/* =====================================================================
   drtseng · course.css
   Course page for AI Multimedia (Spring 2027).
   Loads after styles.css and reuses its layout. Colors below override
   the styles.css palette with the Spring 2027 course poster colors
   (white, near-black, CSU green). The portfolio site (index.html) is
   not affected.
   ===================================================================== */

/* ---------- Poster palette ---------- */
:root {
  --bg:          #FFFFFF;
  --surface:     #F3F5F4;
  --hairline:    #C9CFCB;
  --ink:         #14171A;
  --muted:       #4A5450;
  --accent:      #006747;
  --accent-soft: rgba(0, 103, 71, 0.12);
}
::selection { background: var(--accent); color: #FFFFFF; }
::-webkit-scrollbar-track { background: var(--bg); }

.site-header { background: linear-gradient(to bottom, rgba(255,255,255,0.92), rgba(255,255,255,0)); }
.site-header.is-scrolled { background: rgba(255,255,255,0.95); }
.site-nav a.cta { color: #FFFFFF; }
.site-nav a.cta:hover { background: var(--ink); }
.hero::before { background: none; }

.hero__codes {
  font-family: var(--font-mono);
  font-size: clamp(16px, 2vw, 28px);
  letter-spacing: 0.02em;
  color: var(--accent);
}
.hero__headline--long {
  font-size: clamp(44px, 6.4vw, 104px);
  line-height: 1;
  max-width: 16ch;
}
.hero__headline em { font-style: normal; font-weight: 600; }
.hero__grid { gap: var(--s-5); }
.hero { border-top: 4px solid var(--accent); }

/* Video and image frames stay dark; text on them stays light */
.work-item__player,
.tile { box-shadow: none; }
.work-item__expand { color: #FFFFFF; }
.work-item__expand .caption { color: #FFFFFF; }
.work-item__expand:hover { color: #FFFFFF; }
.tile { color: #FFFFFF; }
.tile .caption.muted { color: rgba(255,255,255,0.75); }
.modal__close { color: #FFFFFF; border-color: rgba(255,255,255,0.3); }
.slot--portrait video { border-color: var(--hairline); }

.course-table__wide { grid-column: 1 / -1; }
.course-table__wide dd { font-size: clamp(18px, 1.8vw, 24px); }

/* Placeholder marker · remove the class once the value is filled in */
.tbd {
  outline: 1px dashed var(--accent);
  outline-offset: 3px;
  color: var(--accent);
}

.hero__headline { max-width: none; }

/* Talk sections · one block per part of the talk */
.block {
  padding-bottom: var(--s-10);
  border-top: 1px solid var(--hairline);
}
.section-header--sub { padding-top: var(--s-9); padding-bottom: var(--s-5); }

.link {
  color: var(--ink);
  border-bottom: 1px solid var(--accent);
  transition: color var(--d-fast) var(--ease);
}
.link:hover { color: var(--accent); }

/* ---------- Split layout: media left, facts right ---------- */
.split {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--s-7);
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
  gap: var(--s-8);
  align-items: center;
}
.split--video {
  grid-template-columns: auto minmax(0, 1fr);
  margin-top: var(--s-9);
}
.split--video .tile-player { height: 64vh; }

.facts {
  display: flex;
  flex-direction: column;
  gap: var(--s-5);
}

/* ---------- Media slots with placeholder label ---------- */
.slot {
  position: relative;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: var(--s-3);
}
.slot img,
.slot video {
  position: relative;
  z-index: 1;
  width: 100%;
  border-radius: 4px;
  border: 1px solid var(--hairline);
  background: var(--surface);
}
.slot--landscape::before,
.slot--portrait::before {
  content: "";
  display: block;
  border-radius: 4px;
  background: var(--surface);
  border: 1px solid var(--hairline);
}
.slot--landscape::before { aspect-ratio: 16 / 9; }
.slot--landscape:has(img)::before { display: none; }
.slot--portrait { height: 70vh; aspect-ratio: 9 / 16; }
.slot--portrait::before { position: absolute; inset: 0; }
.slot--portrait video { height: 100%; object-fit: cover; }
.slot__label {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  white-space: nowrap;
}
.slot--landscape .slot__label { top: calc(50% - 12px); }
.slot .work-item__expand { z-index: 2; }

/* ---------- Stat list ---------- */
.stat-list {
  margin: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--s-5) var(--s-6);
}
.stat-list div {
  display: flex;
  flex-direction: column;
  gap: var(--s-2);
  padding-top: var(--s-3);
  border-top: 1px solid var(--hairline);
}
.stat-list dd {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: clamp(28px, 3.2vw, 44px);
  letter-spacing: -0.02em;
  line-height: 1;
}
.stat-list--compact dd { font-size: clamp(20px, 2vw, 28px); }

.workflow { display: flex; flex-direction: column; gap: var(--s-3); }
.workflow__steps {
  margin: 0;
  padding-left: var(--s-5);
  color: var(--muted);
  font-size: 15px;
  display: flex;
  flex-direction: column;
  gap: var(--s-1);
}
.workflow__steps li::marker {
  color: var(--accent);
  font-family: var(--font-mono);
  font-size: 12px;
}
.source { text-transform: none; letter-spacing: 0.04em; }

/* ---------- Majors ---------- */
.majors {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--s-7);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--hairline);
  border-top: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
}
.major {
  background: var(--bg);
  padding: var(--s-8) var(--s-7);
  display: flex;
  flex-direction: column;
  gap: var(--s-6);
}
.major__title {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: clamp(26px, 2.8vw, 38px);
  letter-spacing: -0.02em;
  margin: 0;
  color: var(--accent);
}

.points {
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: var(--s-5);
}
.points dt {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 18px;
  color: var(--ink);
  margin-bottom: var(--s-1);
}
.points dd {
  margin: 0;
  font-size: 15px;
  line-height: 1.55;
  color: var(--muted);
  max-width: 46ch;
}
.points--grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: var(--s-6);
}

/* ---------- Course ---------- */
.capability-grid { grid-template-columns: repeat(2, 1fr); }
.skills,
.requirements {
  max-width: var(--max-w);
  margin: var(--s-8) auto 0;
  padding: 0 var(--s-7);
  display: flex;
  flex-direction: column;
  gap: var(--s-5);
}
.requirements {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--s-6);
}
.requirements > div {
  display: flex;
  flex-direction: column;
  gap: var(--s-2);
  padding-top: var(--s-3);
  border-top: 1px solid var(--hairline);
  font-size: 16px;
}
.requirements .tbd { align-self: flex-start; }

/* ---------- Gallery ---------- */
.gallery {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--s-7);
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: var(--s-4);
}
.tile {
  position: relative;
  padding: 0;
  border: 1px solid var(--hairline);
  border-radius: 4px;
  overflow: hidden;
  background: #000;
  aspect-ratio: 9 / 16;
  text-align: left;
  color: var(--ink);
  transition: border-color var(--d-fast) var(--ease), transform var(--d-fast) var(--ease);
}
.tile img,
.tile video {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.tile video { position: absolute; inset: 0; }
.tile:hover { border-color: var(--accent); transform: translateY(-3px); }
.tile__meta {
  position: absolute;
  left: 0; right: 0; bottom: 0;
  z-index: 1;
  padding: var(--s-6) var(--s-3) var(--s-3);
  display: flex;
  flex-direction: column;
  gap: 2px;
  background: linear-gradient(to top, rgba(10,10,10,0.9), rgba(10,10,10,0));
}
.tile__title {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 15px;
}

/* ---------- Evidence ---------- */
.evidence {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--s-7);
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: var(--s-8);
  align-items: start;
}
.evidence__side {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: var(--s-6);
  align-items: start;
}
.speaker {
  grid-column: 1 / -1;
  padding-top: var(--s-4);
  border-top: 1px solid var(--hairline);
  display: flex;
  flex-direction: column;
  gap: var(--s-2);
}
.speaker p {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(20px, 2vw, 28px);
  letter-spacing: -0.015em;
  line-height: 1.25;
}

/* ---------- Register ---------- */
.register__grid {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--s-7);
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: var(--s-9);
  align-items: center;
}
.course-table {
  margin: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--s-5) var(--s-7);
}
.course-table div {
  display: flex;
  flex-direction: column;
  gap: var(--s-2);
  padding-top: var(--s-3);
  border-top: 1px solid var(--hairline);
}
.course-table dd {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: clamp(22px, 2.4vw, 34px);
  letter-spacing: -0.02em;
  align-self: flex-start;
}
.qr {
  position: relative;
  margin: 0;
  width: min(320px, 70vw);
  display: flex;
  flex-direction: column;
  gap: var(--s-3);
  align-items: center;
}
.qr::before {
  content: "";
  display: block;
  width: 100%;
  aspect-ratio: 1;
  background: var(--surface);
  border: 1px solid var(--hairline);
  border-radius: 4px;
}
.qr:has(img)::before { display: none; }
.qr img { width: 100%; aspect-ratio: 1; background: #fff; border-radius: 4px; padding: 12px; }
.qr .slot__label { top: calc(50% - 14px); }

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
  .split,
  .split--video,
  .majors,
  .evidence,
  .register__grid {
    grid-template-columns: 1fr;
    padding: 0 var(--s-5);
    gap: var(--s-6);
  }
  .split--video .tile-player,
  .slot--portrait { height: 60vh; margin: 0 auto; }
  .major { padding: var(--s-7) var(--s-5); }
  .gallery { grid-template-columns: repeat(3, minmax(0, 1fr)); padding: 0 var(--s-5); }
  .points--grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .requirements { grid-template-columns: 1fr; }
  .skills, .requirements { padding: 0 var(--s-5); }
  .qr { margin: 0 auto; }
}
@media (max-width: 600px) {
  .site-nav a:not(.cta) { display: none; }
  .gallery { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .points--grid,
  .evidence__side,
  .course-table { grid-template-columns: 1fr; }
}

/* Hairline grids: inset with margin so the divider color does not show in the side padding */
.majors,
.capability-grid {
  padding: 0;
  width: calc(100% - 2 * var(--s-7));
  max-width: calc(var(--max-w) - 2 * var(--s-7));
}
@media (max-width: 1024px) {
  .majors,
  .capability-grid { width: calc(100% - 2 * var(--s-5)); padding: 0; }
}

/* Gallery text sits on video frames: keep it light */
.gallery .tile,
.gallery .tile__title { color: #FFFFFF; }

/* 8 example videos: 4 per row */
.gallery { grid-template-columns: repeat(4, minmax(0, 1fr)); }
@media (max-width: 1024px) { .gallery { grid-template-columns: repeat(3, minmax(0, 1fr)); } }
@media (max-width: 600px) { .gallery { grid-template-columns: repeat(2, minmax(0, 1fr)); } }

/* ---------- Demand section ---------- */
.split--stats { grid-template-columns: 1fr; gap: var(--s-4); }
.stat-list--three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.stat-list--three dd { font-size: clamp(48px, 6vw, 96px); color: var(--accent); }
.stat-list--three dt { max-width: 30ch; }
.section-header__title--sub { font-size: clamp(24px, 3vw, 40px); }

/* ---------- Instructor block ---------- */
.instructor {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--s-7);
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: var(--s-6);
  align-items: start;
}
.instructor .recognition__wide { align-self: start; }

@media (max-width: 1024px) {
  .instructor { grid-template-columns: 1fr; padding: 0 var(--s-5); }
}
@media (max-width: 600px) {
  .stat-list--three { grid-template-columns: 1fr; }
}
.stat-list--three div { justify-content: space-between; }

/* ---------- Kalshi example ---------- */
.kalshi {
  max-width: var(--max-w);
  margin: var(--s-9) auto 0;
  padding: 0 var(--s-7);
  display: flex;
  flex-direction: column;
  gap: var(--s-3);
}
.kalshi img {
  width: min(720px, 100%);
  border-radius: 4px;
  border: 1px solid var(--hairline);
}

/* =====================================================================
   PROJECTOR SCALE
   Minimum sizes for text read from the back of a classroom.
   Body text 20px+, labels 15px+, headings unchanged or larger.
   ===================================================================== */
body { font-size: 20px; }
.caption { font-size: 15px; letter-spacing: 0.08em; }
.brand-mark__name { font-size: 22px; }
.brand-mark__sub { font-size: 13px; }
.site-nav a { font-size: 15px; }

.hero__eyebrow { font-size: 16px; }
.hero__sub { font-size: clamp(22px, 2vw, 30px); max-width: 48ch; }

.section-header__title { font-size: clamp(36px, 4.4vw, 64px); }
.section-header__sub { font-size: 22px; max-width: 60ch; }
.section-header__title--sub { font-size: clamp(30px, 3.4vw, 48px); }

.stat-list--three dt { font-size: 16px; }
.source { font-size: 15px; }

.major__title { font-size: clamp(30px, 3.2vw, 44px); }
.points dt { font-size: 26px; }
.points dd { font-size: 21px; line-height: 1.45; max-width: 52ch; }
.points--grid dt { font-size: 24px; }
.points--grid dd { font-size: 20px; }

.capability__title { font-size: clamp(30px, 3vw, 42px); }
.capability p { font-size: 22px; max-width: 44ch; }

.requirements > div { font-size: 22px; }

.tile__meta { padding: var(--s-8) var(--s-4) var(--s-4); }
.tile__title { font-size: 22px; line-height: 1.2; }
.tile .caption { font-size: 14px; }

.speaker p { font-size: clamp(24px, 2.4vw, 34px); }
.course-table dd { font-size: clamp(28px, 2.8vw, 40px); }
.qr figcaption { font-size: 15px; }
.site-footer__grid .caption { font-size: 14px; }

@media (max-width: 600px) {
  body { font-size: 17px; }
  .points dd, .capability p, .requirements > div { font-size: 18px; }
  .points dt { font-size: 21px; }
  .site-nav a { font-size: 12px; }
}
.points--grid { grid-template-columns: repeat(3, minmax(0, 1fr)); row-gap: var(--s-7); }
.kalshi figcaption { font-size: 18px; }
@media (max-width: 1024px) { .points--grid { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 600px) { .points--grid { grid-template-columns: 1fr; } }

/* =====================================================================
   HEADING HIERARCHY
   h1  hero course title
   h2  section title (one per numbered section)
   h3  sub-block title (.subsection__title), same style in every section
   h4  column title inside a sub-block (.columns__title)
   ===================================================================== */

/* Hero course codes */
.hero__codes {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: var(--s-2);
  font-family: var(--font-mono);
  font-size: clamp(24px, 2.8vw, 40px);
  letter-spacing: 0;
  color: var(--accent);
}
.hero__codes li { display: flex; flex-wrap: wrap; align-items: baseline; gap: var(--s-4); }
.hero__level {
  font-size: 0.5em;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
}

.section-header__lead {
  margin: var(--s-2) 0 0;
  font-family: var(--font-display);
  font-size: clamp(24px, 2.4vw, 34px);
  line-height: 1.3;
  color: var(--muted);
  max-width: 40ch;
}

/* Sub-blocks */
.subsection {
  max-width: var(--max-w);
  margin: var(--s-9) auto 0;
  padding: 0 var(--s-7);
  display: flex;
  flex-direction: column;
  gap: var(--s-5);
}
.subsection__title {
  margin: 0;
  padding-top: var(--s-4);
  border-top: 1px solid var(--hairline);
  font-family: var(--font-display);
  font-weight: 500;
  font-size: clamp(30px, 3vw, 42px);
  letter-spacing: -0.02em;
  line-height: 1.15;
  color: var(--ink);
}
.subsection__text {
  margin: 0;
  font-size: clamp(22px, 2vw, 28px);
  line-height: 1.4;
  color: var(--ink);
  max-width: 44ch;
}
.subsection .gallery,
.subsection .instructor { padding: 0; margin: 0; max-width: none; }

/* Columns of bullet lists */
.columns {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--s-7);
}
.columns--three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.columns__title {
  margin: 0 0 var(--s-3);
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(24px, 2.2vw, 30px);
  color: var(--accent);
}
.bullets {
  margin: 0;
  padding-left: 1.1em;
  display: flex;
  flex-direction: column;
  gap: var(--s-2);
  font-size: clamp(22px, 2vw, 28px);
  line-height: 1.3;
  color: var(--ink);
}
.bullets li::marker { color: var(--accent); }

/* Requirements */
.requirements {
  margin: 0;
  padding: 0;
  max-width: none;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--s-6);
}
.requirements > div { border-top: none; padding-top: 0; display: flex; flex-direction: column; gap: var(--s-2); }
.requirements dd { margin: 0; font-size: clamp(22px, 2vw, 28px); }

/* Register */
.register__info { display: flex; flex-direction: column; gap: var(--s-7); }
.offerings { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--s-7); }
.offering { display: flex; flex-direction: column; gap: var(--s-2); }
.offering__course {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(20px, 1.8vw, 26px);
  color: var(--accent);
}
.offering__nbr { margin: 0; font-size: clamp(22px, 2vw, 28px); display: flex; gap: var(--s-3); align-items: baseline; }
.course-table dd { font-size: clamp(24px, 2.4vw, 34px); }

@media (max-width: 1024px) {
  .subsection { padding: 0 var(--s-5); }
  .columns--three { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 600px) {
  .columns, .columns--three, .requirements, .offerings { grid-template-columns: 1fr; }
}
.section-header + .subsection { margin-top: var(--s-4); }
.block > .subsection:last-child { margin-bottom: 0; }

.columns__note { margin: calc(-1 * var(--s-2)) 0 var(--s-4); }