/* CYS401 past papers: interactive replicas of the printed exam sheets.
   Shared by docs/academics/cybersecurity/cys401/exams/1[2-6]-*.html, which
   are generated by scripts/build_cys401_past_papers.py. */

:root {
  --desk: #e7eaee;
  --paper: #ffffff;
  --ink: #141414;
  --ink-2: #4a4f57;
  --rule: #1f1f1f;
  --line: #c3c9d1;
  --soft: #f3f5f8;
  --accent: hsl(212 72% 38%);
  --accent-soft: hsl(212 72% 45% / 0.1);
  --good: #17703f;
  --good-bg: #e6f5ec;
  --bad: #b3261e;
  --bad-bg: #fcebea;
  --half: #8a5a00;
  --half-bg: #fff4dc;
  --pen: #1d3fb0;
  --logo-bg: #2c2c2c;
  --logo-ink: #f2f2f2;
  --shadow: 0 1px 2px rgba(20, 25, 35, 0.08), 0 10px 30px rgba(20, 25, 35, 0.1);
  --serif: "Tinos", "Times New Roman", Times, serif;
  --sans: "Inter", system-ui, -apple-system, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, monospace;
  color-scheme: light;
}

html[data-theme="dark"] {
  --desk: #0b0e12;
  --paper: #161b21;
  --ink: #e6ebf0;
  --ink-2: #a3aebb;
  --rule: #8d99a6;
  --line: #36404b;
  --soft: #1d242c;
  --accent: hsl(212 85% 70%);
  --accent-soft: hsl(212 85% 65% / 0.14);
  --good: #6fd29a;
  --good-bg: #10261a;
  --bad: #ff8a80;
  --bad-bg: #2c1413;
  --half: #ffc96b;
  --half-bg: #2a2008;
  --pen: #8fb0ff;
  --logo-bg: #2a3038;
  --logo-ink: #e6ebf0;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 12px 32px rgba(0, 0, 0, 0.45);
  color-scheme: dark;
}

/* html-theme-sync.js injects overflow-x:hidden, which breaks the sticky bar */
html:not(#pp),
html:not(#pp) body {
  overflow-x: clip;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--desk);
  color: var(--ink);
  font: 15px/1.55 var(--sans);
}

/* ---------- toolbar ---------- */
.pp-bar {
  position: sticky;
  top: 0;
  z-index: 40;
  background: color-mix(in srgb, var(--desk) 86%, transparent);
  backdrop-filter: blur(10px) saturate(1.3);
  border-bottom: 1px solid var(--line);
}

.pp-bar-row {
  max-width: 1240px;
  margin: 0 auto;
  padding: 9px clamp(10px, 2.5vw, 28px);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 10px;
}

.pp-brand {
  font: 650 15px/1.2 var(--sans);
  color: var(--ink);
  text-decoration: none;
  white-space: nowrap;
}

.pp-chip {
  font: 600 11.5px/1 var(--mono);
  letter-spacing: 0.04em;
  padding: 6px 9px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: var(--paper);
  color: var(--ink-2);
  white-space: nowrap;
}

.pp-chip.term {
  color: var(--accent);
  border-color: color-mix(in srgb, var(--accent) 45%, transparent);
  background: var(--accent-soft);
}

.pp-score {
  font: 650 13.5px/1 var(--mono);
  white-space: nowrap;
}

.pp-actions {
  margin-left: auto;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  align-items: center;
}

.pp-btn {
  font: 600 12.5px/1 var(--sans);
  padding: 8px 11px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: var(--paper);
  color: var(--ink);
  cursor: pointer;
  white-space: nowrap;
}

.pp-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.pp-btn.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--paper);
}

.pp-btn.primary:hover {
  filter: brightness(1.08);
  color: var(--paper);
}

[data-page-search-host] {
  display: flex;
  min-width: 0;
}

/* ---------- desk + intro ---------- */
.desk {
  max-width: 1240px;
  margin: 0 auto;
  padding: 14px clamp(8px, 2.5vw, 28px) 40px;
}

.pp-intro {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 14px 18px;
  margin-bottom: 14px;
  color: var(--ink-2);
  font-size: 14.5px;
}

.pp-intro h1 {
  margin: 0 0 4px;
  font: 700 clamp(20px, 2.6vw, 26px)/1.2 var(--sans);
  color: var(--ink);
}

.pp-intro p {
  margin: 4px 0 0;
}

.pp-intro ul {
  margin: 6px 0 0;
  padding-left: 18px;
}

/* ---------- the sheet ---------- */
.sheet {
  background: var(--paper);
  color: var(--ink);
  box-shadow: var(--shadow);
  margin: 0 0 18px;
  padding: clamp(14px, 3.4vw, 46px) clamp(12px, 3.6vw, 52px)
    clamp(14px, 2.6vw, 30px);
  font: 16.5px/1.5 var(--serif);
}

.sheet.missing {
  background: transparent;
  box-shadow: none;
  border: 2px dashed var(--line);
  color: var(--ink-2);
  font: 15px/1.5 var(--sans);
  text-align: center;
  padding: 26px 18px;
}

.sheet.missing b {
  display: block;
  color: var(--ink);
  font-size: 16px;
  margin-bottom: 4px;
}

.psu-head {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  align-items: center;
  gap: 12px;
  margin-bottom: 14px;
}

.psu-en {
  text-align: center;
  line-height: 1.25;
}

.psu-en .uni {
  font-size: 1.12em;
}

.psu-en .col {
  font-size: 0.82em;
  font-weight: 700;
}

.psu-logo {
  background: var(--logo-bg);
  color: var(--logo-ink);
  padding: 6px 14px;
  text-align: center;
  line-height: 1.1;
  font-size: 0.78em;
  letter-spacing: 0.04em;
}

.psu-logo .big {
  display: block;
  font-size: 1.15em;
  font-weight: 700;
  letter-spacing: 0.06em;
}

.psu-ar {
  direction: rtl;
  text-align: center;
  line-height: 1.35;
  font-size: 0.95em;
}

.frame {
  border: 1.5px solid var(--rule);
  padding: clamp(10px, 2vw, 18px) clamp(10px, 2.2vw, 22px);
}

.frame + .frame {
  border-top: 0;
}

.qhead {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 4px 14px;
  font-weight: 700;
  margin: 2px 0 6px;
}

.qhead .marks {
  white-space: nowrap;
}

.got {
  display: inline-block;
  min-width: 2.6em;
  text-align: center;
  color: var(--bad);
  font-family: var(--sans);
  font-weight: 700;
}

.part {
  margin: 10px 0 4px;
  font-weight: 700;
}

.part.boxed {
  border: 1.5px solid var(--rule);
  padding: 4px 8px;
  margin: 0 0 8px;
}

.instr {
  margin: 2px 0 8px;
}

.instr ol,
.instr ul {
  margin: 4px 0 0;
}

/* ---------- questions ---------- */
.q {
  position: relative;
  margin: 8px 0 12px;
}

.q > .why {
  display: none;
}

.q-row {
  display: grid;
  grid-template-columns: 2em minmax(0, 1fr);
  gap: 0 4px;
}

.q-row > .n {
  text-align: right;
  padding-right: 4px;
}

.q-text {
  margin: 0;
}

.q-text b,
.q-text u {
  font-weight: 700;
}

.opts {
  margin: 4px 0 0;
  display: grid;
  gap: 1px;
}

.opts.two-col {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  border: 1px solid var(--rule);
  gap: 0;
}

.opts.two-col .opt {
  border: 1px solid var(--rule);
  padding: 4px 8px;
}

.opt {
  display: flex;
  align-items: baseline;
  gap: 6px;
  cursor: pointer;
  padding: 1px 4px;
  border-radius: 4px;
}

.opt input {
  position: absolute;
  opacity: 0;
  width: 1px;
  height: 1px;
  pointer-events: none;
}

.opt .ol,
.fig-opt .ol {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 1.7em;
  height: 1.55em;
  border: 1.6px solid transparent;
  border-radius: 999px;
}

.opt:hover .ol {
  border-color: var(--line);
}

.opt input:checked + .ol,
.fig-opt input:checked + .ol {
  border-color: var(--pen);
  color: var(--pen);
  font-weight: 700;
}

.opt input:focus-visible + .ol,
.fig-opt input:focus-visible + .ol {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.opt.is-right {
  background: var(--good-bg);
}

.opt.is-wrong {
  background: var(--bad-bg);
}

.fig-opts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  border: 1px solid var(--rule);
  margin-top: 6px;
}

.fig-opt {
  position: relative;
  border: 1px solid var(--rule);
  padding: 6px 8px 8px;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.fig-opt svg {
  width: 100%;
  height: auto;
  color: var(--ink);
}

.fig-opt.is-right {
  background: var(--good-bg);
}

.fig-opt.is-wrong {
  background: var(--bad-bg);
}

/* blanks, lines, ruled answer areas */
.blank,
.line-in {
  font: inherit;
  color: var(--pen);
  background: transparent;
  border: 0;
  border-bottom: 1.5px dashed var(--ink-2);
  padding: 0 4px;
  min-width: 8em;
  max-width: 100%;
}

select.blank {
  cursor: pointer;
}

select.blank option {
  color: var(--ink);
  background: var(--paper);
}

.line-in {
  min-width: 10em;
}

.line-in.wide {
  width: 100%;
}

.blank:focus,
.line-in:focus,
.ruled:focus {
  outline: 2px solid var(--accent-soft);
  border-bottom-color: var(--accent);
}

.ruled {
  display: block;
  width: 100%;
  font: inherit;
  color: var(--pen);
  background-color: transparent;
  background-image: repeating-linear-gradient(
    to bottom,
    transparent 0,
    transparent 29px,
    var(--line) 29px,
    var(--line) 30px
  );
  line-height: 30px;
  border: 0;
  padding: 0 4px;
  resize: vertical;
  min-height: 90px;
}

.ruled.short {
  min-height: 60px;
}

.ruled.cell {
  min-height: 60px;
  background-image: none;
  line-height: 1.45;
  padding: 2px;
}

.is-right.blank,
.is-right.line-in {
  border-bottom-color: var(--good);
  background: var(--good-bg);
}

.is-wrong.blank,
.is-wrong.line-in {
  border-bottom-color: var(--bad);
  background: var(--bad-bg);
}

/* paper tables */
.ptable {
  width: 100%;
  border-collapse: collapse;
  margin: 6px 0;
}

.ptable th,
.ptable td {
  border: 1px solid var(--rule);
  padding: 5px 7px;
  vertical-align: top;
  text-align: left;
}

.ptable th {
  font-weight: 700;
  text-align: center;
}

.ptable.center td {
  text-align: center;
}

.ptable td .line-in,
.ptable td .blank {
  width: 100%;
  min-width: 0;
}

.ptable.terms td {
  text-align: center;
  font-weight: 700;
}

/* html-theme-sync.js forces max-content tables; ours fit the sheet */
.sheet .sg-table-scroll > table.ptable {
  min-width: 0;
  width: 100%;
}

.sheet .sg-table-scroll {
  overflow-x: visible;
}

.sheet .sg-table-scroll > table:not(.ptable) {
  width: auto;
  min-width: 0;
}

.sheet .sg-table-scroll:has(> .tableau) {
  overflow-x: auto;
}

.sheet .sg-table-scroll > table.tableau {
  min-width: max-content;
}

.tableau {
  border-collapse: collapse;
  font: 600 11px/1 var(--mono);
  margin: 6px auto;
}

.tableau td,
.tableau th {
  border: 1px solid var(--line);
  width: 17px;
  height: 17px;
  text-align: center;
  padding: 0;
}

.tableau th {
  background: var(--soft);
}

.matrix5 {
  border-collapse: collapse;
  margin: 6px 0;
}

.matrix5 td {
  border: 1px solid var(--rule);
  width: 2.3em;
  height: 2.1em;
  text-align: center;
  padding: 0;
}

.matrix5 input {
  width: 100%;
  height: 2.1em;
  border: 0;
  text-align: center;
  font: 700 15px var(--serif);
  color: var(--pen);
  background: transparent;
  text-transform: uppercase;
}

.matrix5 td.is-right {
  background: var(--good-bg);
}

.matrix5 td.is-wrong {
  background: var(--bad-bg);
}

.alpha {
  border-collapse: collapse;
  font: 12px/1 var(--mono);
  margin: 6px 0;
}

.alpha td,
.alpha th {
  border: 1px solid var(--rule);
  padding: 4px 3px;
  text-align: center;
  min-width: 1.6em;
}

.mat {
  display: inline-grid;
  grid-auto-flow: column;
  gap: 2px 12px;
  padding: 2px 8px;
  border-left: 1.5px solid currentColor;
  border-right: 1.5px solid currentColor;
  border-radius: 6px;
  vertical-align: middle;
  font-family: var(--mono);
  font-size: 0.92em;
}

.mat span {
  text-align: center;
}

/* figures */
.fig {
  margin: 8px 0;
  color: var(--ink);
}

.fig svg {
  display: block;
  max-width: 100%;
  height: auto;
  margin: 0 auto;
}

.fig .lbl {
  font: 12px var(--serif);
  fill: currentColor;
}

/* McCumber overlay: labels sit on the drawing when there is room */
.mc {
  container-type: inline-size;
  max-width: 760px;
  margin: 8px auto;
}

.mc-stage {
  position: relative;
}

.mc-stage svg {
  display: block;
  width: 100%;
  height: auto;
}

.mc-slot select {
  width: 100%;
  font: 14px var(--serif);
}

.mc-list-label {
  display: none;
}

@container (min-width: 600px) {
  .mc-slot {
    position: absolute;
    left: var(--x);
    top: var(--y);
    width: var(--w);
  }
}

@container (max-width: 599.98px) {
  .mc-stage svg {
    max-width: 360px;
    margin: 0 auto;
  }

  .mc-slots {
    display: grid;
    gap: 6px;
    margin-top: 8px;
  }

  .mc-list-label {
    display: block;
    font-weight: 700;
    margin-top: 6px;
  }
}

/* ---------- feedback ---------- */
.fb {
  display: none;
  margin: 6px 0 0;
  padding: 8px 11px;
  border-radius: 8px;
  font: 14px/1.5 var(--sans);
  border: 1px solid transparent;
}

.fb.show {
  display: block;
}

.fb.ok {
  background: var(--good-bg);
  border-color: color-mix(in srgb, var(--good) 35%, transparent);
}

.fb.no {
  background: var(--bad-bg);
  border-color: color-mix(in srgb, var(--bad) 35%, transparent);
}

.fb.part {
  background: var(--half-bg);
  border-color: color-mix(in srgb, var(--half) 35%, transparent);
}

.fb .verdict {
  font-weight: 700;
  margin-right: 4px;
}

.fb.ok .verdict {
  color: var(--good);
}

.fb.no .verdict {
  color: var(--bad);
}

.fb.part .verdict {
  color: var(--half);
}

.model {
  display: none;
  margin: 8px 0 0;
  padding: 9px 12px;
  border: 1.5px dashed var(--accent);
  border-radius: 8px;
  background: var(--accent-soft);
  font: 14px/1.55 var(--sans);
}

.model.show {
  display: block;
}

.model > .tag {
  display: block;
  font: 650 11px/1 var(--mono);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 5px;
}

.model p,
.model ul,
.model ol,
.model table {
  margin: 4px 0 0;
}

.model ul,
.model ol {
  padding-left: 18px;
}

.model pre,
.fb pre {
  font: 12.5px/1.55 var(--mono);
  white-space: pre-wrap;
  margin: 6px 0 0;
}

.q-tools {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  margin-top: 6px;
  font-family: var(--sans);
}

.q-tools .pp-btn {
  padding: 6px 9px;
  font-size: 12px;
}

.selfmark {
  display: none;
  align-items: center;
  gap: 4px;
  flex-wrap: wrap;
  font: 12.5px var(--sans);
  color: var(--ink-2);
}

.selfmark.show {
  display: inline-flex;
}

.selfmark button {
  font: 600 12px/1 var(--mono);
  padding: 6px 8px;
  border-radius: 6px;
  border: 1px solid var(--line);
  background: var(--paper);
  color: var(--ink);
  cursor: pointer;
}

.selfmark button[aria-pressed="true"] {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--paper);
}

.page-foot {
  text-align: right;
  font-weight: 700;
  font-size: 1.15em;
  margin-top: 14px;
}

.doc-pageno {
  text-align: right;
  font-size: 0.85em;
}

.goodluck {
  text-align: center;
  font-weight: 700;
  margin: 18px 0 0;
}

/* Word-document style paper (Sem 181) */
.sheet.doc {
  font:
    15.5px/1.45 "Inter",
    "Calibri",
    Arial,
    sans-serif;
}

.doc-head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 18px;
  align-items: center;
  margin-bottom: 18px;
}

.doc-logo {
  width: 92px;
  height: 88px;
  background: #1f4f8c;
  color: #fff;
  display: grid;
  place-items: center;
  text-align: center;
  font: 700 10px/1.2 var(--sans);
  padding: 6px;
}

.doc-title {
  text-align: center;
  font-size: 1.4em;
  font-weight: 700;
  text-decoration: underline;
}

.doc-info {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px 24px;
  font-weight: 700;
  font-size: 1.08em;
}

.doc-info u {
  font-weight: 700;
}

.doc-h {
  font-weight: 700;
  text-decoration: underline;
  font-size: 1.15em;
  margin: 18px 0 2px;
}

.doc-sub {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 4px 14px;
  font-weight: 700;
  font-size: 1.12em;
  margin: 14px 0 6px;
}

.answer-grid td.mirror {
  font: 700 15px var(--mono);
  color: var(--pen);
  text-align: center;
  min-width: 3em;
}

/* quiz (232) layout */
.quiz-top {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 4px 12px;
  font-size: 0.95em;
}

.quiz-title {
  text-align: center;
  font-weight: 700;
  font-size: 1.15em;
  line-height: 1.35;
  margin: 12px 0 4px;
}

.quiz-title u {
  font-weight: 700;
}

.quiz-meta {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: end;
  gap: 12px;
}

.marks-box {
  border: 1.5px solid var(--rule);
  text-align: center;
  min-width: 96px;
}

.marks-box > div {
  padding: 3px 8px;
}

.marks-box > div + div {
  border-top: 1.5px solid var(--rule);
  font-family: var(--sans);
  font-weight: 700;
}

.end-line {
  text-align: center;
  letter-spacing: 0.06em;
  margin-top: 16px;
}

.dd-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px 18px;
}

.answer-box {
  border: 1.5px solid var(--rule);
  padding: 6px 10px;
}

.answer-box > .lab {
  font-weight: 700;
}

@media (max-width: 640px) {
  /* keep the paper's frames, but trim the nested gutters on phones */
  .desk {
    padding-left: 4px;
    padding-right: 4px;
  }

  .sheet {
    font-size: 15.5px;
    padding: 12px 6px 12px;
  }

  .frame {
    padding: 8px 6px;
  }

  .q-row {
    grid-template-columns: 1.6em minmax(0, 1fr);
  }

  .psu-head {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .psu-ar,
  .psu-en {
    font-size: 0.9em;
  }

  .opts.two-col,
  .fig-opts,
  .dd-grid,
  .doc-info {
    grid-template-columns: 1fr;
  }

  .doc-head {
    grid-template-columns: 1fr;
    justify-items: center;
  }

  .quiz-meta {
    grid-template-columns: 1fr;
  }

  [data-page-search-host],
  .pp-brand,
  .pp-btn .long {
    display: none;
  }

  /* two short rows: term + score, then the buttons */
  .pp-bar-row {
    padding-top: 7px;
    padding-bottom: 7px;
  }

  .pp-actions {
    margin-left: 0;
    width: 100%;
    flex-wrap: nowrap;
  }

  .pp-btn {
    padding: 7px 9px;
  }

  #pp-reveal {
    font-size: 0;
  }

  #pp-reveal::after {
    content: attr(data-short);
    font-size: 12.5px;
  }

  /* wide answer tables stack into labelled rows */
  .ptable.stack thead {
    display: none;
  }

  .ptable.stack,
  .ptable.stack tbody,
  .ptable.stack tr,
  .ptable.stack td {
    display: block;
    width: 100%;
  }

  .ptable.stack tr {
    border: 1px solid var(--rule);
    margin-bottom: 8px;
  }

  .ptable.stack td {
    border: 0;
    border-bottom: 1px solid var(--line);
  }

  .ptable.stack td[data-label]::before {
    content: attr(data-label);
    display: block;
    font: 650 10.5px/1.3 var(--mono);
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--ink-2);
    margin-bottom: 2px;
  }
}

@media print {
  .pp-bar,
  .q-tools,
  .pp-intro {
    display: none;
  }

  body {
    background: #fff;
  }

  .sheet {
    box-shadow: none;
    break-after: page;
  }
}