/* Junior Robotics Notes: lab-notebook sheet, indigo ink and coral pads. */
:root {
  --pcb-ink: #23265a;
  --pcb-pad: #ff7a5c;
  --pcb-hair: #c9cbe0;
  --pcb-page: #f7f7fb;
  --pcb-dim: #5a5d86;
  --pcb-pad-ink: #b8442a;
  --pcb-r: 4px;
  --pcb-sans: system-ui, sans-serif;
  --pcb-mono: ui-monospace, "Cascadia Mono", Menlo, monospace;
  --pcb-col: 44rem;
}

*,
*::before,
*::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

.pcb {
  margin: 0;
  background: var(--pcb-page);
  color: var(--pcb-ink);
  font: 1.0625rem/1.65 var(--pcb-sans);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.pcb a { color: var(--pcb-ink); text-decoration-color: var(--pcb-pad); text-underline-offset: 3px; }
.pcb a:hover { color: var(--pcb-pad-ink); }
.pcb a:focus-visible { outline: 2px dashed var(--pcb-pad); outline-offset: 2px; }

.pcb-skip { position: absolute; left: -999px; }
.pcb-skip:focus { left: 1rem; top: 1rem; background: #fff; padding: .4rem .7rem; }

/* masthead */
.pcb-mast {
  width: min(100% - 2rem, 62rem);
  margin: 0 auto;
  padding-top: 1.6rem;
  display: flex;
  flex-direction: column;
  gap: .15rem;
}
.pcb-mast__row { display: flex; align-items: center; gap: .6rem; }
.pcb-mark {
  font: .78rem/1 var(--pcb-mono);
  letter-spacing: .04em;
  text-decoration: none;
  color: var(--pcb-dim) !important;
}
.pcb-mast__pin {
  width: .55rem;
  height: .55rem;
  border-radius: 50%;
  background: var(--pcb-pad);
}
.pcb-title {
  margin: .35rem 0 0;
  font-size: clamp(1.7rem, 4vw, 2.4rem);
  font-weight: 850;
  letter-spacing: -.02em;
  line-height: 1.1;
}
.pcb-strap { margin: 0; color: var(--pcb-dim); font-size: .95rem; }

.pcb-trace {
  margin: .9rem 0 .5rem;
  height: 0;
  border-top: 2px dotted var(--pcb-hair);
  position: relative;
}
.pcb-trace::after {
  content: "";
  position: absolute;
  right: 0;
  top: -5px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--pcb-pad);
}
.pcb-trace--thin { border-top-width: 1px; }

.pcb-menu { display: flex; flex-wrap: wrap; gap: .3rem 1.1rem; font-size: .92rem; }
.pcb-menu__link { text-decoration: none; padding: .15rem 0; }
.pcb-menu__link[aria-current="page"] { box-shadow: inset 0 -2px var(--pcb-pad); }

/* sheet */
.pcb-sheet {
  flex: 1;
  width: min(100% - 2rem, 62rem);
  margin: 1.4rem auto 3rem;
  container-type: inline-size;
  container-name: sheet;
}
.pcb-sheet h1, .pcb-sheet h2, .pcb-sheet h3 { font-weight: 800; line-height: 1.2; }
.pcb-page__title, .pcb-intro__head { font-size: clamp(1.6rem, 3.4vw, 2.1rem); margin: 0 0 .6rem; }
.pcb-intro { max-width: var(--pcb-col); }
.pcb-lede { color: var(--pcb-dim); font-size: 1.08rem; margin-top: 0; }

.pcb-code {
  font: 600 .78rem/1 var(--pcb-mono);
  color: var(--pcb-pad-ink);
  border: 1px solid var(--pcb-hair);
  border-radius: var(--pcb-r);
  padding: .25rem .4rem;
  background: #fff;
  white-space: nowrap;
}

/* numbered index */
.pcb-shelf__head {
  font: 700 .8rem/1 var(--pcb-mono);
  text-transform: uppercase;
  letter-spacing: .12em;
  color: var(--pcb-dim);
  margin: 2.2rem 0 1rem;
}
.pcb-index { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 1.1rem; }
.pcb-index--two { flex-flow: row wrap; gap: 1.2rem 2.4rem; }
.pcb-index--two > .pcb-index__item { flex: 1 1 100%; }
@container sheet (min-width: 40rem) {
  .pcb-index--two > .pcb-index__item { flex-basis: calc(50% - 1.2rem); }
}
.pcb-index__item {
  display: flex;
  gap: .8rem;
  align-items: flex-start;
  padding-top: .9rem;
  border-top: 1px solid var(--pcb-hair);
}
.pcb-index__text { display: flex; flex-direction: column; gap: .2rem; }
.pcb-index__link { font-weight: 750; font-size: 1.08rem; }
.pcb-index__blurb { margin: 0; font-size: .95rem; }
.pcb-index__date { font: .74rem/1.4 var(--pcb-mono); color: var(--pcb-dim); }

.pcb-ways__list { display: flex; flex-wrap: wrap; gap: 1rem 2rem; margin: 0; }
.pcb-ways__list > div { flex: 1 1 14rem; }
.pcb-ways__list dt { font-weight: 750; }
.pcb-ways__list dd { margin: .1rem 0 0; color: var(--pcb-dim); font-size: .95rem; }

/* single note */
.pcb-note, .pcb-body { max-width: var(--pcb-col); }
.pcb-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .4rem .9rem;
  font: .8rem/1.4 var(--pcb-mono);
  margin: 0 0 .8rem;
}
.pcb-note__title { font-size: clamp(1.7rem, 3.6vw, 2.3rem); margin: 0 0 .5rem; letter-spacing: -.01em; }
.pcb-body h2 { font-size: 1.3rem; margin: 2rem 0 .5rem; }
.pcb-body h3 { font-size: 1.08rem; margin: 1.5rem 0 .4rem; }
.pcb-body li { margin-bottom: .35rem; }
.pcb-body code { font: .9em var(--pcb-mono); background: #ecedf6; padding: 0 .25em; border-radius: var(--pcb-r); }
.pcb-body pre {
  font: .85rem/1.5 var(--pcb-mono);
  background: var(--pcb-ink);
  color: var(--pcb-page);
  padding: .9rem 1rem;
  border-radius: var(--pcb-r);
  overflow-x: auto;
}
.pcb-body pre code { background: none; padding: 0; color: inherit; }

/* procedures: step numbers hang in the left margin */
.pcb-steps { list-style: none; counter-reset: pcbstep; padding-left: 0; margin: 1.2rem 0; }
.pcb-steps > li {
  counter-increment: pcbstep;
  position: relative;
  padding-left: 2.6rem;
  margin-bottom: .9rem;
}
.pcb-steps > li::before {
  content: counter(pcbstep, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: .05rem;
  font: 700 .8rem/1.7 var(--pcb-mono);
  color: var(--pcb-pad-ink);
  border-right: 2px solid var(--pcb-pad);
  padding-right: .45rem;
}
@container sheet (min-width: 56rem) {
  .pcb-steps > li { padding-left: 0; }
  .pcb-steps > li::before { left: -3.2rem; }
}

.pcb-diagram {
  margin: 1.6rem 0;
  padding: 1rem;
  border: 1px dashed var(--pcb-hair);
  border-radius: var(--pcb-r);
  background: #fff;
}
.pcb-diagram svg { display: block; width: 100%; height: auto; }
.pcb-diagram figcaption { font: .8rem/1.5 var(--pcb-mono); color: var(--pcb-dim); margin-top: .6rem; }

.pcb-callout {
  border-left: 3px solid var(--pcb-pad);
  padding: .4rem 0 .4rem 1rem;
  background: #fff;
}
.pcb-sources { font-size: .92rem; border-top: 1px dotted var(--pcb-hair); margin-top: 2rem; padding-top: .8rem; }

.pcb-near {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 1rem;
  margin-top: 2.5rem;
  padding-top: 1rem;
  border-top: 2px dotted var(--pcb-hair);
  font-size: .95rem;
}
.pcb-near__link { display: flex; gap: .5rem; align-items: baseline; text-decoration: none; }

/* footer */
.pcb-foot {
  width: min(100% - 2rem, 62rem);
  margin: 0 auto;
  padding-bottom: 2rem;
  font-size: .86rem;
  color: var(--pcb-dim);
}
.pcb-archline { max-width: var(--pcb-col); }
.pcb-foot__links { display: flex; flex-wrap: wrap; gap: .5rem; }