/* ENGE3940 activities. One column, system fonts, no libraries. */
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0 auto; padding: 24px 16px 72px; max-width: 680px;
  font-family: system-ui, -apple-system, "Segoe UI", Arial, sans-serif;
  font-size: 17px; line-height: 1.55; color: #333; background: #fff;
}
a { color: #1f4f5e; }
h1 { font-size: 28px; font-weight: 400; line-height: 1.2; margin: 6px 0 12px; }
h2 { font-size: 20px; font-weight: 400; margin: 36px 0 8px; }
p { margin: 0 0 12px; }
ul, ol { margin: 0 0 12px; padding-left: 22px; }
li { margin-bottom: 4px; }
.course { color: #6b6b6b; font-size: 15px; margin: 0; }
.small { color: #6b6b6b; font-size: 14px; }
.takeaway { color: #bf0000; }
.box { background: #ededed; padding: 12px 14px; margin: 0 0 12px; }
.box .label { display: block; font-size: 13px; font-weight: 700; color: #1f4f5e; margin-bottom: 4px; }
.box p:last-child { margin-bottom: 0; }
.hidden { display: none; }

/* questions */
.q { margin: 0 0 12px; }
.q label.opt { display: block; padding: 8px 10px; margin: 0 0 6px; border: 1px solid #bfbfbf; cursor: pointer; }
.q label.opt:hover { background: #f6f6f6; }
.q input[type="radio"] { margin-right: 8px; }
button {
  font: inherit; padding: 8px 16px; border: 1px solid #1f4f5e; background: #1f4f5e; color: #fff; cursor: pointer;
}
button:hover { background: #173c48; }
button:focus-visible, select:focus-visible, input:focus-visible, textarea:focus-visible { outline: 2px solid #bf0000; outline-offset: 2px; }
select, input[type="text"], textarea {
  font: inherit; width: 100%; padding: 8px; border: 1px solid #bfbfbf; background: #fff; color: #333;
}
textarea { min-height: 64px; }
.fb { padding: 10px 12px; margin: 10px 0 0; }
.fb.ok { background: #dce9e8; }
.fb.no { background: #f7dddd; }
.row { margin: 0 0 16px; }
.row .fb { margin-top: 6px; }
table { border-collapse: collapse; width: 100%; margin: 0 0 12px; }
td, th { border: 1px solid #bfbfbf; padding: 8px 10px; text-align: left; vertical-align: top; }
th { color: #1f4f5e; }
.list { list-style: none; padding: 0; }
.list li { border-top: 1px solid #bfbfbf; padding: 12px 0; margin: 0; }
.list li:last-child { border-bottom: 1px solid #bfbfbf; }
footer { margin-top: 48px; padding-top: 12px; border-top: 1px solid #bfbfbf; }

/* class mode */
#classbar { background: #ededed; padding: 8px 12px; margin: 0 0 16px; font-size: 15px; }
#classbar input { width: 5.5em; text-transform: uppercase; }
button.plain { background: #fff; color: #1f4f5e; padding: 4px 10px; }
button.plain:hover { background: #f6f6f6; }
.tap .part { display: block; width: 100%; text-align: left; background: #ededed; color: #333; border: 2px solid #ededed; margin: 0 0 6px; padding: 10px 12px; }
.tap .part:hover { background: #e4e4e4; }
.tap .part[aria-pressed="true"] { border-color: #1f4f5e; background: #dce9e8; }

/* class view (tutor's screen) */
.wide { max-width: 900px; }
.code { font-size: 64px; letter-spacing: 8px; line-height: 1.1; margin: 0 0 4px; color: #333; }
.result { margin: 0 0 28px; }
.result h2 { margin-top: 28px; }
.barrow { display: grid; grid-template-columns: minmax(120px, 2fr) 3fr 3em; gap: 10px; align-items: center; margin: 0 0 6px; }
.barrow .track { background: #ededed; height: 22px; }
.barrow .fill { background: #1f4f5e; height: 22px; }
.shade { font-size: 22px; line-height: 1.6; }
.shade span { padding: 2px 0; }
.shade sup { color: #6b6b6b; font-size: 13px; }