/* Self-hosted Source Sans Pro (Cosmo's font; SIL Open Font License, fonts/OFL.txt).
   Replaces Cosmo's Google Fonts import, which theme-fonts.scss switches off. */
@font-face {
  font-family: "Source Sans Pro";
  font-style: normal;
  font-weight: 300;
  font-display: swap;
  src: url("fonts/source-sans-pro-latin-ext-300-normal.woff2") format("woff2");
  unicode-range: U+0100-02AF,U+0304,U+0308,U+0329,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20CF,U+2113,U+2C60-2C7F,U+A720-A7FF;
}

@font-face {
  font-family: "Source Sans Pro";
  font-style: normal;
  font-weight: 300;
  font-display: swap;
  src: url("fonts/source-sans-pro-latin-300-normal.woff2") format("woff2");
  unicode-range: U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+2074,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD;
}

@font-face {
  font-family: "Source Sans Pro";
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url("fonts/source-sans-pro-latin-ext-400-normal.woff2") format("woff2");
  unicode-range: U+0100-02AF,U+0304,U+0308,U+0329,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20CF,U+2113,U+2C60-2C7F,U+A720-A7FF;
}

@font-face {
  font-family: "Source Sans Pro";
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url("fonts/source-sans-pro-latin-400-normal.woff2") format("woff2");
  unicode-range: U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+2074,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD;
}

@font-face {
  font-family: "Source Sans Pro";
  font-style: normal;
  font-weight: 700;
  font-display: swap;
  src: url("fonts/source-sans-pro-latin-ext-700-normal.woff2") format("woff2");
  unicode-range: U+0100-02AF,U+0304,U+0308,U+0329,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20CF,U+2113,U+2C60-2C7F,U+A720-A7FF;
}

@font-face {
  font-family: "Source Sans Pro";
  font-style: normal;
  font-weight: 700;
  font-display: swap;
  src: url("fonts/source-sans-pro-latin-700-normal.woff2") format("woff2");
  unicode-range: U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+2074,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD;
}

/* =========================================================
   Homepage
   ========================================================= */

section.overview-title > h1 {
  display: none;
}

.ml-home {
  --buas-orange: #f47a20;
  --buas-blue: #00558c;
  --ink: #1f2937;
  --muted: #667085;
  --soft: #f6f8fb;
  --line: #e6e9ef;
  --card: #ffffff;
  color: var(--ink);
}

.ml-home * {
  box-sizing: border-box;
}

/* Hero buttons jump to in-page sections: scroll smoothly, keep a little space above. */
html {
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}

#the-client,
#course-structure {
  scroll-margin-top: 1.5rem;
}

.ml-hero {
  display: grid;
  grid-template-columns: 1.4fr 0.6fr;
  min-height: 480px;

  border-radius: 26px;
  overflow: hidden;
  background: linear-gradient(135deg, #f7fbff 0%, #ffffff 60%);
  border: 1px solid var(--line);
  box-shadow: 0 18px 55px rgba(18, 38, 63, 0.10);
  margin: 0.5rem 0 1.2rem 0;
}

.ml-hero-copy {
  padding: 2.6rem 3.2rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.ml-brand {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 2.1rem;
}

/* Quarto wraps the image in a paragraph */
.ml-brand > p {
  margin: 0;
  flex: 0 0 auto;
  line-height: 0;
}

.ml-brand img {
  width: 180px;
  max-width: 100%;
  height: auto;
  display: block;
  margin: 0;
}

.ml-program {
  padding-left: 1rem;
  border-left: 2px solid var(--buas-orange);
  font-size: 0.95rem;
  line-height: 1.35;
  color: var(--muted);
}

.ml-kicker {
  display: inline-block;
  width: fit-content;
  color: var(--buas-blue);
  background: #eaf5fb;
  border-radius: 999px;
  padding: 0.45rem 0.8rem;
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 1rem;
}

.ml-hero-title {
  font-size: clamp(2.1rem, 3.3vw, 3.2rem);
  line-height: 1.02;
  letter-spacing: -0.04em;
  margin: 0 0 1.1rem 0;
  font-weight: 850;
}

.ml-hero-title .hero-line {
  display: block;
}

.ml-hero-title .accent {
  color: var(--buas-orange);
}

.ml-lead {
  font-size: 1.17rem;
  line-height: 1.65;
  color: #475467;
  max-width: 560px;
  margin-bottom: 1.5rem;
}

.ml-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 0.4rem;
}

.ml-btn {
  display: inline-block;
  text-decoration: none !important;
  border-radius: 10px;
  padding: 0.72rem 1rem;
  font-weight: 750;
  border: 1px solid transparent;
}

.ml-btn-primary {
  background: var(--buas-orange);
  color: white !important;
}

.ml-btn-secondary {
  background: white;
  color: var(--buas-blue) !important;
  border-color: #cfd8e3;
}

.ml-hero-image {
  min-height: 520px;
  background: url("images/ml-opv-hero.png") center center / cover no-repeat;
}

.ml-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  margin: 1.2rem 0 3.8rem 0;
}

.ml-stat {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 1.25rem 1.3rem;
}

.ml-stat strong {
  display: block;
  font-size: 1.75rem;
  color: var(--buas-blue);
  line-height: 1;
  margin-bottom: 0.4rem;
}

.ml-stat span {
  color: var(--muted);
  font-size: 0.92rem;
}

.ml-course-info-wrap {
  margin: 1.2rem 0 4rem 0;
}

.ml-course-info {
  display: grid;
  grid-template-columns: 1.15fr 1.3fr 1.7fr 1.6fr;
  background: white;
  border: 1px solid var(--line);
  border-radius: 18px;
  overflow: hidden;
}

.ml-course-info-item {
  padding: 1.2rem 1rem;
  min-height: 110px;
  border-right: 1px solid var(--line);
}

.ml-course-info-item:last-child {
  border-right: 0;
}

.ml-course-info-item.lead {
  background: #f3f9fd;
}

.ml-course-info-label {
  color: var(--buas-orange);
  font-size: 0.72rem;
  font-weight: 850;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  margin-bottom: 0.45rem;
}

.ml-course-info-value {
  color: var(--ink);
  font-size: 0.92rem;
  font-weight: 750;
  line-height: 1.35;
  white-space: nowrap;
}

.ml-course-info-meta {
  color: var(--muted);
  font-size: 0.86rem;
  line-height: 1.4;
  margin-top: 0.2rem;
}

.ml-section {
  margin: 4.4rem 0;
}

.ml-section-head {
  max-width: 820px;
  margin-bottom: 1.7rem;
}

.ml-eyebrow {
  color: var(--buas-orange);
  font-size: 0.8rem;
  font-weight: 850;
  text-transform: uppercase;
  letter-spacing: 0.11em;
  margin-bottom: 0.45rem;
}

.ml-section h2 {
  font-size: clamp(1.9rem, 3vw, 2.7rem);
  letter-spacing: -0.025em;
  margin: 0 0 0.65rem 0;
}

.ml-section-head p,
.ml-client-copy p,
.ml-track p,
.ml-diff-card p,
.ml-model-card p,
.ml-step p,
.ml-journey-item p {
  color: var(--muted);
  line-height: 1.65;
}

.ml-difference {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
}

.ml-diff-card {
  border-radius: 18px;
  padding: 1.4rem;
  background: var(--soft);
  border: 1px solid var(--line);
}

.ml-diff-card .num {
  width: 2rem;
  height: 2rem;
  display: grid;
  place-items: center;
  border-radius: 8px;
  color: white;
  background: var(--buas-blue);
  font-weight: 800;
  margin-bottom: 1rem;
}

.ml-diff-card h3 {
  font-size: 1.05rem;
  margin-bottom: 0.45rem;
}

/* Video on top, full card width; text below. */
.ml-client {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.8rem;
  background: #102f46;
  color: white;
  padding: 2.1rem;
  border-radius: 24px;
}

.ml-client-copy p {
  color: #d7e3ea;
}

.ml-client-copy h2 {
  color: white;
}

.ml-client-copy a {
  color: #ffd0ac;
}

.ml-video {
  position: relative;
  width: 100%;
  padding-top: 56.25%;
  overflow: hidden;
  border-radius: 16px;
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.22);
}

.ml-video iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
}

/* ---------- Click-to-load video poster ---------- */
.ml-video-poster {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  padding: 0;
  border: 0;
  cursor: pointer;
  overflow: hidden;
  text-align: left;
  font: inherit;
  color: white;
  background:
    radial-gradient(55% 75% at 78% 112%, rgba(244, 122, 32, 0.55), transparent 62%),
    radial-gradient(45% 60% at 70% 50%, rgba(0, 133, 210, 0.28), transparent 70%),
    radial-gradient(60% 70% at 0% 0%, rgba(0, 85, 140, 0.55), transparent 70%),
    linear-gradient(135deg, #081c2c 0%, #0f3350 55%, #0b2539 100%);
}

.ml-video-poster:focus-visible {
  outline: 3px solid var(--buas-orange);
  outline-offset: -3px;
}

.ml-video-lattice {
  position: absolute;
  inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='56' height='97' viewBox='0 0 56 97'%3E%3Cpath d='M28 0 L56 16 L56 48 L28 64 L0 48 L0 16 Z M28 64 L28 97' fill='none' stroke='%23ffffff' stroke-opacity='0.09' stroke-width='1'/%3E%3C/svg%3E");
  background-size: 56px 97px;
  -webkit-mask-image: linear-gradient(100deg, transparent 25%, #000 80%);
  mask-image: linear-gradient(100deg, transparent 25%, #000 80%);
}

/* Molecule orbiting the play button; play sits in the benzene ring. */
.ml-video-molecule {
  position: absolute;
  top: 50%;
  left: 72%;
  width: min(52%, 34rem);
  transform: translate(-50%, -50%);
  overflow: visible;
}

.ml-video-molecule > g {
  transform-origin: 200px 200px;
  animation: ml-orbit 90s linear infinite;
}

.ml-video-molecule .bonds polygon,
.ml-video-molecule .bonds line {
  fill: none;
  stroke: rgba(255, 255, 255, 0.28);
  stroke-width: 2.5;
  stroke-linecap: round;
}

.ml-video-molecule .bonds .inner {
  stroke: rgba(255, 255, 255, 0.12);
}

.ml-video-molecule .atoms circle {
  fill: #dbe7f0;
  opacity: 0.75;
}

.ml-video-molecule .atoms .o { fill: #ff8a3d; opacity: 0.95; }
.ml-video-molecule .atoms .n { fill: #3aa0ff; opacity: 0.95; }
.ml-video-molecule .atoms .s { fill: #ffcf4a; opacity: 0.95; }
.ml-video-molecule .atoms .h { fill: #ffffff; opacity: 0.55; }

@keyframes ml-orbit {
  to { transform: rotate(360deg); }
}

.ml-video-play {
  position: absolute;
  top: 50%;
  left: 72%;
  width: clamp(3.6rem, 8vw, 5.4rem);
  aspect-ratio: 1;
  transform: translate(-50%, -50%);
  border-radius: 50%;
  background: var(--buas-orange);
  box-shadow: 0 10px 34px rgba(244, 122, 32, 0.55);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

/* Play triangle */
.ml-video-play::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 54%;
  transform: translate(-50%, -50%);
  border-style: solid;
  border-width: 0.62em 0 0.62em 1.05em;
  border-color: transparent transparent transparent white;
  font-size: clamp(0.9rem, 1.8vw, 1.25rem);
}

/* Pulsing ring */
.ml-video-play::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 2px solid rgba(244, 122, 32, 0.8);
  animation: ml-ring 2.4s ease-out infinite;
}

@keyframes ml-ring {
  0% { transform: scale(1); opacity: 0.9; }
  100% { transform: scale(1.9); opacity: 0; }
}

.ml-video-poster:hover .ml-video-play,
.ml-video-poster:focus-visible .ml-video-play {
  transform: translate(-50%, -50%) scale(1.08);
  box-shadow: 0 14px 44px rgba(244, 122, 32, 0.75);
}

.ml-video-text {
  position: absolute;
  left: 7%;
  bottom: 13%;
  max-width: 46%;
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.ml-video-kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--buas-orange);
  font-size: 0.78rem;
  font-weight: 850;
  text-transform: uppercase;
  letter-spacing: 0.14em;
}

.ml-video-kicker::before {
  content: "";
  width: 1.6rem;
  height: 2px;
  background: currentColor;
}

.ml-video-title {
  font-size: clamp(1.35rem, 3.1vw, 2.5rem);
  font-weight: 800;
  line-height: 1.08;
  letter-spacing: -0.02em;
  text-wrap: balance;
}

.ml-video-source {
  color: #b8cad8;
  font-size: clamp(0.78rem, 1.2vw, 0.92rem);
}

.ml-video-consent {
  position: absolute;
  right: 1.1rem;
  bottom: 0.9rem;
  color: rgba(255, 255, 255, 0.55);
  font-size: 0.72rem;
  letter-spacing: 0.02em;
}

.ml-video-fallback {
  position: absolute;
  inset: auto 0 0 0;
  padding: 0.8rem;
  text-align: center;
  color: white;
}

@media (prefers-reduced-motion: reduce) {
  .ml-video-molecule > g,
  .ml-video-play::after {
    animation: none;
  }
}

/* Narrow: molecule + play move to the upper right, text spans wider. */
@media (max-width: 680px) {
  .ml-video-molecule,
  .ml-video-play {
    top: 32%;
    left: 81%;
  }

  .ml-video-molecule {
    width: 46%;
  }

  .ml-video-text {
    left: 6%;
    bottom: 10%;
    max-width: 60%;
    gap: 0.35rem;
  }

  .ml-video-kicker {
    font-size: 0.66rem;
  }

  .ml-video-consent {
    display: none;
  }
}

.ml-pipeline img {
  width: 100%;
  border-radius: 20px;
  margin: 0.3rem 0 1.3rem 0;
  border: 1px solid var(--line);
}

.ml-model-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
}

.ml-model-card {
  background: white;
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 1.5rem;
  border-top: 4px solid var(--buas-orange);
}

.ml-model-card .tag {
  color: var(--buas-blue);
  font-size: 0.75rem;
  font-weight: 850;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.ml-model-card h3 {
  margin: 0.45rem 0;
}

/* Student testimonials: one featured quote + three compact quotes. */
.ml-quotes {
  display: grid;
  grid-template-columns: 1.15fr 1fr;
  gap: 1.1rem;
}

.ml-quote {
  position: relative;
  display: flex;
  flex-direction: column;
  background: white;
  border: 1px solid var(--line);
  border-left: 4px solid var(--buas-orange);
  border-radius: 16px;
  padding: 1.2rem 1.4rem;
}

.ml-quote-featured {
  grid-row: span 3;
  background: #102f46;
  border: 0;
  border-radius: 24px;
  padding: 2.4rem 2.4rem 2.2rem;
  color: white;
  overflow: hidden;
}

/* Large decorative quotation mark. */
.ml-quote-featured::before {
  content: "\201C";
  position: absolute;
  top: 1.1rem;
  right: 1.8rem;
  font-family: Georgia, "Times New Roman", serif;
  font-size: 7.5rem;
  line-height: 1;
  color: var(--buas-orange);
  opacity: 0.45;
  pointer-events: none;
}

.ml-quote-tag {
  color: var(--buas-orange);
  font-size: 0.72rem;
  font-weight: 850;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 0.55rem;
}

.ml-quote blockquote,
.ml-quote .blockquote {
  margin: 0 0 0.7rem 0;
  padding: 0;
  border: 0;
  font-size: 1.02rem;
  line-height: 1.55;
  color: var(--ink);
}

.ml-quote blockquote p {
  margin: 0;
}

.ml-quote-featured blockquote,
.ml-quote-featured .blockquote {
  position: relative;
  font-size: clamp(1.3rem, 2vw, 1.65rem);
  font-weight: 600;
  line-height: 1.45;
  letter-spacing: -0.01em;
  color: white;
  margin-bottom: 1.6rem;
}

.ml-quote-by {
  margin-top: auto;
  color: var(--muted);
  font-size: 0.85rem;
}

/* Centre tag + quote vertically; attribution stays at the bottom. */
.ml-quote-featured .ml-quote-tag {
  margin-top: auto;
}

.ml-quote-featured .ml-quote-by {
  color: #b8cad8;
  padding-top: 1rem;
  border-top: 1px solid rgba(255, 255, 255, 0.16);
}

.ml-progress {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  margin-top: 1.4rem;
}

.ml-step {
  padding: 1.6rem;
  background: white;
  border: 1px solid var(--line);
}

.ml-step:first-child {
  border-radius: 16px 0 0 16px;
}

.ml-step:last-child {
  border-radius: 0 16px 16px 0;
}

.ml-step + .ml-step {
  border-left: 0;
}

.ml-step strong {
  color: var(--buas-blue);
}

.ml-step p {
  margin-bottom: 0;
}

/* Structure: Learn -> Apply -> Demonstrate, as three connected stages. */
.ml-tracks {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2.4rem;
}

.ml-track {
  --accent: var(--buas-blue);
  --accent-soft: #eaf2f8;
  position: relative;
  display: flex;
  flex-direction: column;
  border: 1px solid var(--line);
  border-top: 5px solid var(--accent);
  border-radius: 18px;
  padding: 1.6rem 1.5rem 1.4rem;
  background: white;
  box-shadow: 0 10px 26px rgba(16, 47, 70, 0.07);
}

.ml-track:nth-child(2) {
  --accent: var(--buas-orange);
  --accent-soft: #fef1e7;
}

.ml-track:nth-child(3) {
  --accent: #138a7a;
  --accent-soft: #e6f5f2;
}

/* Chevron in the gap pointing to the next stage. */
.ml-track:not(:last-child)::after {
  content: "";
  position: absolute;
  top: 50%;
  right: calc(-1.2rem - 0.42rem);
  width: 0.85rem;
  height: 0.85rem;
  border-top: 3px solid #b8c2cf;
  border-right: 3px solid #b8c2cf;
  transform: translateY(-50%) rotate(45deg);
}

.ml-track h3 {
  font-size: 1.3rem;
  margin: 0 0 0.6rem 0;
}

.ml-track > p {
  color: var(--ink);
  font-weight: 600;
  line-height: 1.5;
  margin-bottom: 1.1rem;
}

.ml-track ul {
  list-style: none;
  padding: 1.1rem 0 0 0;
  margin: 0;
  border-top: 1px solid var(--line);
}

.ml-track li {
  position: relative;
  padding-left: 1.6rem;
  margin-bottom: 0.6rem;
  color: var(--muted);
  line-height: 1.5;
}

.ml-track li:last-child {
  margin-bottom: 0;
}

.ml-track li::before {
  content: "";
  position: absolute;
  left: 0.2rem;
  top: 0.45em;
  width: 0.6rem;
  height: 0.6rem;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 4px var(--accent-soft);
}

.ml-journey {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0.75rem;
}

.ml-journey-item {
  min-height: 165px;
  border-radius: 16px;
  padding: 1.25rem;
  background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%);
  border: 1px solid var(--line);
}

.ml-journey-item .week {
  color: var(--buas-orange);
  font-size: 0.75rem;
  font-weight: 850;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.ml-journey-item h3 {
  font-size: 1rem;
  margin: 0.5rem 0;
}

.ml-journey-item p {
  font-size: 0.89rem;
  margin-bottom: 0;
}

.ml-note {
  background: #fff8f1;
  border-left: 4px solid var(--buas-orange);
  padding: 1rem 1.2rem;
  border-radius: 0 12px 12px 0;
  color: #69482d;
  font-size: 0.92rem;
  margin-top: 1.4rem;
}

.ml-footer-cta {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 1.5rem;
  align-items: center;
  background: linear-gradient(120deg, #00558c, #0a3651);
  color: white;
  border-radius: 22px;
  padding: 2rem 2.2rem;
  margin: 4rem 0 1rem 0;
}

.ml-footer-cta h2 {
  color: white;
  margin: 0 0 0.35rem 0;
}

.ml-footer-cta p {
  color: #dce9f0;
  margin: 0;
}


.ml-textbook {
  background: white;
  border: 1px solid var(--line);
  border-left: 4px solid var(--buas-blue);
  border-radius: 0 16px 16px 0;
  padding: 1.4rem 1.8rem;
  margin-top: 0.75rem;
}

.ml-textbook-label {
  color: var(--buas-blue);
  font-size: 0.72rem;
  font-weight: 850;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  margin-bottom: 0.45rem;
}

.ml-textbook-title {
  font-size: 1.07rem;
  font-weight: 750;
  color: var(--ink);
  line-height: 1.35;
  margin-bottom: 0.3rem;
}

.ml-textbook-meta {
  color: var(--muted);
  font-size: 0.9rem;
}

.ml-prereq-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  margin-top: 0.75rem;
}

.ml-prereq-card {
  background: var(--soft);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 1.3rem 1.4rem;
}

.ml-prereq-card h3 {
  font-size: 1rem;
  margin: 0 0 0.5rem 0;
  color: var(--ink);
}

.ml-prereq-card p {
  font-size: 0.875rem;
  margin: 0;
  line-height: 1.55;
}

/* Course resources (repository, Kaggle) with a status badge. */
.ml-resource-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
  margin-top: 0.75rem;
}

.ml-resource-card {
  background: white;
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 1.4rem 1.5rem 1.5rem;
  box-shadow: 0 6px 18px rgba(16, 47, 70, 0.05);
}

.ml-resource-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1rem;
}

/* Pandoc wraps the inline logo + badge in a <p>; let them be flex items. */
.ml-resource-top > p {
  display: contents;
}

.ml-resource-logo {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.75rem;
  height: 2.75rem;
  border-radius: 12px;
  background: var(--soft);
  border: 1px solid var(--line);
}

.ml-resource-logo img {
  width: 1.45rem;
  height: 1.45rem;
}

.ml-resource-logo-wide {
  width: auto;
  padding: 0 0.85rem;
  background: #eef9ff;
  border-color: #d3efff;
}

.ml-resource-logo-wide img {
  width: auto;
  height: 1.05rem;
}

.ml-status {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.28rem 0.7rem;
  border-radius: 999px;
  background: #fff6ec;
  border: 1px solid #fde3c8;
  color: #9a4a0b;
  font-size: 0.74rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  white-space: nowrap;
}

/* Softly pulsing dot signalling work in progress. */
.ml-status::before {
  content: "";
  width: 0.45rem;
  height: 0.45rem;
  border-radius: 50%;
  background: var(--buas-orange);
  animation: ml-pulse 2s ease-in-out infinite;
}

/* Available resource: a blue link instead of the pulsing "under preparation" badge. */
.ml-status-live {
  background: #eef5fa;
  border-color: #c7dcea;
  color: var(--buas-blue);
  text-decoration: none;
  transition: background-color 0.15s ease, border-color 0.15s ease;
}

.ml-status-live::before {
  display: none;
}

.ml-status-live:hover,
.ml-status-live:focus-visible {
  background: #dcebf5;
  border-color: var(--buas-blue);
  color: var(--buas-blue);
}

@keyframes ml-pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.35; }
}

@media (prefers-reduced-motion: reduce) {
  .ml-status::before {
    animation: none;
  }
}

.ml-resource-card h3 {
  font-size: 1.1rem;
  margin: 0 0 0.45rem 0;
  color: var(--ink);
}

.ml-resource-card p {
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.6;
  margin: 0;
}

.ml-sub-eyebrow {
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 850;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin: 2rem 0 0;
}

/* =========================================================
   Responsive
   ========================================================= */

@media (max-width: 1000px) {
  .ml-hero {
    grid-template-columns: 1fr;
  }

  .ml-hero-image {
    min-height: 340px;
    order: -1;
  }

  .ml-stats,
  .ml-prereq-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .ml-journey {
    grid-template-columns: repeat(2, 1fr);
  }

  .ml-tracks {
    grid-template-columns: 1fr;
    gap: 2.2rem;
  }

  .ml-quotes {
    grid-template-columns: 1fr;
  }

  .ml-quote-featured {
    grid-row: auto;
  }

  .ml-track:not(:last-child)::after {
    top: auto;
    right: auto;
    left: 50%;
    bottom: calc(-1.1rem - 0.55rem);
    transform: translateX(-50%) rotate(135deg);
  }
}

@media (max-width: 680px) {
  .ml-hero-copy {
    padding: 2rem 1.4rem;
  }

  .ml-hero-title .hero-line {
    white-space: normal;
  }

  .ml-stats,
  .ml-difference,
  .ml-model-grid,
  .ml-tracks,
  .ml-progress,
  .ml-journey,
  .ml-footer-cta,
  .ml-course-info,
  .ml-prereq-grid,
  .ml-resource-grid {
    grid-template-columns: 1fr;
  }

  .ml-course-info-item {
    border-right: 0;
    border-bottom: 1px solid var(--line);
    min-height: auto;
  }

  .ml-course-info-item:last-child {
    border-bottom: 0;
  }

  .ml-course-info-value {
    white-space: normal;
  }

  .ml-step,
  .ml-step:first-child,
  .ml-step:last-child {
    border-radius: 14px;
    border: 1px solid var(--line);
  }

  .ml-step + .ml-step {
    margin-top: 0.7rem;
  }
}

/* =========================================================
   Homepage in dark mode (body.quarto-dark is set by the sidebar toggle)
   ========================================================= */

body.quarto-dark .ml-home {
  --buas-blue: #5aaee6;
  --ink: #e3e9ef;
  --muted: #9aa8b6;
  --soft: #17212b;
  --line: #2a3744;
  --card: #141d26;
}

body.quarto-dark .ml-brand img {
  background: #ffffff;
  padding: 6px 10px;
  border-radius: 8px;
}

body.quarto-dark .ml-hero {
  background: linear-gradient(135deg, #132131 0%, #111820 60%);
  box-shadow: 0 18px 55px rgba(0, 0, 0, 0.35);
}

body.quarto-dark .ml-kicker {
  background: #13324a;
}

body.quarto-dark .ml-lead {
  color: #b5c1cd;
}

body.quarto-dark .ml-btn-secondary {
  background: var(--soft);
  border-color: #2f4152;
}

body.quarto-dark .ml-course-info,
body.quarto-dark .ml-model-card,
body.quarto-dark .ml-quote,
body.quarto-dark .ml-step,
body.quarto-dark .ml-track,
body.quarto-dark .ml-textbook,
body.quarto-dark .ml-resource-card {
  background: var(--card);
}

/* The featured quote is already dark; keep its navy panel. */
body.quarto-dark .ml-quote-featured {
  background: #102f46;
}

body.quarto-dark .ml-course-info-item.lead {
  background: #13283a;
}

body.quarto-dark .ml-diff-card .num {
  background: #0b6aa8;
}

body.quarto-dark .ml-track {
  --accent-soft: #15314a;
  box-shadow: 0 10px 26px rgba(0, 0, 0, 0.3);
}

body.quarto-dark .ml-track:nth-child(2) {
  --accent-soft: #3a2412;
}

body.quarto-dark .ml-track:nth-child(3) {
  --accent: #2bb39f;
  --accent-soft: #12342f;
}

body.quarto-dark .ml-track:not(:last-child)::after {
  border-color: #4a5866;
}

body.quarto-dark .ml-journey-item {
  background: linear-gradient(180deg, #16202a 0%, #131b23 100%);
}

body.quarto-dark .ml-note {
  background: #2a1d12;
  color: #f1d2b6;
}

body.quarto-dark .ml-resource-card {
  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.3);
}

body.quarto-dark .ml-resource-logo img[alt="GitHub"] {
  filter: invert(1);
}

body.quarto-dark .ml-resource-logo-wide {
  background: #10283a;
  border-color: #1d3f57;
}

body.quarto-dark .ml-status {
  background: #33200f;
  border-color: #5a3515;
  color: #ffb983;
}

body.quarto-dark .ml-status-live {
  background: #12293b;
  border-color: #1f4560;
  color: var(--buas-blue);
}

body.quarto-dark .ml-status-live:hover,
body.quarto-dark .ml-status-live:focus-visible {
  background: #173550;
  border-color: var(--buas-blue);
  color: var(--buas-blue);
}

/* =========================================================
   "Open in Colab" badge (injected by filters/colab-button.lua)
   ========================================================= */

.colab-launch {
  margin: 0.25rem 0 1.5rem;
}

.colab-launch img {
  display: block;
  height: 20px;
}


/* =========================================================
   Line-fitting demos (self-study/fit-demo.js)
   ========================================================= */

.fit-demo {
  --fit-surface: #ffffff;
  --fit-card: #ffffff;
  --fit-border: #e6e9ef;
  --fit-grid: #eef1f5;
  --fit-axis: #c3ccd7;
  --fit-ink: #1f2937;
  --fit-muted: #667085;
  --fit-point: #00558c;
  --fit-model: #f47a20;
  --fit-residual: rgba(244, 122, 32, 0.55);
  --fit-curve: #475467;
  --fit-track: #e6e9ef;
  --fit-good: #138a5e;
  --fit-good-soft: #e7f6ef;
  --fit-ramp: linear-gradient(90deg, #f2f8fe, #9ec5f4, #5598e7, #256abf, #184f95);

  margin: 1.5rem 0 2rem;
  padding: 1.25rem 1.25rem 1rem;
  background: var(--fit-card);
  border: 1px solid var(--fit-border);
  border-radius: 16px;
  box-shadow: 0 6px 18px rgba(16, 47, 70, 0.05);
}

body.quarto-dark .fit-demo {
  --fit-surface: #111820;
  --fit-card: #141d26;
  --fit-border: #2a3744;
  --fit-grid: #1f2a35;
  --fit-axis: #3a4856;
  --fit-ink: #e3e9ef;
  --fit-muted: #9aa8b6;
  --fit-point: #5aaee6;
  --fit-model: #f7913f;
  --fit-residual: rgba(247, 145, 63, 0.6);
  --fit-curve: #b5c1cd;
  --fit-track: #2a3744;
  --fit-good: #4cc79a;
  --fit-good-soft: #12342a;
  --fit-ramp: linear-gradient(90deg, #cde2fb, #86b6ef, #3987e5, #1c5cab, #0d366b);
  box-shadow: none;
}

.fit-plots {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.25rem;
}

@media (min-width: 720px) {
  .fit-plots-2 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.fit-panel {
  margin: 0;
  min-width: 0;
}

.fit-panel-title {
  margin: 0 0 0.35rem;
  color: var(--fit-muted);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.fit-chart {
  position: relative;
  touch-action: none;
}

.fit-svg {
  display: block;
  overflow: visible;
  position: relative;
}

.fit-svg.is-draggable {
  cursor: crosshair;
}

.fit-grid {
  stroke: var(--fit-grid);
  stroke-width: 1;
}

.fit-axis {
  stroke: var(--fit-axis);
  stroke-width: 1;
}

.fit-tick {
  fill: var(--fit-muted);
  font-size: 11px;
  font-variant-numeric: tabular-nums;
}

.fit-axis-label {
  fill: var(--fit-muted);
  font-size: 12px;
  font-style: italic;
}

.fit-point {
  fill: var(--fit-point);
  stroke: var(--fit-card);
  stroke-width: 2;
}

.fit-hit {
  fill: transparent;
  pointer-events: all;
}

.fit-line {
  stroke: var(--fit-model);
  stroke-width: 2.5;
  stroke-linecap: round;
}

.fit-residual {
  stroke: var(--fit-residual);
  stroke-width: 1.5;
}

.fit-cost-curve {
  fill: none;
  stroke: var(--fit-curve);
  stroke-width: 2;
  stroke-linejoin: round;
  stroke-linecap: round;
}

.fit-guide {
  stroke: var(--fit-model);
  stroke-width: 1;
  opacity: 0.45;
}

.fit-current {
  fill: var(--fit-model);
  stroke: var(--fit-card);
  stroke-width: 2.5;
  pointer-events: none;
}

.fit-map {
  position: absolute;
  border-radius: 2px;
}

.fit-crosshair {
  stroke: var(--fit-ink);
  stroke-width: 1;
  opacity: 0.35;
  pointer-events: none;
}

.fit-legend {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  margin-top: 0.35rem;
  color: var(--fit-muted);
  font-size: 0.75rem;
}

.fit-legend-ramp {
  width: 7rem;
  height: 0.5rem;
  border-radius: 999px;
  background: var(--fit-ramp);
}

.fit-tooltip {
  position: absolute;
  z-index: 2;
  transform: translate(12px, -50%);
  padding: 0.3rem 0.55rem;
  border-radius: 8px;
  background: var(--fit-ink);
  color: var(--fit-card);
  font-size: 0.75rem;
  white-space: nowrap;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.12s ease;
}

.fit-tooltip.is-left {
  transform: translate(calc(-100% - 12px), -50%);
}

.fit-tooltip.is-visible {
  opacity: 1;
}

/* Controls */

.fit-controls {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem 1.5rem;
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--fit-border);
}

.fit-sliders {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.75rem;
  flex: 1 1 18rem;
}

.fit-slider {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex: 1 1 14rem;
  margin: 0;
}

.fit-slider-label {
  color: var(--fit-ink);
  font-size: 0.9rem;
  font-weight: 600;
  min-width: 4.5rem;
}

.fit-slider-value {
  min-width: 2.75rem;
  color: var(--fit-ink);
  font-size: 0.9rem;
  font-variant-numeric: tabular-nums;
  text-align: right;
}

.fit-slider input[type="range"] {
  flex: 1;
  min-width: 6rem;
  height: 1.5rem;
  margin: 0;
  background: transparent;
  cursor: pointer;
  -webkit-appearance: none;
  appearance: none;
}

.fit-slider input[type="range"]::-webkit-slider-runnable-track {
  height: 4px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--fit-model) var(--fit-fill, 50%), var(--fit-track) var(--fit-fill, 50%));
}

.fit-slider input[type="range"]::-moz-range-track {
  height: 4px;
  border-radius: 999px;
  background: var(--fit-track);
}

.fit-slider input[type="range"]::-moz-range-progress {
  height: 4px;
  border-radius: 999px;
  background: var(--fit-model);
}

.fit-slider input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 18px;
  height: 18px;
  margin-top: -7px;
  border-radius: 50%;
  background: var(--fit-card);
  border: 3px solid var(--fit-model);
  box-shadow: 0 1px 4px rgba(16, 24, 40, 0.2);
  transition: transform 0.12s ease;
}

.fit-slider input[type="range"]::-moz-range-thumb {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--fit-card);
  border: 3px solid var(--fit-model);
  box-shadow: 0 1px 4px rgba(16, 24, 40, 0.2);
}

.fit-slider input[type="range"]:active::-webkit-slider-thumb {
  transform: scale(1.15);
}

.fit-slider input[type="range"]:focus-visible {
  outline: 2px solid var(--fit-model);
  outline-offset: 4px;
  border-radius: 4px;
}

.fit-readout {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem 1rem;
  color: var(--fit-ink);
  font-size: 0.9rem;
}

.fit-equation {
  font-family: var(--bs-font-monospace, monospace);
  font-size: 0.85rem;
  color: var(--fit-muted);
}

.fit-cost {
  display: inline-flex;
  align-items: baseline;
  gap: 0.4rem;
}

.fit-cost-label {
  color: var(--fit-muted);
}

.fit-cost strong {
  min-width: 3.5rem;
  font-size: 1.05rem;
  font-variant-numeric: tabular-nums;
}

.fit-badge {
  padding: 0.2rem 0.6rem;
  border-radius: 999px;
  background: var(--fit-good-soft);
  color: var(--fit-good);
  font-size: 0.8rem;
  font-weight: 700;
  opacity: 0;
  transform: scale(0.9);
  transition: opacity 0.15s ease, transform 0.15s ease;
}

.fit-badge.is-visible {
  opacity: 1;
  transform: scale(1);
}

@media (prefers-reduced-motion: reduce) {
  .fit-tooltip,
  .fit-badge,
  .fit-slider input[type="range"]::-webkit-slider-thumb {
    transition: none;
  }
}