/* QuietDisk — classroom lesson-plan. Do not reuse on other products. */
:root {
  --board: #16332b;
  --chalk: #f3efe2;
  --mustard: #d4a017;
  --ink: #12241f;
  --muted: #5d6b5f;
  --paper: #efe8d4;
  --line: #c9bfa4;
  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
  --sans: "Avenir Next", "Gill Sans", "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--chalk);
  color: var(--ink);
  font-family: var(--serif);
  line-height: 1.6;
}

a { color: inherit; }
img { max-width: 100%; display: block; }

.lesson {
  width: min(1080px, calc(100% - 40px));
  margin: 0 auto;
}

.rule {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 28px 0 18px;
  border-bottom: 1px solid var(--line);
  font-family: var(--sans);
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}
.rule a { text-decoration: none; }
.rule .mark { color: var(--mustard); font-weight: 700; }

.board {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 48px;
  padding: 56px 0 40px;
  align-items: center;
}
.board h1 {
  font-size: clamp(2.4rem, 5vw, 4.1rem);
  line-height: 1.05;
  margin: 0 0 18px;
  font-weight: 500;
}
.kicker {
  font-family: var(--sans);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  font-size: 12px;
  color: var(--mustard);
  margin: 0 0 12px;
}
.lede {
  font-size: 1.15rem;
  color: var(--muted);
  margin: 0 0 24px;
}
.cta {
  display: inline-block;
  background: var(--board);
  color: var(--chalk);
  text-decoration: none;
  padding: 14px 22px;
  border-radius: 999px;
  font-family: var(--sans);
  font-size: 14px;
  letter-spacing: 0.04em;
}
.ghost {
  display: inline-block;
  margin-left: 16px;
  font-family: var(--sans);
  font-size: 14px;
}
.photo {
  background: var(--board);
  padding: 14px;
}
.photo img { width: 100%; }

.minutes {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  padding: 8px 0 48px;
}
.minutes div {
  border-top: 3px solid var(--board);
  padding-top: 12px;
}
.minutes b { display: block; font-size: 1.4rem; }

.period {
  background: var(--board);
  color: var(--chalk);
  padding: 64px 8vw;
  margin: 0 calc(50% - 50vw);
}
.period-inner {
  width: min(1080px, calc(100% - 0px));
  margin: 0 auto;
}
.period h2 {
  font-size: clamp(1.8rem, 3vw, 2.6rem);
  font-weight: 500;
  margin: 0 0 28px;
}
.rows { display: grid; gap: 22px; }
.row {
  display: grid;
  grid-template-columns: 90px 1fr;
  gap: 20px;
  border-top: 1px solid rgba(243, 239, 226, 0.18);
  padding-top: 16px;
}
.bell {
  font-family: var(--sans);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  font-size: 12px;
  color: var(--mustard);
}

.side {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  padding: 64px 0;
  align-items: center;
}
.side h2 { font-size: 2rem; font-weight: 500; margin: 0 0 12px; }

.card {
  background: var(--paper);
  border: 1px solid var(--line);
  padding: 36px;
  margin-bottom: 72px;
}
.card h2 { margin-top: 0; font-weight: 500; }
form { display: grid; gap: 12px; max-width: 420px; }
input {
  border: 1px solid var(--line);
  background: #fff;
  padding: 12px 14px;
  font: inherit;
}
button {
  background: var(--board);
  color: var(--chalk);
  border: 0;
  padding: 14px 18px;
  font-family: var(--sans);
  cursor: pointer;
}
.fine { font-size: 13px; color: var(--muted); }
.ok { color: #1c5a3a; }
.err { color: #8a2a1a; }

footer {
  padding: 0 0 48px;
  font-size: 13px;
  color: var(--muted);
}

@media (max-width: 800px) {
  .board, .side, .minutes, .row { grid-template-columns: 1fr; }
  .ghost { display: block; margin: 16px 0 0; }
}