/* ==========================================================================
   Aviation and Aerospace Medicine — Educational Specialty Stylesheet
   Dr. Ian Purcell MD PhD · Otoneurology Practice
   ========================================================================== */

.dd-aviation {
  --aviation-navy: #00253a;
  --aviation-navy-deep: #02121e;
  --aviation-teal: #036c5f;
  --aviation-teal-light: #008796;
  --aviation-teal-glow: rgba(3, 108, 95, 0.15);
  --aviation-amber: #eea676;
  --aviation-amber-dark: #c46d32;
  --aviation-cream: #fbf8f5;
  --aviation-muted: #536b76;
  --aviation-border: rgba(0, 37, 58, 0.10);
  --aviation-border-light: rgba(0, 37, 58, 0.06);
  --aviation-card-shadow: 0 10px 30px -8px rgba(0, 37, 58, 0.08), 0 2px 6px -1px rgba(0, 37, 58, 0.04);
  --aviation-card-hover-shadow: 0 20px 40px -10px rgba(0, 37, 58, 0.14), 0 4px 10px -2px rgba(0, 37, 58, 0.06);
  background: #ffffff;
  color: var(--aviation-navy);
  position: relative;
}

.dd-aviation *, 
.dd-aviation *::before, 
.dd-aviation *::after { 
  box-sizing: border-box; 
}

.dd-aviation [id] { 
  scroll-margin-top: calc(var(--dd-nav-offset, 76px) + 24px); 
}

.dd-aviation a:focus-visible { 
  outline: 3px solid var(--aviation-amber); 
  outline-offset: 4px; 
}

.dd-aviation p { 
  margin: 0 0 1.3rem; 
  font-size: 1rem; 
  line-height: 1.75; 
}

.dd-aviation h1, 
.dd-aviation h2, 
.dd-aviation h3 { 
  margin: 0; 
  color: inherit; 
}

.dd-aviation h2 { 
  font-family: var(--tr-font-display); 
  font-weight: 400; 
  font-size: clamp(2rem, 3.4vw, 3rem); 
  line-height: 1.14; 
  letter-spacing: -0.025em; 
}

.dd-aviation h3 { 
  font-size: 1.35rem; 
  font-weight: 700; 
  line-height: 1.28; 
  letter-spacing: -0.018em; 
}

.dd-aviation__container { 
  width: min(1180px, calc(100% - 64px)); 
  margin-inline: auto; 
}

.dd-aviation__skip {
  position: fixed;
  top: 12px;
  left: 16px;
  z-index: 1000;
  padding: 12px 20px;
  color: #ffffff;
  background: var(--aviation-navy);
  border: 2px solid var(--aviation-amber);
  border-radius: 6px;
  transform: translateY(-180%);
  font-weight: 600;
  text-decoration: none;
  transition: transform 0.2s ease;
}
.dd-aviation__skip:focus { 
  transform: translateY(0); 
}

/* ==========================================================================
   HERO SECTION
   ========================================================================== */
.dd-aviation__hero {
  position: relative;
  background:
    radial-gradient(1200px 600px at 85% 20%, rgba(238, 166, 118, 0.14), transparent 60%),
    radial-gradient(900px 500px at 10% 80%, rgba(3, 108, 95, 0.10), transparent 55%),
    linear-gradient(180deg, #fcfaf7 0%, #f4ede5 100%);
  padding: clamp(48px, 6vw, 76px) 0 clamp(54px, 7vw, 80px);
  border-bottom: 1px solid rgba(0, 37, 58, 0.08);
  overflow: hidden;
}

.dd-aviation__hero-bg-glow {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    radial-gradient(circle at 50% 0%, rgba(3, 108, 95, 0.04) 0%, transparent 70%),
    linear-gradient(90deg, rgba(0, 37, 58, 0.02) 1px, transparent 1px),
    linear-gradient(0deg, rgba(0, 37, 58, 0.02) 1px, transparent 1px);
  background-size: 100% 100%, 64px 64px, 64px 64px;
  opacity: 0.7;
}

.dd-aviation__hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
  gap: clamp(36px, 5vw, 68px);
  align-items: start;
  position: relative;
  z-index: 1;
}

/* Top Row: Back button & Badge */
.dd-aviation__hero-top-row {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 22px;
}

.dd-aviation__back {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  font-family: var(--tr-font-sans);
  font-size: 0.82rem;
  font-weight: 600;
  color: #485e68;
  background: rgba(255, 255, 255, 0.88);
  border: 1px solid rgba(0, 37, 58, 0.12);
  border-radius: 999px;
  text-decoration: none;
  box-shadow: 0 1px 3px rgba(0, 37, 58, 0.04);
  transition: all 0.25s cubic-bezier(0.2, 0.8, 0.2, 1);
  white-space: nowrap;
  flex-shrink: 0;
}

.dd-aviation__back-arrow {
  transition: transform 0.25s ease;
}

.dd-aviation__back:hover {
  color: var(--aviation-teal);
  background: #ffffff;
  border-color: rgba(3, 108, 95, 0.3);
  box-shadow: 0 4px 12px rgba(3, 108, 95, 0.08);
  transform: translateX(-2px);
}

.dd-aviation__back:hover .dd-aviation__back-arrow {
  transform: translateX(-3px);
}

.dd-aviation__badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: linear-gradient(135deg, rgba(3, 108, 95, 0.09), rgba(0, 164, 180, 0.12));
  border: 1px solid rgba(3, 108, 95, 0.22);
  border-radius: 999px;
  font-family: var(--tr-font-sans);
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--aviation-teal);
  box-shadow: 0 1px 3px rgba(0, 37, 58, 0.03);
  white-space: nowrap;
}

.dd-aviation__badge-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--aviation-amber);
  box-shadow: 0 0 8px var(--aviation-amber);
  animation: pulse-hud 2.5s infinite ease-in-out;
}

@keyframes pulse-hud {
  0%, 100% { transform: scale(1); opacity: 0.9; }
  50% { transform: scale(1.3); opacity: 1; }
}

/* Titles */
.dd-aviation__hero h1 {
  margin: 0 0 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.dd-aviation__title-main {
  font-family: var(--tr-font-display);
  font-size: clamp(2.85rem, 4.4vw, 4.2rem);
  font-weight: 400;
  line-height: 1.04;
  letter-spacing: -0.03em;
  color: var(--aviation-navy);
}

.dd-aviation__title-sub {
  font-family: var(--tr-font-sans);
  font-size: clamp(1.18rem, 1.8vw, 1.55rem);
  font-weight: 600;
  line-height: 1.35;
  letter-spacing: -0.015em;
  color: var(--aviation-teal);
  background: linear-gradient(90deg, #036c5f 0%, #008796 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* Conflict Card (The Core Pathology) */
.dd-aviation__conflict-card {
  position: relative;
  display: flex;
  margin: 20px 0 18px;
  background: #ffffff;
  border: 1px solid rgba(0, 37, 58, 0.10);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 4px 16px -2px rgba(0, 37, 58, 0.05);
}

.dd-aviation__conflict-accent {
  width: 5px;
  background: linear-gradient(180deg, var(--aviation-amber) 0%, var(--aviation-teal) 100%);
  flex-shrink: 0;
}

.dd-aviation__conflict-body {
  padding: 14px 18px;
}

.dd-aviation__conflict-label {
  font-family: var(--tr-font-mono);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--aviation-amber-dark);
  margin-bottom: 4px;
}

.dd-aviation__lead {
  margin: 0;
  font-family: var(--tr-font-sans);
  font-weight: 600;
  font-size: 1.12rem;
  line-height: 1.48;
  color: var(--aviation-navy);
}

.dd-aviation__summary {
  font-size: 1.02rem;
  line-height: 1.72;
  color: var(--aviation-muted);
  margin: 0 0 24px;
  max-width: 54ch;
}

/* Credential Pills */
.dd-aviation__credentials {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 28px;
}

.dd-aviation__cred-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 14px;
  background: #ffffff;
  border: 1px solid rgba(0, 37, 58, 0.10);
  border-radius: 999px;
  font-family: var(--tr-font-sans);
  font-size: 0.81rem;
  font-weight: 600;
  color: var(--aviation-navy);
  box-shadow: 0 1px 3px rgba(0, 37, 58, 0.04);
  white-space: nowrap;
}

.dd-aviation__cred-icon {
  width: 15px;
  height: 15px;
  color: var(--aviation-teal);
  flex-shrink: 0;
}

/* Action Buttons */
.dd-aviation__hero-actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}

.dd-aviation__btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 13px 26px;
  background: linear-gradient(135deg, #00253a 0%, #07384f 100%);
  color: #ffffff !important;
  border-radius: 999px;
  font-family: var(--tr-font-sans);
  font-size: 0.94rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  text-decoration: none;
  box-shadow: 0 4px 14px rgba(0, 37, 58, 0.22), 0 0 0 1px rgba(255, 255, 255, 0.1) inset;
  transition: all 0.3s cubic-bezier(0.2, 0.8, 0.2, 1);
  white-space: nowrap;
  flex-shrink: 0;
}

.dd-aviation__btn-primary:hover {
  transform: translateY(-2px);
  background: linear-gradient(135deg, #036c5f 0%, #00253a 100%);
  box-shadow: 0 8px 24px rgba(3, 108, 95, 0.3);
}

.dd-aviation__btn-arrow {
  transition: transform 0.25s ease;
}

.dd-aviation__btn-primary:hover .dd-aviation__btn-arrow {
  transform: translateY(3px);
}

.dd-aviation__btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 20px;
  background: rgba(3, 108, 95, 0.06);
  border: 1px solid rgba(3, 108, 95, 0.20);
  border-radius: 999px;
  color: var(--aviation-teal);
  font-family: var(--tr-font-sans);
  font-size: 0.88rem;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.25s ease;
  white-space: nowrap;
  flex-shrink: 0;
}

.dd-aviation__btn-secondary:hover {
  background: rgba(3, 108, 95, 0.12);
  border-color: rgba(3, 108, 95, 0.35);
  color: var(--aviation-navy);
  transform: translateX(2px);
}

/* Photo Presentation (Clean frame + caption below) */
.dd-aviation__hero-photo {
  position: relative;
  margin: 0;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.dd-aviation__photo-frame {
  position: relative;
  width: 100%;
  aspect-ratio: 4 / 3.4;
  border-radius: 18px;
  overflow: hidden;
  background: #00253a;
  box-shadow:
    0 20px 50px -12px rgba(0, 37, 58, 0.28),
    0 0 0 1px rgba(0, 37, 58, 0.08);
}

.dd-aviation__photo-frame img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 32%;
  transition: transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

.dd-aviation__hero-photo:hover .dd-aviation__photo-frame img {
  transform: scale(1.025);
}

.dd-aviation__photo-hud-badge {
  position: absolute;
  top: 14px;
  left: 14px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 13px;
  background: rgba(0, 37, 58, 0.86);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.20);
  border-radius: 999px;
  color: #f6fbfc;
  font-family: var(--tr-font-sans);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.dd-aviation__hud-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #6ee7b7;
  box-shadow: 0 0 8px #6ee7b7;
}

/* Glass Caption (Positioned beneath photo as a refined editorial card) */
.dd-aviation__glass-caption {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 16px 20px;
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(0, 37, 58, 0.10);
  border-radius: 14px;
  color: var(--aviation-navy);
  box-shadow: 0 8px 24px -4px rgba(0, 37, 58, 0.08);
}

.dd-aviation__caption-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.dd-aviation__caption-badge {
  font-family: var(--tr-font-sans);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--aviation-amber-dark);
}

.dd-aviation__caption-coords {
  font-family: var(--tr-font-mono);
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.10em;
  color: #6a808a;
}

.dd-aviation__caption-text {
  margin: 0 !important;
  font-size: 0.88rem;
  line-height: 1.55;
  color: var(--aviation-muted);
}

.dd-aviation__caption-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 4px;
  font-family: var(--tr-font-sans);
  font-size: 0.84rem;
  font-weight: 600;
  color: var(--aviation-teal);
  text-decoration: none;
  border-bottom: 1px solid rgba(3, 108, 95, 0.35);
  padding-bottom: 2px;
  width: fit-content;
  transition: all 0.2s ease;
}

.dd-aviation__caption-link:hover {
  color: var(--aviation-navy);
  border-color: var(--aviation-navy);
  transform: translateX(2px);
}

/* ==========================================================================
   TABLE OF CONTENTS RIBBON (01-05 NAVIGATION)
   ========================================================================== */
.dd-aviation__contents {
  background: #ffffff;
  border-bottom: 1px solid rgba(0, 37, 58, 0.09);
  box-shadow: 0 4px 16px -4px rgba(0, 37, 58, 0.05);
  position: sticky;
  top: var(--dd-nav-offset, 76px);
  z-index: 90;
}

.dd-aviation__contents-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 6px;
  padding: 6px 0;
}

.dd-aviation__toc-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  text-decoration: none;
  color: var(--aviation-navy);
  border-radius: 8px;
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

.dd-aviation__toc-item:hover {
  background: rgba(3, 108, 95, 0.07);
  color: var(--aviation-teal);
  transform: translateY(-1px);
}

.dd-aviation__toc-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  border-radius: 6px;
  background: rgba(3, 108, 95, 0.09);
  color: var(--aviation-teal);
  font-family: var(--tr-font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  flex-shrink: 0;
  transition: all 0.2s ease;
}

.dd-aviation__toc-item:hover .dd-aviation__toc-num {
  background: var(--aviation-teal);
  color: #ffffff;
}

.dd-aviation__toc-label {
  font-family: var(--tr-font-sans);
  font-size: 0.86rem;
  font-weight: 600;
  line-height: 1.25;
  white-space: nowrap;
}

/* ==========================================================================
   SECTIONS GENERAL
   ========================================================================== */
.dd-aviation__section { 
  padding: clamp(64px, 8vw, 96px) 0; 
}

.dd-aviation__section--soft { 
  background: var(--aviation-cream); 
}

.dd-aviation__section--dark { 
  background: var(--aviation-navy-deep); 
  color: #ffffff; 
}

.dd-aviation__section-heading {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(32px, 6vw, 88px);
  align-items: end;
  margin-bottom: 44px;
}

.dd-aviation__section-heading > p {
  margin: 0;
  color: var(--aviation-muted);
  font-size: 1.05rem;
  line-height: 1.75;
}

.dd-aviation__eyebrow {
  margin: 0 0 14px;
  font-family: var(--tr-font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--aviation-teal);
}

.dd-aviation__section--dark .dd-aviation__eyebrow {
  color: var(--aviation-amber);
}

.dd-aviation__citation {
  color: var(--aviation-teal);
  font-size: 0.82rem;
  white-space: nowrap;
  text-decoration: none;
  font-weight: 700;
  margin-left: 2px;
}

.dd-aviation__citation:hover {
  text-decoration: underline;
}

.dd-aviation__section--dark .dd-aviation__citation {
  color: var(--aviation-amber);
}

.dd-aviation__text-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--aviation-teal);
  font-family: var(--tr-font-sans);
  font-weight: 600;
  font-size: 0.95rem;
  line-height: 1.6;
  text-decoration: none;
  border-bottom: 1px solid rgba(3, 108, 95, 0.35);
  padding-bottom: 2px;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.dd-aviation__text-link:hover {
  color: var(--aviation-navy);
  border-color: var(--aviation-navy);
  transform: translateX(2px);
}

/* ==========================================================================
   SECTION 01: THE SENSORY SYSTEM (#understanding)
   ========================================================================== */
.dd-aviation__senses {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.dd-aviation__sense {
  display: flex;
  flex-direction: column;
  padding: 30px 26px;
  background: #ffffff;
  border: 1px solid rgba(0, 37, 58, 0.09);
  border-radius: 14px;
  box-shadow: 0 4px 20px rgba(0, 37, 58, 0.05);
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}

.dd-aviation__sense:hover {
  transform: translateY(-3px);
  border-color: rgba(3, 108, 95, 0.3);
  box-shadow: 0 14px 32px rgba(0, 37, 58, 0.09);
}

.dd-aviation__sense-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border-radius: 10px;
  background: rgba(3, 108, 95, 0.09);
  color: var(--aviation-teal);
  font-family: var(--tr-font-mono);
  font-size: 0.88rem;
  font-weight: 700;
  margin-bottom: 20px;
}

.dd-aviation__sense h3 {
  margin-bottom: 10px;
  font-size: 1.30rem;
  font-weight: 700;
  color: var(--aviation-navy);
}

.dd-aviation__sense p {
  margin: 0;
  font-size: 0.95rem;
  line-height: 1.70;
  color: var(--aviation-muted);
}

.dd-aviation .dd-aviation__takeaway {
  margin: 36px 0 0;
  padding: 22px 28px;
  border-radius: 12px;
  border-left: 4px solid var(--aviation-teal);
  background: linear-gradient(90deg, rgba(3, 108, 95, 0.07) 0%, rgba(3, 108, 95, 0.02) 100%);
  border-top: 1px solid rgba(3, 108, 95, 0.12);
  border-right: 1px solid rgba(3, 108, 95, 0.12);
  border-bottom: 1px solid rgba(3, 108, 95, 0.12);
  font-size: 0.98rem;
  line-height: 1.7;
  color: var(--aviation-navy);
}

.dd-aviation__takeaway strong {
  font-weight: 700;
  color: var(--aviation-teal);
}

/* ==========================================================================
   SECTION 02: IN FLIGHT ILLUSIONS (#flight-illusions)
   ========================================================================== */
.dd-aviation__illusions-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.82fr) minmax(0, 1.18fr);
  gap: clamp(40px, 6vw, 84px);
  align-items: start;
}

.dd-aviation__illusions-intro h2 {
  margin-bottom: 22px;
}

.dd-aviation__illusions-intro > p:not(.dd-aviation__eyebrow) {
  color: var(--aviation-muted);
  font-size: 1.05rem;
  line-height: 1.72;
  margin-bottom: 24px;
}

.dd-aviation__illusions-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.dd-aviation__illusion {
  display: grid;
  grid-template-columns: 46px 1fr;
  gap: 20px;
  padding: 24px 26px;
  background: #ffffff;
  border: 1px solid rgba(0, 37, 58, 0.09);
  border-radius: 14px;
  box-shadow: 0 4px 16px rgba(0, 37, 58, 0.04);
  transition: all 0.25s ease;
}

.dd-aviation__illusion:hover {
  transform: translateX(4px);
  border-color: rgba(3, 108, 95, 0.28);
  box-shadow: 0 8px 24px rgba(0, 37, 58, 0.08);
}

.dd-aviation__illusion-index {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  background: linear-gradient(135deg, rgba(3, 108, 95, 0.12) 0%, rgba(0, 135, 150, 0.08) 100%);
  border: 1px solid rgba(3, 108, 95, 0.20);
  border-radius: 10px;
  font-family: var(--tr-font-mono);
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--aviation-teal);
  flex-shrink: 0;
}

.dd-aviation__illusion h3 {
  margin: 0 0 6px;
  font-size: 1.22rem;
  font-weight: 700;
  color: var(--aviation-navy);
}

.dd-aviation__illusion p {
  margin: 0;
  font-size: 0.95rem;
  line-height: 1.65;
  color: var(--aviation-muted);
}

/* ==========================================================================
   SECTION 03: HUMAN × AIRCRAFT (See also vestibular-cockpit.css)
   ========================================================================== */
.dd-aviation__dark-lead {
  color: #e4eef2;
  font-family: var(--tr-font-sans);
  font-size: 1.15rem;
  line-height: 1.68;
}

/* ==========================================================================
   COMPACT AUTO-ORBITING GOGGLES 360 (#goggles-360)
   ========================================================================== */
.dd-aviation-orbit {
  position: relative;
  overflow: hidden;
}

.dd-aviation-orbit::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 70% 55% at 70% 40%, rgba(85, 213, 197, 0.12), transparent 70%),
    radial-gradient(circle 420px at 12% 80%, rgba(240, 172, 127, 0.06), transparent 60%);
  pointer-events: none;
}

.dd-aviation-orbit__layout {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: clamp(28px, 5vw, 60px);
  align-items: center;
}

.dd-aviation-orbit__copy h2 {
  max-width: 14ch;
  margin-bottom: 18px;
  color: #ffffff;
  font-family: var(--tr-font-display);
  font-weight: 400;
  font-size: clamp(2rem, 3.2vw, 2.7rem);
  line-height: 1.14;
}

.dd-aviation-orbit__copy p:not(.dd-aviation__eyebrow) {
  max-width: 44ch;
  margin-bottom: 22px;
  color: #c5d4db;
  font-size: 1.02rem;
  line-height: 1.72;
}

.dd-aviation-orbit__stage {
  margin: 0;
  border: 1px solid rgba(62, 172, 184, 0.25);
  border-radius: 14px;
  overflow: hidden;
  background: #06111a;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
}

.dd-aviation-orbit__viewport {
  position: relative;
  width: 100%;
  aspect-ratio: 4 / 3;
  min-height: 320px;
  overflow: hidden;
  background:
    radial-gradient(ellipse 60% 50% at 50% 45%, rgba(85, 213, 197, 0.12), transparent 70%),
    linear-gradient(180deg, #0a1b28 0%, #06111a 100%);
}

.dd-aviation-orbit__track {
  position: absolute;
  inset: 0;
  z-index: 1;
}

.dd-aviation-orbit__slide {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
  opacity: 0;
  transform: scale(1.04);
  transition: opacity 1.1s ease, transform 4.2s ease;
  pointer-events: none;
}

.dd-aviation-orbit__slide.is-active {
  opacity: 1;
  transform: scale(1);
  z-index: 2;
}

.dd-aviation-orbit__viewport canvas {
  display: none;
}

.dd-aviation-orbit__fallback {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  position: absolute;
  inset: 0;
  z-index: 0;
}

.dd-aviation-orbit__viewport.is-ready .dd-aviation-orbit__fallback {
  display: none;
}

.dd-aviation-orbit__viewport.is-fallback .dd-aviation-orbit__track {
  display: none;
}

.dd-aviation-orbit__viewport.is-fallback .dd-aviation-orbit__fallback {
  display: block;
  position: relative;
}

@media (prefers-reduced-motion: reduce) {
  .dd-aviation-orbit__slide {
    transition: opacity 0.4s ease;
    transform: none;
  }
  .dd-aviation-orbit__slide.is-active {
    transform: none;
  }
}

.dd-aviation-orbit__stage figcaption {
  padding: 12px 18px 14px;
  color: #9eb9c3;
  font: 500 0.70rem/1.45 var(--tr-font-mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

/* ==========================================================================
   SECTION 04: IN THE FIELD (#field)
   ========================================================================== */
.dd-aviation__field-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.90fr) minmax(0, 1.10fr);
  gap: clamp(32px, 5vw, 64px);
  align-items: start;
  margin-top: 36px;
}

.dd-aviation__field-photo {
  margin: 0;
  position: sticky;
  top: calc(var(--dd-nav-offset, 76px) + 36px);
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.dd-aviation__field-photo img {
  width: 100%;
  aspect-ratio: 4 / 4.6;
  max-height: 540px;
  object-fit: cover;
  object-position: top center;
  display: block;
  border-radius: 16px;
  border: 1px solid rgba(0, 37, 58, 0.10);
  box-shadow: 
    0 16px 40px -12px rgba(0, 37, 58, 0.18),
    0 2px 6px rgba(0, 37, 58, 0.04);
}

.dd-aviation__field-photo figcaption {
  padding: 12px 18px;
  background: #ffffff;
  border: 1px solid rgba(0, 37, 58, 0.09);
  border-radius: 12px;
  font-family: var(--tr-font-sans);
  font-size: 0.84rem;
  font-weight: 500;
  color: var(--aviation-muted);
  line-height: 1.5;
  box-shadow: 0 4px 14px rgba(0, 37, 58, 0.04);
}

.dd-aviation__field-notes {
  display: grid;
  gap: 16px;
}

.dd-aviation__field-notes article {
  padding: 24px 26px;
  background: #ffffff;
  border: 1px solid rgba(0, 37, 58, 0.09);
  border-radius: 14px;
  box-shadow: 0 4px 16px rgba(0, 37, 58, 0.04);
  transition: all 0.25s ease;
}

.dd-aviation__field-notes article:hover {
  transform: translateY(-2px);
  border-color: rgba(3, 108, 95, 0.25);
  box-shadow: 0 10px 28px rgba(0, 37, 58, 0.08);
}

.dd-aviation__field-notes h3 {
  margin: 0 0 10px;
  font-size: 1.18rem;
  font-weight: 700;
  color: var(--aviation-navy);
  line-height: 1.35;
}

.dd-aviation__field-notes p {
  margin: 0;
  font-size: 0.94rem;
  line-height: 1.68;
  color: var(--aviation-muted);
}

.dd-aviation__field-notes .dd-aviation__text-link {
  margin-top: 14px;
}

/* Research Pathway Cards */
.dd-research-path {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
  margin-top: 48px;
  padding-top: 36px;
  border-top: 1px solid rgba(0, 37, 58, 0.12);
}

.dd-research-path a {
  display: flex;
  flex-direction: column;
  padding: 26px;
  background: #ffffff;
  border: 1px solid rgba(0, 37, 58, 0.09);
  border-radius: 14px;
  color: var(--aviation-navy);
  text-decoration: none;
  box-shadow: 0 4px 16px rgba(0, 37, 58, 0.04);
  transition: all 0.25s ease;
}

.dd-research-path a:hover {
  transform: translateY(-3px);
  border-color: var(--aviation-teal);
  box-shadow: 0 14px 34px rgba(3, 108, 95, 0.12);
}

.dd-research-path span {
  display: block;
  color: var(--aviation-teal);
  font: 700 0.72rem/1.5 var(--tr-font-mono);
  text-transform: uppercase;
  letter-spacing: 0.14em;
  margin-bottom: 10px;
}

.dd-research-path strong {
  font-family: var(--tr-font-display);
  font-weight: 400;
  font-size: 1.38rem;
  line-height: 1.25;
  color: var(--aviation-navy);
}

.dd-research-path p {
  margin: 10px 0 0;
  font-size: 0.92rem;
  line-height: 1.65;
  color: var(--aviation-muted);
}

/* ==========================================================================
   SECTION 05: CLINICAL PERSPECTIVE (#evaluation)
   ========================================================================== */
.dd-aviation__care-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 36px;
}

.dd-aviation__care-link {
  display: flex;
  flex-direction: column;
  border: 1px solid rgba(0, 37, 58, 0.10);
  border-top: 3px solid rgba(3, 108, 95, 0.35);
  border-radius: 16px;
  text-decoration: none;
  color: inherit;
  background: #ffffff;
  overflow: hidden;
  box-shadow: 0 4px 20px rgba(0, 37, 58, 0.05);
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.dd-aviation__care-link:hover {
  transform: translateY(-4px);
  border-color: rgba(3, 108, 95, 0.3);
  border-top-color: var(--aviation-teal);
  box-shadow: 0 16px 40px rgba(0, 37, 58, 0.10);
}

.dd-aviation__care-media {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 10;
  overflow: hidden;
  background: #02090e;
  position: relative;
}

.dd-aviation__care-media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.dd-aviation__care-link:hover .dd-aviation__care-media img {
  transform: scale(1.04);
}

.dd-aviation__care-kicker {
  margin: 22px 24px 10px;
  color: var(--aviation-teal);
  font-family: var(--tr-font-mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-weight: 700;
}

.dd-aviation__care-link h3 {
  margin: 0 24px 10px;
  font-size: 1.28rem;
  font-weight: 700;
  color: var(--aviation-navy);
}

.dd-aviation__care-link p {
  margin: 0 24px 24px;
  font-size: 0.92rem;
  line-height: 1.70;
  color: var(--aviation-muted);
}

.dd-aviation__care-action {
  width: calc(100% - 48px);
  margin: auto 24px 22px;
  padding-top: 16px;
  border-top: 1px solid rgba(0, 37, 58, 0.08);
  font-family: var(--tr-font-sans);
  color: var(--aviation-teal);
  font-weight: 700;
  font-size: 0.88rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  white-space: nowrap;
}

.dd-aviation__care-action span {
  transition: transform 0.2s ease;
}

.dd-aviation__care-link:hover .dd-aviation__care-action span {
  transform: translateX(3px);
}

/* Aeromedical Safety Advisory */
.dd-aviation__safety {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 40px;
  margin-top: 56px;
  padding: 38px 42px;
  border-radius: 18px;
  border: 1px solid rgba(0, 37, 58, 0.12);
  background: linear-gradient(135deg, #ffffff 0%, #f7f9f8 100%);
  box-shadow: 0 12px 36px rgba(0, 37, 58, 0.06);
}

.dd-aviation__safety .dd-aviation__eyebrow {
  margin-bottom: 12px;
  color: var(--aviation-amber-dark);
}

.dd-aviation__safety h3 {
  font-family: var(--tr-font-display);
  font-size: 2.1rem;
  font-weight: 400;
  line-height: 1.15;
  color: var(--aviation-navy);
}

.dd-aviation__safety p {
  color: var(--aviation-muted);
  font-size: 0.95rem;
  line-height: 1.75;
}

.dd-aviation__safety .dd-aviation__text-link {
  font-size: 0.92rem;
  font-weight: 700;
  margin-top: 12px;
  white-space: nowrap;
}

/* ==========================================================================
   SOURCES & GUIDANCE DIRECTORY (#sources)
   ========================================================================== */
.dd-aviation__sources {
  padding: 56px 0 64px;
  background: #f4f7f6;
  border-top: 1px solid rgba(0, 37, 58, 0.08);
}

.dd-aviation__sources-grid {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 60px;
}

.dd-aviation__sources .dd-aviation__eyebrow {
  margin-bottom: 12px;
}

.dd-aviation__sources h2 {
  font-family: var(--tr-font-sans);
  font-size: 1.45rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--aviation-navy);
}

.dd-aviation__sources p {
  color: var(--aviation-muted);
  font-size: 0.90rem;
  margin: 0;
  line-height: 1.6;
}

.dd-aviation__sources ol {
  display: grid;
  gap: 12px;
  padding-left: 20px;
  margin: 0;
}

.dd-aviation__sources li {
  font-size: 0.88rem;
  line-height: 1.6;
  color: var(--aviation-teal);
}

.dd-aviation__sources li a {
  color: var(--aviation-navy);
  text-decoration: none;
  border-bottom: 1px solid rgba(0, 37, 58, 0.18);
  transition: all 0.2s ease;
}

.dd-aviation__sources li a:hover {
  color: var(--aviation-teal);
  border-color: var(--aviation-teal);
}

/* ==========================================================================
   RESPONSIVE BREAKPOINTS
   ========================================================================== */
@media (max-width: 991px) {
  .dd-aviation__container { width: calc(100% - 48px); }
  .dd-aviation__hero { padding: 40px 0 48px; }
  .dd-aviation__hero-grid { grid-template-columns: 1fr; gap: 36px; }
  .dd-aviation__photo-frame { aspect-ratio: 16 / 10; max-height: 480px; }
  .dd-aviation__title-main { font-size: 3.2rem; }
  .dd-aviation__title-sub { font-size: 1.25rem; }
  .dd-aviation__contents-grid { grid-template-columns: repeat(3, 1fr); }
  .dd-aviation__section { padding: 64px 0; }
  .dd-aviation__senses { grid-template-columns: 1fr; gap: 18px; }
  .dd-aviation__illusions-grid { grid-template-columns: 1fr; gap: 32px; }
  .dd-aviation-orbit__layout { grid-template-columns: 1fr; gap: 28px; }
  .dd-aviation__field-grid { grid-template-columns: 1fr; gap: 32px; }
  .dd-aviation__field-photo { position: static; max-width: 520px; }
  .dd-research-path { grid-template-columns: 1fr; gap: 14px; }
  .dd-aviation__care-grid { grid-template-columns: 1fr; gap: 18px; }
  .dd-aviation__safety { grid-template-columns: 1fr; padding: 30px; gap: 24px; }
  .dd-aviation__sources-grid { grid-template-columns: 1fr; gap: 30px; }
}

@media (max-width: 767px) {
  .dd-aviation__container { width: calc(100% - 36px); }
  .dd-aviation__title-main { font-size: clamp(2.4rem, 8vw, 3.2rem); }
  .dd-aviation__title-sub { font-size: 1.15rem; }
  .dd-aviation__contents-grid { grid-template-columns: repeat(2, 1fr); gap: 6px; }
  .dd-aviation__toc-item { padding: 8px 10px; }
  .dd-aviation__section-heading { grid-template-columns: 1fr; gap: 16px; margin-bottom: 28px; }
  .dd-aviation__section-heading h2 br { display: none; }
  .dd-aviation__illusion { grid-template-columns: 38px 1fr; gap: 14px; padding: 18px 16px; }
  .dd-aviation__illusion-index { width: 38px; height: 38px; font-size: 0.82rem; }
  .dd-aviation-orbit__viewport { min-height: 260px; }
}

@media (max-width: 480px) {
  .dd-aviation__hero-top-row { gap: 8px; }
  .dd-aviation__hero-actions { flex-direction: column; align-items: stretch; }
  .dd-aviation__btn-primary, 
  .dd-aviation__btn-secondary { justify-content: center; width: 100%; }
  .dd-aviation__contents-grid { grid-template-columns: 1fr; }
  .dd-aviation__safety { padding: 24px 20px; }
}

@media (prefers-reduced-motion: reduce) {
  .dd-aviation *,
  .dd-aviation *::before,
  .dd-aviation *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}