/* CIS400/600 — information-flow challenge app.
   Palette follows the course identity: Syracuse Orange + Navy, cyan signal. */

:root {
  --orange: #f76900;
  --orange-deep: #c25200;
  --navy: #000e54;
  --navy-soft: #1a277a;
  --signal: #0aa6b7;
  --signal-deep: #077784;
  --ink: #1a1a1a;
  --text: #26304a;
  --muted: #6b7a99;
  --page: #ffffff;
  --page-soft: #fbf9f4;
  --rule: #e6e0d1;
  --code-bg: #fdf6e3;
  --good: #4b8b3b;
  --good-bg: #eef7ea;
  --danger: #b7410e;
  --danger-bg: #fbeded;
  --mono: "SFMono-Regular", "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  background: var(--page-soft);
  color: var(--text);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.55;
}

code, pre, .mono { font-family: var(--mono); }

/* ------------------------------------------------------------------ header */

header.top {
  background: var(--navy);
  color: #fff;
  padding: 1.1rem 1.5rem 0;
  border-bottom: 4px solid var(--orange);
}

.top-inner {
  max-width: 1400px;
  margin: 0 auto;
  display: flex;
  align-items: flex-start;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.top h1 {
  margin: 0;
  font-size: 1.32rem;
  letter-spacing: 0.01em;
  font-weight: 700;
}

.top .course {
  color: var(--orange);
  font-weight: 700;
  font-size: 0.8rem;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  display: block;
  margin-bottom: 0.15rem;
}

.top p.sub {
  margin: 0.3rem 0 0;
  color: #c3cbe6;
  font-size: 0.9rem;
  max-width: 62ch;
}

.scorebox {
  margin-left: auto;
  text-align: right;
  font-size: 0.82rem;
  color: #c3cbe6;
  white-space: nowrap;
}

.scorebox strong { color: #fff; font-size: 1.35rem; display: block; line-height: 1.1; }

.scorebox button {
  margin-top: 0.35rem;
  background: transparent;
  border: 1px solid #4b5a92;
  color: #c3cbe6;
  border-radius: 5px;
  padding: 0.12rem 0.5rem;
  font-size: 0.75rem;
  cursor: pointer;
}
.scorebox button:hover { border-color: var(--orange); color: #fff; }

/* modes */

nav.modes {
  max-width: 1400px;
  margin: 0.9rem auto 0;
  display: flex;
  gap: 0.4rem;
  flex-wrap: wrap;
}

nav.modes button {
  background: transparent;
  border: none;
  border-bottom: 3px solid transparent;
  color: #9fb0d8;
  font-family: inherit;
  font-size: 0.95rem;
  font-weight: 600;
  padding: 0.5rem 0.9rem;
  cursor: pointer;
}
nav.modes button:hover { color: #fff; }
nav.modes button[aria-selected="true"] {
  color: #fff;
  border-bottom-color: var(--orange);
}
nav.modes .num {
  display: inline-block;
  font-size: 0.72rem;
  color: var(--signal);
  margin-left: 0.3rem;
}

/* ------------------------------------------------------------------- shell */

main {
  max-width: 1400px;
  margin: 0 auto;
  padding: 1.2rem 1.5rem 4rem;
}

.mode-intro {
  border-left: 4px solid var(--orange);
  background: var(--page);
  padding: 0.8rem 1.1rem;
  border-radius: 0 7px 7px 0;
  margin-bottom: 1rem;
}
.mode-intro h2 {
  margin: 0 0 0.15rem;
  font-size: 1.05rem;
  color: var(--navy);
}
.mode-intro .tagline {
  color: var(--orange-deep);
  font-weight: 600;
  font-size: 0.86rem;
}
.mode-intro p { margin: 0.4rem 0 0; font-size: 0.92rem; max-width: 90ch; }

.chal-nav { display: flex; gap: 0.45rem; margin-bottom: 1rem; flex-wrap: wrap; }
.chal-nav button {
  background: var(--page);
  border: 1px solid var(--rule);
  border-radius: 999px;
  padding: 0.28rem 0.85rem;
  font-family: inherit;
  font-size: 0.85rem;
  color: var(--text);
  cursor: pointer;
}
.chal-nav button:hover { border-color: var(--orange); }
.chal-nav button[aria-current="true"] {
  background: var(--navy);
  border-color: var(--navy);
  color: #fff;
  font-weight: 600;
}
.chal-nav .mark { margin-left: 0.35rem; font-weight: 700; }
.chal-nav .mark.right { color: var(--good); }
.chal-nav .mark.wrong { color: var(--orange); }
.chal-nav button[aria-current="true"] .mark.right { color: #8fd07a; }
.chal-nav button[aria-current="true"] .mark.wrong { color: #ffb27a; }

.grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 1.1rem;
  align-items: start;
}
@media (max-width: 1050px) { .grid { grid-template-columns: minmax(0, 1fr); } }

.card {
  background: var(--page);
  border: 1px solid var(--rule);
  border-radius: 8px;
  padding: 1rem 1.15rem;
  margin-bottom: 1.1rem;
}

.card h3 {
  margin: 0 0 0.5rem;
  font-size: 1.02rem;
  color: var(--navy);
}

.card h3 .idtag {
  font-family: var(--mono);
  font-size: 0.72rem;
  color: #fff;
  background: var(--signal-deep);
  border-radius: 4px;
  padding: 0.08rem 0.4rem;
  margin-right: 0.5rem;
  vertical-align: 0.12em;
}

.threat {
  font-size: 0.9rem;
  background: var(--page-soft);
  border-left: 3px solid var(--signal);
  padding: 0.5rem 0.75rem;
  border-radius: 0 5px 5px 0;
  margin-bottom: 0.8rem;
}
.threat b { color: var(--signal-deep); }

/* ---------------------------------------------------------------- program */

.labels {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  margin-bottom: 0.6rem;
  font-size: 0.8rem;
}
.lab {
  font-family: var(--mono);
  border-radius: 4px;
  padding: 0.1rem 0.45rem;
  border: 1px solid;
}
.lab.H { background: var(--danger-bg); border-color: #e0b4a6; color: #7f1d1d; }
.lab.L { background: var(--good-bg); border-color: #b9d7ae; color: #21501a; }
.lab .l { opacity: 0.7; }

pre.code {
  background: var(--code-bg);
  border: 1px solid var(--rule);
  border-radius: 6px;
  margin: 0;
  padding: 0.7rem 0.4rem 0.7rem 0;
  overflow-x: auto;
  font-size: 0.855rem;
  line-height: 1.62;
  tab-size: 2;
}
pre.code .ln {
  display: grid;
  grid-template-columns: 2.5rem 1.15rem 1fr;
  align-items: baseline;
}
pre.code .n {
  color: #a89b7a;
  text-align: right;
  padding-right: 0.6rem;
  user-select: none;
  font-size: 0.78em;
}
pre.code .gut { text-align: center; font-size: 0.8em; user-select: none; }
pre.code .ln.bad { background: #fbeaea; }
pre.code .ln.bad .gut { color: var(--danger); font-weight: 700; }
pre.code .ln.ok .gut { color: #9ec48f; }
pre.code .ln.pcraise { background: #fdf1e3; }
pre.code .ln.pcraise .gut { color: var(--orange-deep); font-weight: 700; }
.kw { color: #859900; font-weight: 600; }
.num { color: #2aa198; }
.cm { color: #93a1a1; font-style: italic; }
.fn { color: #268bd2; }

.costnote {
  font-size: 0.78rem;
  color: var(--muted);
  margin-top: 0.55rem;
}
.costnote code { background: var(--code-bg); padding: 0 0.2em; border-radius: 3px; }

.lowctl {
  margin-top: 0.7rem;
  font-size: 0.86rem;
  background: var(--page-soft);
  border: 1px dashed var(--rule);
  border-radius: 6px;
  padding: 0.5rem 0.7rem;
}
.lowctl select {
  font-family: var(--mono);
  font-size: 0.9rem;
  padding: 0.15rem 0.3rem;
  margin-left: 0.4rem;
}

/* --------------------------------------------------------------- question */

.qprompt { font-size: 0.98rem; margin: 0 0 0.75rem; }

.opts { display: flex; flex-direction: column; gap: 0.4rem; }

.opt {
  display: flex;
  gap: 0.6rem;
  align-items: flex-start;
  border: 1px solid var(--rule);
  border-radius: 7px;
  padding: 0.5rem 0.7rem;
  cursor: pointer;
  background: var(--page);
  font-size: 0.92rem;
  text-align: left;
  font-family: inherit;
  color: var(--text);
  line-height: 1.45;
}
.opt:hover:not(:disabled) { border-color: var(--orange); background: #fffaf5; }
.opt .key {
  font-family: var(--mono);
  font-size: 0.78rem;
  border: 1px solid var(--rule);
  border-radius: 4px;
  padding: 0 0.35rem;
  color: var(--muted);
  flex: none;
  margin-top: 0.08rem;
}
.opt[aria-pressed="true"] { border-color: var(--navy); box-shadow: inset 0 0 0 1px var(--navy); }
.opt.correct { border-color: var(--good); background: var(--good-bg); }
.opt.correct .key { border-color: var(--good); color: var(--good); }
.opt.wrong { border-color: var(--danger); background: var(--danger-bg); }
.opt.wrong .key { border-color: var(--danger); color: var(--danger); }
.opt:disabled { cursor: default; }

.qactions { margin-top: 0.8rem; display: flex; gap: 0.5rem; align-items: center; }

button.primary {
  background: var(--orange);
  border: 1px solid var(--orange-deep);
  color: #fff;
  font-family: inherit;
  font-weight: 600;
  font-size: 0.9rem;
  border-radius: 6px;
  padding: 0.35rem 0.95rem;
  cursor: pointer;
}
button.primary:hover { background: var(--orange-deep); }
button.primary:disabled { opacity: 0.45; cursor: default; }

button.ghost {
  background: transparent;
  border: 1px solid var(--rule);
  color: var(--text);
  font-family: inherit;
  font-size: 0.85rem;
  border-radius: 6px;
  padding: 0.32rem 0.8rem;
  cursor: pointer;
}
button.ghost:hover { border-color: var(--navy); }

.verdict {
  margin-top: 0.85rem;
  padding: 0.55rem 0.8rem;
  border-radius: 6px;
  font-size: 0.92rem;
  font-weight: 600;
}
.verdict.right { background: var(--good-bg); color: #21501a; border: 1px solid #b9d7ae; }
.verdict.wrong { background: var(--danger-bg); color: #7f1d1d; border: 1px solid #e0b4a6; }

/* ----------------------------------------------------------------- reveal */

.tabs { display: flex; gap: 0.2rem; border-bottom: 2px solid var(--rule); margin-bottom: 0.85rem; flex-wrap: wrap; }
.tabs button {
  background: transparent;
  border: none;
  border-bottom: 3px solid transparent;
  margin-bottom: -2px;
  font-family: inherit;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--muted);
  padding: 0.35rem 0.7rem;
  cursor: pointer;
}
.tabs button:hover { color: var(--navy); }
.tabs button[aria-selected="true"] { color: var(--navy); border-bottom-color: var(--orange); }

.obsbar { display: flex; gap: 0.4rem; align-items: center; margin-bottom: 0.7rem; flex-wrap: wrap; font-size: 0.85rem; }
.obsbar .seg { display: flex; border: 1px solid var(--rule); border-radius: 6px; overflow: hidden; }
.obsbar .seg button {
  background: var(--page);
  border: none;
  border-right: 1px solid var(--rule);
  font-family: inherit;
  font-size: 0.84rem;
  padding: 0.25rem 0.75rem;
  cursor: pointer;
  color: var(--text);
}
.obsbar .seg button:last-child { border-right: none; }
.obsbar .seg button[aria-pressed="true"] { background: var(--navy); color: #fff; font-weight: 600; }
.obsdef { font-size: 0.8rem; color: var(--muted); }
.obsdef .mono { color: var(--navy-soft); }

table.runs { border-collapse: collapse; width: 100%; font-size: 0.83rem; }
table.runs th, table.runs td {
  border-bottom: 1px solid var(--rule);
  padding: 0.3rem 0.5rem;
  text-align: left;
  vertical-align: top;
}
table.runs th { color: var(--muted); font-weight: 600; font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.04em; }
table.runs td.mono, table.runs td .mono { font-family: var(--mono); }
table.runs tr.cls td { border-top: 2px solid var(--rule); }

.cbadge {
  display: inline-block;
  font-family: var(--mono);
  font-size: 0.72rem;
  font-weight: 700;
  border-radius: 4px;
  padding: 0.05rem 0.4rem;
  color: #fff;
}

.summary {
  font-size: 0.86rem;
  background: var(--page-soft);
  border: 1px solid var(--rule);
  border-radius: 6px;
  padding: 0.5rem 0.7rem;
  margin-bottom: 0.7rem;
}
.summary b { color: var(--navy); }

.stats { display: flex; gap: 0.7rem; flex-wrap: wrap; margin-bottom: 0.9rem; }
.stat {
  flex: 1 1 8rem;
  background: var(--page-soft);
  border: 1px solid var(--rule);
  border-radius: 7px;
  padding: 0.5rem 0.7rem;
}
.stat .v { font-size: 1.5rem; font-weight: 700; color: var(--navy); line-height: 1.15; font-family: var(--mono); }
.stat .v.hot { color: var(--danger); }
.stat .v.cool { color: var(--good); }
.stat .k { font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.045em; color: var(--muted); }

.bars { margin: 0.4rem 0 0.9rem; }
.bar { display: grid; grid-template-columns: 5rem 1fr 5.2rem; gap: 0.5rem; align-items: center; font-size: 0.83rem; margin-bottom: 0.3rem; }
.bar .track { background: #ece7da; border-radius: 4px; height: 0.85rem; overflow: hidden; }
.bar .fill { height: 100%; background: linear-gradient(90deg, var(--signal), var(--orange)); }
.bar .amt { font-family: var(--mono); font-size: 0.8rem; color: var(--navy); }
.bar .nm { font-weight: 600; color: var(--text); }

.formula {
  font-family: var(--mono);
  font-size: 0.82rem;
  background: var(--code-bg);
  border: 1px solid var(--rule);
  border-radius: 6px;
  padding: 0.5rem 0.7rem;
  margin: 0.5rem 0;
  overflow-x: auto;
  white-space: pre;
  color: #4a4436;
}

.checklist { font-size: 0.84rem; }
.checklist .c {
  display: grid;
  grid-template-columns: 2.2rem 1fr;
  gap: 0.5rem;
  border-bottom: 1px solid var(--rule);
  padding: 0.35rem 0.2rem;
}
.checklist .c .mark { font-weight: 700; text-align: right; font-family: var(--mono); }
.checklist .c.ok .mark { color: var(--good); }
.checklist .c.bad { background: var(--danger-bg); }
.checklist .c.bad .mark { color: var(--danger); }
.checklist .c.pc { background: #fdf1e3; }
.checklist .c.pc .mark { color: var(--orange-deep); }
.checklist .stmt { font-family: var(--mono); color: var(--navy); }
.checklist .why { font-family: var(--mono); font-size: 0.78rem; color: var(--muted); }
.checklist .lno { font-family: var(--mono); font-size: 0.75rem; color: #a89b7a; }

.banner {
  border-radius: 6px;
  padding: 0.5rem 0.8rem;
  font-size: 0.9rem;
  margin-bottom: 0.7rem;
  font-weight: 600;
}
.banner.accept { background: var(--good-bg); border: 1px solid #b9d7ae; color: #21501a; }
.banner.reject { background: var(--danger-bg); border: 1px solid #e0b4a6; color: #7f1d1d; }

.disc { font-size: 0.93rem; }
.disc p { margin: 0 0 0.7rem; max-width: 78ch; }
.disc p.teach {
  background: var(--page-soft);
  border-left: 3px solid var(--orange);
  padding: 0.45rem 0.7rem;
  border-radius: 0 5px 5px 0;
  font-size: 0.88rem;
}
.disc code { background: var(--code-bg); padding: 0 0.22em; border-radius: 3px; font-size: 0.92em; }

.fixbox {
  border: 1px solid var(--rule);
  border-left: 4px solid var(--good);
  border-radius: 0 7px 7px 0;
  background: var(--good-bg);
  padding: 0.6rem 0.8rem;
  margin-top: 0.9rem;
  font-size: 0.88rem;
}
.fixbox h4 { margin: 0 0 0.3rem; font-size: 0.92rem; color: #21501a; }

/* bench */

.bench textarea {
  width: 100%;
  font-family: var(--mono);
  font-size: 0.83rem;
  line-height: 1.55;
  border: 1px solid var(--rule);
  border-radius: 6px;
  background: var(--code-bg);
  padding: 0.6rem;
  min-height: 13rem;
  resize: vertical;
  color: var(--ink);
}
.bench .row { display: flex; gap: 0.5rem; align-items: center; margin: 0.5rem 0; flex-wrap: wrap; font-size: 0.85rem; }
.bench input[type="text"] {
  flex: 1 1 16rem;
  font-family: var(--mono);
  font-size: 0.83rem;
  border: 1px solid var(--rule);
  border-radius: 6px;
  padding: 0.3rem 0.5rem;
}
.bench .err {
  background: var(--danger-bg);
  border: 1px solid #e0b4a6;
  color: #7f1d1d;
  border-radius: 6px;
  padding: 0.45rem 0.7rem;
  font-family: var(--mono);
  font-size: 0.82rem;
}

svg.curve { width: 100%; height: auto; display: block; }

.footnote { font-size: 0.78rem; color: var(--muted); margin-top: 0.8rem; max-width: 82ch; }

details.more { margin-top: 0.6rem; font-size: 0.84rem; }
details.more summary { cursor: pointer; color: var(--signal-deep); font-weight: 600; }

.kbdhint { font-size: 0.76rem; color: var(--muted); margin-top: 0.9rem; text-align: center; }
kbd {
  font-family: var(--mono);
  font-size: 0.72rem;
  border: 1px solid var(--rule);
  border-bottom-width: 2px;
  border-radius: 4px;
  padding: 0 0.3rem;
  background: var(--page);
}