:50%;bottom:22px;transform:translateX(-50%);width:48px;height:48px;display:grid;place-items:center;text-decoration:none;color:var(--mhc-on-paper-3)}
.sources-continue svg{width:22px;height:22px;fill:none;stroke:currentColor;stroke-width:1.2}
.sources-continue:hover{color:var(--mhc-chapter-sources-ink)}
.sources-cover :focus-visible{outline:2px solid var(--mhc-chapter-sources-ink);outline-offset:4px}
@media(max-width:759px){
  .chapter-hero.sources-cover{min-height:min(56svh,450px);padding:clamp(84px,13vh,132px) 0 clamp(88px,11vh,112px)}
  .sources-cover-copy{margin-left:max(88px,13%);width:calc(100% - 110px)}
  .sources-cover-copy h1{font-size:min(84px,calc((100vw - 110px)/3.65))}
  .sources-cover-number{right:calc(100% + 10px);top:4px;font-size:10px}
  .sources-cover-description{max-width:27ch;font-size:18px}
}
@media print{
  .chapter-hero.sources-cover{min-height:0;padding:48px 0;break-after:page}
  .sources-cover-copy{width:auto}
  .sources-continue{display:none}
}

body>.site-shell>.chapter-hero.sources-cover{
  box-sizing:border-box;width:calc(100% + var(--elastic-content-left));
  margin-left:calc(-1 * var(--elastic-content-left));padding:0;
}
@media print{body>.site-shell>.chapter-hero.sources-cover{width:auto;margin-left:0}}