:root {
  --sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  --bg: #fff;
  --fg: #14171c;
  --muted: #6b7480;
  --link: #1f4fd8;
  --rule: #d9dde3;
  --rule-faint: #ecEFF3;
  --accent-bg: #f5f8ff;
  --lz-lecture: #3b5bdb;
  --lz-lab: #0d7a6f;
  --lz-disc: #7048b6;
  --lz-due: #b45309;
  --lz-exam: #b42318;
  --lz-reading: #52606d;
  --lz-holiday: #8b939c;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14171b; --fg: #e6e9ed; --muted: #939ba5;
    --link: #7ea6ff; --rule: #2b3138; --rule-faint: #21262c; --accent-bg: #1b2230;
    --lz-lecture: #5b78e8; --lz-lab: #17998b; --lz-disc: #9068d8;
    --lz-due: #d08324; --lz-exam: #d9534a; --lz-reading: #6b7684; --lz-holiday: #5c646d;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--bg); color: var(--fg);
  font: 14.5px/1.42 var(--sans);
  font-variant-numeric: tabular-nums;
}
a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; }
code { font: 0.86em/1 var(--mono); background: var(--rule-faint); padding: .1em .3em; border-radius: 3px; }

/* ------------------------------------------------------------------ layout */
.page {
  display: grid;
  grid-template-columns: 18.5rem minmax(0, 1fr);
  gap: 3rem;
  max-width: 70rem;
  margin: 0 auto;
  padding: 2.2rem 1.5rem 6rem;
}
.rail { position: sticky; top: 2.2rem; align-self: start; }
@media (max-width: 62rem) {
  .page { grid-template-columns: 1fr; gap: 2rem; padding: 1.2rem 1rem 4rem; }
  .rail { position: static; }
}

/* -------------------------------------------------------------- left rail */
.brand { margin-bottom: .9rem; }
.brand .home { display: block; color: var(--fg); }
.brand .course { font-size: 1.5rem; font-weight: 700; letter-spacing: -.015em; line-height: 1.1; }
.brand .term { color: var(--muted); font-size: .82rem; font-weight: 600;
               text-transform: uppercase; letter-spacing: .07em; margin-top: .1rem; }
.brand .coursetitle { font-size: .88rem; color: var(--fg); margin-top: .35rem; }
.intro { font-size: .87rem; color: var(--muted); margin-bottom: 1.3rem; }
.doodle { margin-bottom: 1.3rem; }
.doodle img { display: block; width: 100%; height: auto; }

.rail-sec { margin-bottom: 1.25rem; }
.rail-sec h3 {
  font-size: .68rem; font-weight: 700; text-transform: uppercase; letter-spacing: .1em;
  color: var(--muted); margin: 0 0 .3rem; padding-bottom: .22rem;
  border-bottom: 1px solid var(--rule);
}
ul.links, ul.staff { list-style: none; margin: 0; padding: 0; }
ul.links li { padding: .13rem 0; font-size: .9rem; }
ul.staff li { padding: .28rem 0; font-size: .9rem; line-height: 1.3; }
.sub { color: var(--muted); font-size: .78rem; }
.hours { display: block; color: var(--muted); font-size: .78rem; }
a.email { display: block; font-size: .78rem; }

/* Collapsible Staff section. The <summary> is styled to match .rail-sec h3
   so it reads as the section header; clicking it toggles the whole list. */
.rail-collapse > summary {
  list-style: none; cursor: pointer; outline: none;
  font-size: .68rem; font-weight: 700; text-transform: uppercase; letter-spacing: .1em;
  color: var(--muted); margin: 0 0 .3rem; padding-bottom: .22rem;
  border-bottom: 1px solid var(--rule);
}
.rail-collapse > summary::-webkit-details-marker { display: none; }
.rail-collapse > summary::after { content: "\25B8"; float: right; font-size: .8rem; }
.rail-collapse[open] > summary::after { content: "\25BE"; }

/* --------------------------------------------------------------- calendar */
.week { margin-bottom: 1.5rem; }
.week-label {
  font-size: .68rem; font-weight: 700; text-transform: uppercase; letter-spacing: .1em;
  color: var(--muted); margin: 0 0 .25rem; padding-bottom: .22rem;
  border-bottom: 1px solid var(--rule);
}
.week-label a { color: inherit; }
.week.current .week-label { color: var(--lz-lecture); }
.week.current { background: var(--accent-bg); border-radius: 5px;
                padding: .35rem .6rem .1rem; margin-left: -.6rem; margin-right: -.6rem; }

/* The week is one grid and rows are `display: contents`, so the three
   tracks line up across every row. The due track is content-sized and the
   1fr before it eats the slack, so the track's RIGHT edge is the grid's
   right edge in every week; the due lane is right-aligned and puts its
   lozenge last, so that lozenge is flush right no matter the text width. */
.rows { display: grid; grid-template-columns: 6.2rem minmax(0, 1fr) auto; }
.row { display: contents; }
.row > * { border-bottom: 1px solid var(--rule-faint); padding: .24rem 0; }
.rows > .row:last-child > * { border-bottom: 0; }
.when { color: var(--muted); font-size: .8rem; white-space: nowrap; padding-right: .9rem; }
.what { padding-right: .9rem; }
.due { text-align: right; }
/* .lz trails the text here, so its gap belongs on the left; a margin-right
   would push it off the flush-right edge. */
.due .lz { margin-right: 0; margin-left: .22em; }
.entry { padding: .08rem 0; }
.entry > a { font-weight: 500; }
.lz {
  display: inline-block; font-size: 10.5px; font-weight: 700; line-height: 1.65;
  text-transform: uppercase; letter-spacing: .045em;
  padding: 0 .45em; border-radius: 3px; margin-right: .18em;
  color: #fff; background: var(--lz-reading); white-space: nowrap; vertical-align: 1px;
}
.lz-lecture { background: var(--lz-lecture); }
.lz-lab     { background: var(--lz-lab); }
.lz-disc    { background: var(--lz-disc); }
.lz-due     { background: var(--lz-due); }
.lz-exam    { background: var(--lz-exam); }
.lz-reading { background: var(--lz-reading); }
.lz-holiday { background: var(--lz-holiday); }
.lz-who {
  background: transparent; color: var(--muted);
  box-shadow: inset 0 0 0 1px var(--rule);
}

.xtra { font-size: .78rem; color: var(--muted); margin-left: .15em; }
.xtra::before { content: "("; }
.xtra::after  { content: ")"; }
.reading { font-size: .78rem; color: var(--muted); margin-left: .3em; white-space: nowrap; }
.reading::before { content: "· "; }
.note { font-size: .82rem; color: var(--muted); margin-top: .02rem; }
@media (max-width: 62rem) {
  .rows { grid-template-columns: 5.6rem minmax(0, 1fr); }
  .due { grid-column: 2; text-align: left; }
}

/* ---------------------------------------------------------- office-hours page */
.gcal-embed { width: 100%; overflow: hidden; }
.gcal-embed iframe { width: 100%; min-height: 600px; display: block; }

/* Collapsible info panel used in the main column (e.g. help-hours writeup
   on the calendar page). Larger than the rail's .rail-collapse. */
.info-collapse {
  border: 1px solid var(--rule);
  border-radius: 6px;
  margin: 0 0 1.5rem;
  background: var(--bg);
}
.info-collapse > summary {
  list-style: none; cursor: pointer; outline: none;
  padding: .65rem .9rem;
  font-size: 1rem; font-weight: 600;
}
.info-collapse > summary::-webkit-details-marker { display: none; }
.info-collapse > summary::after {
  content: "\25B8"; float: right; color: var(--muted); font-size: .9rem;
}
.info-collapse[open] > summary { border-bottom: 1px solid var(--rule); }
.info-collapse[open] > summary::after { content: "\25BE"; }
.info-body { padding: .9rem; }
.info-body > *:first-child { margin-top: 0; }
.info-body > *:last-child { margin-bottom: 0; }
.info-body p { margin: 0 0 .75rem; }
.info-body ul { margin: 0 0 .75rem; padding-left: 1.25rem; }
.info-body img { max-width: 100%; height: auto; display: block; margin: .5rem 0 0; border: 1px solid var(--rule-faint); border-radius: 4px; }

/* ---------------------------------------------------------- assignments table */
.assign-table {
  width: 100%;
  border-collapse: collapse;
  table-layout: fixed;
  margin-top: 1rem;
}
.assign-table th,
.assign-table td {
  border: 1px solid var(--rule);
  padding: .65rem 1rem;
  text-align: left;
  vertical-align: middle;
  word-break: break-word;
}
.assign-table th {
  background: var(--accent-bg);
  font-size: .78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .07em;
  color: var(--muted);
}
.assign-table td {
  font-size: .9rem;
}
.assign-table tbody tr:hover td {
  background: var(--rule-faint);
}
@media (max-width: 40rem) {
  .assign-table { table-layout: auto; }
}