:root {
  --navy: #16324f;
  --teal: #2a7f7e;
  --paper: #fbfaf7;
  --ink: #1c1c1c;
  --muted: #5b5b5b;
  --line: #dfe3e6;
  --bio: #2a7f4f;
  --chem: #7f3f2a;
  --careers: #16324f;
  --teach: #5a3f7f;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "Georgia", "Iowan Old Style", serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.55;
}

header.site-header {
  background: var(--navy);
  color: white;
  padding: 1.75rem 1.5rem;
}

header.site-header h1 {
  margin: 0 0 0.25rem 0;
  font-size: 1.6rem;
  font-family: "Helvetica Neue", Arial, sans-serif;
  letter-spacing: 0.02em;
}

header.site-header p {
  margin: 0;
  color: #cfe0dc;
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.95rem;
}

nav.site-nav {
  background: var(--teal);
}

nav.site-nav a {
  color: white;
  text-decoration: none;
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.9rem;
  padding: 0.6rem 1.5rem;
  display: inline-block;
}

nav.site-nav a:hover { text-decoration: underline; }

main {
  max-width: 780px;
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem 1.5rem;
}

.book-nod {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.88rem;
  color: var(--muted);
  margin-bottom: 0.75rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--line);
}

.intro {
  color: var(--muted);
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.95rem;
  margin-bottom: 2rem;
}

.subject-block { margin-bottom: 2.5rem; }

.subject-block h2 {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 1.05rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  border-bottom: 2px solid var(--line);
  padding-bottom: 0.4rem;
}

.subject-block.biology h2 { color: var(--bio); border-color: var(--bio); }
.subject-block.chemistry h2 { color: var(--chem); border-color: var(--chem); }
.subject-block.careers h2 { color: var(--careers); border-color: var(--careers); }
.subject-block.teaching h2 { color: var(--teach); border-color: var(--teach); }

.section-note {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.9rem;
  color: var(--muted);
  margin-top: 0.4rem;
  margin-bottom: 1rem;
}

ol.topic-list {
  list-style: decimal;
  margin: 0;
  padding: 0 0 0 1.4rem;
  counter-reset: list-item;
}

ol.topic-list li {
  padding: 0.55rem 0;
  padding-left: 0.4rem;
  border-bottom: 1px solid var(--line);
  font-size: 1.05rem;
}

ol.topic-list li::marker {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--teal);
}

ol.topic-list li a {
  color: var(--ink);
  text-decoration: none;
}

ol.topic-list li a:hover { color: var(--teal); text-decoration: underline; }

ol.topic-list li .tag {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.72rem;
  color: var(--muted);
  display: block;
  margin-top: 0.15rem;
}

footer.site-footer {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.8rem;
  color: var(--muted);
  text-align: center;
  padding: 2rem 1rem 3rem 1rem;
}

/* ---- One-pager article styles ---- */

article.onepager {
  max-width: 720px;
  margin: 0 auto;
  padding: 2.5rem 1.75rem 4rem 1.75rem;
}

.back-link {
  display: inline-block;
  margin-bottom: 1.5rem;
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.85rem;
  color: var(--teal);
  text-decoration: none;
}

.back-link:hover { text-decoration: underline; }

article.onepager .eyebrow {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--muted);
  margin-bottom: 0.4rem;
}

article.onepager h1 {
  font-size: 1.9rem;
  margin: 0 0 0.5rem 0;
  line-height: 1.2;
}

article.onepager .meta {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.8rem;
  color: var(--muted);
  margin-bottom: 1.75rem;
  padding-bottom: 1.25rem;
  border-bottom: 1px solid var(--line);
}

article.onepager h2 {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 1.0rem;
  color: var(--teal);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-top: 2rem;
}

article.onepager p { font-size: 1.05rem; }

article.onepager .vocab {
  background: white;
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 1rem 1.25rem;
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.9rem;
}

article.onepager .vocab dt { font-weight: 700; margin-top: 0.5rem; }
article.onepager .vocab dt:first-child { margin-top: 0; }
article.onepager .vocab dd { margin: 0 0 0.4rem 0; color: var(--muted); }

article.onepager .check-understanding {
  background: #eef6f4;
  border-left: 4px solid var(--teal);
  padding: 1rem 1.25rem;
  font-size: 0.98rem;
}

article.onepager .check-understanding ol { margin: 0.5rem 0 0 1.1rem; padding: 0; }

article.onepager .sources {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.82rem;
  color: var(--muted);
}

/* ---- Modular teaching index (table + filter) ---- */

.index-search {
  width: 100%;
  max-width: 420px;
  padding: 0.55rem 0.75rem;
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.95rem;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: white;
  color: var(--ink);
}

.table-scroll {
  overflow-x: auto;
  margin: 1.5rem 0;
}

table.modular-index {
  border-collapse: collapse;
  width: 100%;
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.88rem;
  background: white;
}

table.modular-index th,
table.modular-index td {
  border: 1px solid var(--line);
  padding: 0.65rem 0.75rem;
  text-align: left;
  vertical-align: top;
}

table.modular-index th {
  background: var(--teach);
  color: white;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

table.modular-index td a { color: var(--teal); }

.part-tag {
  display: inline-block;
  font-size: 0.72rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.03em;
  margin-bottom: 0.2rem;
}

/* ---- Teacher protocol boxes and student-question boxes ---- */

.protocol-box {
  background: white;
  border: 1px solid var(--line);
  border-left: 4px solid var(--teach);
  border-radius: 6px;
  padding: 1rem 1.25rem;
  margin: 1.5rem 0;
}

.protocol-box ol { margin: 0; padding-left: 1.2rem; }
.protocol-box li { margin-bottom: 0.9rem; }
.protocol-box li:last-child { margin-bottom: 0; }

.tag-inline {
  display: inline-block;
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.72rem;
  color: var(--muted);
  font-style: italic;
  margin-left: 0.3rem;
}

.student-questions {
  background: #f4eef7;
  border-left: 4px solid var(--teach);
  padding: 1rem 1.25rem;
  font-size: 0.98rem;
  margin: 1.75rem 0;
}

.student-questions ol { margin: 0.5rem 0 0 1.1rem; padding: 0; }
.student-questions li { margin-bottom: 0.6rem; }

.bloom-tag {
  display: inline-block;
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--teach);
  border: 1px solid var(--teach);
  border-radius: 10px;
  padding: 1px 8px;
  margin-left: 6px;
  white-space: nowrap;
}

/* ---- Number callout boxes (quick-reference figures) ---- */

.number-callout {
  background: white;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 1.1rem 1.25rem;
  margin: 1.25rem 0;
  text-align: center;
}

.number-callout .big-number {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 2.1rem;
  font-weight: 700;
  color: var(--teach);
  display: block;
  line-height: 1.15;
}

.number-callout .big-number-label {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.82rem;
  color: var(--muted);
  display: block;
  margin-top: 0.25rem;
}

.sol-tag {
  display: inline-block;
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--teal);
  background: #eef6f4;
  border-radius: 4px;
  padding: 2px 8px;
  margin: 0 0.3rem 0.3rem 0;
}

.quick-numbers-box {
  background: white;
  border: 1px solid var(--line);
  border-left: 4px solid var(--teal);
  border-radius: 6px;
  padding: 1.1rem 1.35rem;
  margin: 1.25rem 0;
}

.quick-numbers-box h3 {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.95rem;
  color: var(--teal);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin: 0 0 0.75rem 0;
}

.quick-numbers-box ul {
  margin: 0;
  padding-left: 1.1rem;
}

.quick-numbers-box li {
  margin-bottom: 0.65rem;
  font-size: 0.98rem;
}

.quick-numbers-box li:last-child { margin-bottom: 0; }

.quick-numbers-box .num {
  font-weight: 700;
  color: var(--teach);
  font-family: "Helvetica Neue", Arial, sans-serif;
}

.classroom-line {
  font-family: "Iowan Old Style", Georgia, serif;
  font-style: italic;
  background: #f7f5ef;
  border-left: 3px solid var(--muted);
  padding: 0.6rem 1rem;
  margin: 1rem 0;
  font-size: 1rem;
}

/* ---- Station cards (biotech stations lesson, etc.) ---- */

.station-card {
  background: white;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 1rem 1.25rem;
  margin: 1rem 0;
}

.station-card h3 {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 1.05rem;
  color: var(--teach);
  margin: 0 0 0.5rem 0;
}

.station-card .station-label {
  display: inline-block;
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--muted);
  font-weight: 700;
  margin-right: 0.4rem;
}

.station-card p { margin: 0.3rem 0; }

.station-card .hook {
  font-style: italic;
  color: var(--ink);
}

/* ---- AI prompt boxes and handout boxes ---- */

.prompt-box {
  background: #f4f6fa;
  border: 1px solid #c7d2e0;
  border-radius: 8px;
  padding: 1rem 1.25rem;
  margin: 1rem 0;
}

.prompt-box .prompt-label {
  display: block;
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: #3a5a8c;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.prompt-box p {
  font-family: "Menlo", "Courier New", monospace;
  font-size: 0.85rem;
  line-height: 1.6;
  margin: 0;
  color: var(--ink);
}

.book-quote {
  border-left: 3px solid var(--navy);
  padding: 0.3rem 0 0.3rem 1rem;
  margin: 1.25rem 0;
  font-family: "Iowan Old Style", Georgia, serif;
  font-style: italic;
  color: var(--ink);
}

.handout-box {
  background: white;
  border: 2px dashed var(--line);
  border-radius: 8px;
  padding: 1.25rem 1.5rem;
  margin: 1.5rem 0;
}

.handout-box .fill-line {
  display: block;
  border-bottom: 1px solid var(--muted);
  min-height: 1.6em;
  margin: 0.3rem 0 1rem 0;
}

/* ---- Real-case example boxes ---- */

.case-box {
  background: #fbf8f0;
  border: 1px solid #e3d9bf;
  border-left: 4px solid var(--chem);
  border-radius: 8px;
  padding: 1rem 1.25rem;
  margin: 1rem 0;
}

.case-box h3 {
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 1rem;
  color: var(--chem);
  margin: 0 0 0.5rem 0;
}

.case-box .case-label {
  display: inline-block;
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--muted);
  font-weight: 700;
  margin-right: 0.4rem;
}

.case-box p { margin: 0.4rem 0; }

/* ---- Teacher-only note box ---- */

.teacher-note {
  background: #eef1f6;
  border-left: 4px solid var(--navy);
  border-radius: 6px;
  padding: 1rem 1.25rem;
  margin: 1.25rem 0;
}

.teacher-note .teacher-label {
  display: block;
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--navy);
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.handout-box .handout-label {
  display: block;
  font-family: "Helvetica Neue", Arial, sans-serif;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--teach);
  font-weight: 700;
  margin-bottom: 0.6rem;
}

@media print {
  header.site-header, nav.site-nav, .back-link, footer.site-footer { display: none; }
  body { background: white; }
  article.onepager { padding: 0; max-width: 100%; }
}

/* ---- Tablet / iPad friendliness ---- */
@media (max-width: 900px) {
  header.site-header { padding: 1.4rem 1.1rem; }
  header.site-header h1 { font-size: 1.35rem; }
  main, article.onepager { padding-left: 1.1rem; padding-right: 1.1rem; }
  nav.site-nav a { padding: 0.75rem 1.1rem; font-size: 0.95rem; }
  ol.topic-list li { padding: 0.75rem 0; font-size: 1.1rem; }
  ol.topic-list li a { display: block; padding: 0.25rem 0; }
  article.onepager h1 { font-size: 1.6rem; }
  article.onepager p, article.onepager .check-understanding { font-size: 1.08rem; }
}