/* ═══════════════════════════════════════════════
   CARDIOVASCULAR SYSTEM PRESENTATION
   Design: Alpine Frost × Medical Editorial
   Fonts: Playfair Display + Plus Jakarta Sans
═══════════════════════════════════════════════ */

:root {
  --navy-deep:   #0A1929;
  --navy-mid:    #0D2137;
  --navy:        #2E5090;
  --blue-light:  #A8C4E0;
  --frost:       #E3EDF7;
  --white:       #FFFFFF;
  --red-heart:   #C0392B;
  --red-light:   #E74C3C;
  --teal:        #1ABC9C;
  --gold:        #F39C12;
  --text-dark:   #0A1929;
  --text-mid:    #2C3E50;
  --text-light:  rgba(255,255,255,0.85);
  --text-muted:  rgba(255,255,255,0.55);

  --font-display: 'Playfair Display', Georgia, serif;
  --font-body:    'Plus Jakarta Sans', sans-serif;

  --slide-w: 100vw;
  --slide-h: 100vh;
  --ease:    cubic-bezier(0.4, 0, 0.2, 1);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  width: 100%; height: 100%;
  overflow: hidden;
  background: var(--navy-deep);
  font-family: var(--font-body);
  -webkit-font-smoothing: antialiased;
}

/* ── Progress Bar ─────────────────────────────── */
.progress-bar {
  position: fixed; top: 0; left: 0; z-index: 100;
  height: 3px;
  background: linear-gradient(90deg, var(--red-heart), var(--red-light), var(--gold));
  width: 20%;
  transition: width 0.5s var(--ease);
  box-shadow: 0 0 12px rgba(192,57,43,0.6);
}

/* ── Slide Counter ────────────────────────────── */
.slide-counter {
  position: fixed; top: 24px; right: 80px; z-index: 100;
  font-family: var(--font-body);
  font-size: 13px; font-weight: 600;
  color: rgba(255,255,255,0.5);
  letter-spacing: 0.1em;
}
.slide-counter .divider { margin: 0 4px; opacity: 0.4; }

/* ── Dot Navigation ───────────────────────────── */
.dot-nav {
  position: fixed; bottom: 32px; left: 50%; transform: translateX(-50%);
  z-index: 100;
  display: flex; gap: 10px; align-items: center;
}
.dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: rgba(255,255,255,0.25);
  border: none; cursor: pointer;
  transition: all 0.3s var(--ease);
  padding: 0;
}
.dot.active {
  background: var(--white);
  width: 28px; border-radius: 4px;
  box-shadow: 0 0 8px rgba(255,255,255,0.4);
}
.dot:hover:not(.active) { background: rgba(255,255,255,0.5); }

/* ── Arrow Navigation ─────────────────────────── */
.nav-arrow {
  position: fixed; top: 50%; transform: translateY(-50%);
  z-index: 100;
  width: 48px; height: 48px; border-radius: 50%;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.15);
  color: rgba(255,255,255,0.7);
  cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  transition: all 0.25s var(--ease);
  backdrop-filter: blur(8px);
}
.nav-arrow svg { width: 20px; height: 20px; }
.nav-arrow:hover {
  background: rgba(255,255,255,0.18);
  color: var(--white);
  border-color: rgba(255,255,255,0.35);
}
.nav-arrow:disabled { opacity: 0.2; pointer-events: none; }
.nav-prev { left: 24px; }
.nav-next { right: 24px; }

/* ── Slides Wrapper ───────────────────────────── */
.slides-wrapper {
  width: 100vw; height: 100vh;
  position: relative;
}

/* ── Base Slide ───────────────────────────────── */
.slide {
  position: absolute; inset: 0;
  width: 100vw; height: 100vh;
  display: flex; align-items: center; justify-content: center;
  opacity: 0;
  transform: translateX(60px);
  transition: opacity 0.6s var(--ease), transform 0.6s var(--ease);
  pointer-events: none;
  overflow: hidden;
}
.slide.active {
  opacity: 1; transform: translateX(0);
  pointer-events: all;
}
.slide.exit {
  opacity: 0; transform: translateX(-60px);
}

/* ── Background Layers ────────────────────────── */
.slide-bg {
  position: absolute; inset: 0; z-index: 0;
}
.bg-img {
  width: 100%; height: 100%;
  object-fit: cover; object-position: center;
  display: block;
}
.bg-overlay {
  position: absolute; inset: 0;
}
.overlay-dark  { background: linear-gradient(135deg, rgba(10,25,41,0.88) 0%, rgba(10,25,41,0.72) 60%, rgba(46,80,144,0.5) 100%); }
.overlay-blue  { background: linear-gradient(135deg, rgba(10,25,41,0.92) 0%, rgba(13,33,55,0.85) 50%, rgba(46,80,144,0.6) 100%); }
.overlay-green { background: linear-gradient(135deg, rgba(10,25,41,0.90) 0%, rgba(13,55,40,0.80) 60%, rgba(26,188,156,0.3) 100%); }

.bg-solid { position: absolute; inset: 0; }
.bg-navy  { background: linear-gradient(145deg, #0A1929 0%, #0D2137 50%, #112240 100%); }
.bg-dark  { background: linear-gradient(145deg, #080E18 0%, #0A1929 60%, #0D2137 100%); }

.bg-grid {
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(168,196,224,0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(168,196,224,0.04) 1px, transparent 1px);
  background-size: 60px 60px;
}
.bg-accent-circle {
  position: absolute;
  width: 600px; height: 600px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(46,80,144,0.25) 0%, transparent 70%);
  right: -100px; top: 50%; transform: translateY(-50%);
}
.bg-pattern {
  position: absolute; inset: 0;
  background-image: radial-gradient(rgba(168,196,224,0.06) 1px, transparent 1px);
  background-size: 32px 32px;
}

/* ── Slide Content ────────────────────────────── */
.slide-content {
  position: relative; z-index: 1;
  width: 100%; max-width: 1200px;
  padding: 60px 80px;
}

/* ── Section Label ────────────────────────────── */
.section-label {
  font-family: var(--font-body);
  font-size: 11px; font-weight: 700;
  letter-spacing: 0.25em; text-transform: uppercase;
  color: var(--blue-light);
  margin-bottom: 16px;
  display: flex; align-items: center; gap: 10px;
}
.section-label::before {
  content: '';
  display: inline-block;
  width: 24px; height: 2px;
  background: var(--blue-light);
}
.section-label.light { color: rgba(255,255,255,0.6); }
.section-label.light::before { background: rgba(255,255,255,0.4); }

/* ── Slide Titles ─────────────────────────────── */
.slide-title {
  font-family: var(--font-display);
  font-size: clamp(36px, 5vw, 58px);
  font-weight: 700;
  line-height: 1.1;
  color: var(--white);
  margin-bottom: 20px;
}
.slide-title em {
  font-style: italic;
  color: var(--blue-light);
}
.slide-title.light { color: var(--white); }

.slide-desc {
  font-size: 15px; line-height: 1.75;
  color: rgba(255,255,255,0.7);
  max-width: 520px;
  margin-bottom: 32px;
}
.slide-desc.light { color: rgba(255,255,255,0.75); }

/* ════════════════════════════════════════════════
   SLIDE 1 — HERO LAYOUT
════════════════════════════════════════════════ */
.layout-hero {
  display: flex; flex-direction: column;
  justify-content: center;
  min-height: 80vh;
  padding-top: 80px;
}

.hero-badge {
  display: inline-flex; align-items: center;
  font-size: 11px; font-weight: 700;
  letter-spacing: 0.2em; text-transform: uppercase;
  color: var(--red-light);
  border: 1px solid rgba(231,76,60,0.4);
  padding: 6px 16px; border-radius: 20px;
  margin-bottom: 28px;
  width: fit-content;
  background: rgba(231,76,60,0.08);
}

.hero-title {
  font-family: var(--font-display);
  font-size: clamp(52px, 7vw, 88px);
  font-weight: 900;
  line-height: 1.0;
  color: var(--white);
  margin-bottom: 28px;
  letter-spacing: -0.02em;
}
.hero-title em {
  font-style: italic;
  color: var(--blue-light);
  display: block;
}

.hero-subtitle {
  font-size: 17px; line-height: 1.7;
  color: rgba(255,255,255,0.65);
  max-width: 580px;
  margin-bottom: 52px;
}

.hero-stats {
  display: flex; align-items: center; gap: 0;
  margin-bottom: 48px;
}
.stat-item {
  display: flex; flex-direction: column; gap: 4px;
  padding: 0 36px;
}
.stat-item:first-child { padding-left: 0; }
.stat-num {
  font-family: var(--font-display);
  font-size: 32px; font-weight: 700;
  color: var(--white);
  line-height: 1;
}
.stat-label {
  font-size: 11px; font-weight: 500;
  color: rgba(255,255,255,0.45);
  letter-spacing: 0.08em; text-transform: uppercase;
}
.stat-divider {
  width: 1px; height: 48px;
  background: rgba(255,255,255,0.15);
}

.slide-tag {
  font-size: 11px; font-weight: 600;
  letter-spacing: 0.15em; text-transform: uppercase;
  color: rgba(255,255,255,0.3);
}

/* ════════════════════════════════════════════════
   SLIDE 2 — SPLIT LAYOUT
════════════════════════════════════════════════ */
.layout-split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.feature-list {
  display: flex; flex-direction: column; gap: 16px;
}
.feature-item {
  display: flex; align-items: flex-start; gap: 16px;
  padding: 14px 18px;
  background: rgba(255,255,255,0.04);
  border: 1px solid rgba(255,255,255,0.07);
  border-radius: 10px;
  transition: background 0.2s;
}
.feature-item:hover { background: rgba(255,255,255,0.07); }
.feature-icon {
  font-size: 20px; min-width: 32px;
  display: flex; align-items: center; justify-content: center;
}
.feature-item strong {
  display: block;
  font-size: 14px; font-weight: 700;
  color: var(--white);
  margin-bottom: 2px;
}
.feature-item span {
  font-size: 12px; color: rgba(255,255,255,0.5);
  line-height: 1.5;
}

.image-frame {
  position: relative;
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid rgba(168,196,224,0.15);
  background: rgba(255,255,255,0.95);
  padding: 20px;
  box-shadow: 0 32px 80px rgba(0,0,0,0.4);
}
.slide-img {
  width: 100%; height: auto;
  display: block;
  border-radius: 8px;
}
.image-caption {
  margin-top: 12px;
  font-size: 11px; line-height: 1.5;
  color: #666;
  text-align: center;
  font-style: italic;
}

/* ════════════════════════════════════════════════
   SLIDE 3 — CENTERED LAYOUT
════════════════════════════════════════════════ */
.layout-centered {
  display: flex; flex-direction: column;
  align-items: center; text-align: center;
  padding: 48px 80px;
}
.layout-centered .slide-title { text-align: center; }
.layout-centered .slide-desc { text-align: center; max-width: 640px; }

.circuit-cards {
  display: grid; grid-template-columns: 1fr 1fr;
  gap: 24px; width: 100%;
  margin-bottom: 28px;
}
.circuit-card {
  padding: 28px 28px 24px;
  border-radius: 14px;
  border: 1px solid rgba(255,255,255,0.1);
  text-align: left;
  backdrop-filter: blur(12px);
  transition: transform 0.25s var(--ease);
}
.circuit-card:hover { transform: translateY(-3px); }
.card-pulmonary {
  background: linear-gradient(135deg, rgba(46,80,144,0.35), rgba(46,80,144,0.15));
  border-color: rgba(168,196,224,0.2);
}
.card-systemic {
  background: linear-gradient(135deg, rgba(192,57,43,0.3), rgba(192,57,43,0.12));
  border-color: rgba(231,76,60,0.2);
}
.circuit-icon { font-size: 28px; margin-bottom: 10px; }
.circuit-card h3 {
  font-family: var(--font-display);
  font-size: 20px; font-weight: 700;
  color: var(--white); margin-bottom: 10px;
}
.circuit-card p {
  font-size: 13px; line-height: 1.65;
  color: rgba(255,255,255,0.65);
  margin-bottom: 16px;
}
.circuit-flow {
  display: flex; flex-wrap: wrap; align-items: center; gap: 6px;
  font-size: 11px; font-weight: 600;
  color: rgba(255,255,255,0.5);
  letter-spacing: 0.05em;
}
.circuit-flow span { color: rgba(255,255,255,0.7); }
.circuit-flow .arrow { color: rgba(255,255,255,0.3); font-size: 14px; }

.vessel-types {
  display: flex; gap: 32px; align-items: center;
  flex-wrap: wrap; justify-content: center;
}
.vessel-item {
  display: flex; align-items: center; gap: 8px;
  font-size: 13px; color: rgba(255,255,255,0.65);
}
.vessel-dot {
  width: 10px; height: 10px; border-radius: 50%;
}
.dot-red   { background: #E74C3C; box-shadow: 0 0 6px rgba(231,76,60,0.5); }
.dot-blue  { background: #3498DB; box-shadow: 0 0 6px rgba(52,152,219,0.5); }
.dot-pink  { background: #E91E8C; box-shadow: 0 0 6px rgba(233,30,140,0.4); }

/* ════════════════════════════════════════════════
   SLIDE 4 — FULL LAYOUT (DISEASES)
════════════════════════════════════════════════ */
.layout-full {
  width: 100%; max-width: 1200px;
  padding: 48px 80px;
}
.layout-full .slide-title { margin-bottom: 12px; }
.layout-full .slide-desc { margin-bottom: 28px; font-size: 14px; }

.disease-grid {
  display: grid; grid-template-columns: repeat(4, 1fr);
  gap: 16px; margin-bottom: 28px;
}
.disease-card {
  padding: 22px 20px;
  background: rgba(255,255,255,0.04);
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: 12px;
  transition: all 0.25s var(--ease);
  position: relative; overflow: hidden;
}
.disease-card::before {
  content: '';
  position: absolute; top: 0; left: 0; right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--red-heart), var(--navy));
  opacity: 0;
  transition: opacity 0.25s;
}
.disease-card:hover { background: rgba(255,255,255,0.07); transform: translateY(-4px); }
.disease-card:hover::before { opacity: 1; }
.disease-icon { font-size: 28px; margin-bottom: 12px; }
.disease-card h4 {
  font-family: var(--font-display);
  font-size: 15px; font-weight: 700;
  color: var(--white); margin-bottom: 8px; line-height: 1.3;
}
.disease-card p {
  font-size: 12px; line-height: 1.6;
  color: rgba(255,255,255,0.55);
  margin-bottom: 14px;
}
.risk-tag {
  display: inline-block;
  font-size: 10px; font-weight: 700;
  letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--red-light);
  background: rgba(231,76,60,0.12);
  border: 1px solid rgba(231,76,60,0.25);
  padding: 3px 10px; border-radius: 20px;
}

.risk-factors {
  display: flex; flex-wrap: wrap; align-items: center; gap: 8px;
}
.risk-label {
  font-size: 11px; font-weight: 700;
  letter-spacing: 0.1em; text-transform: uppercase;
  color: rgba(255,255,255,0.4);
  margin-right: 4px;
}
.risk-pill {
  font-size: 12px; font-weight: 600;
  color: rgba(255,255,255,0.7);
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.1);
  padding: 5px 14px; border-radius: 20px;
  transition: all 0.2s;
}
.risk-pill:hover {
  background: rgba(255,255,255,0.12);
  color: var(--white);
}

/* ════════════════════════════════════════════════
   SLIDE 5 — PREVENTION LAYOUT
════════════════════════════════════════════════ */
.layout-prevention {
  display: flex; flex-direction: column;
  padding: 52px 80px;
}

.prevention-grid {
  display: grid; grid-template-columns: repeat(3, 1fr);
  gap: 16px; margin-bottom: 28px;
}
.prev-card {
  padding: 22px 20px;
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 12px;
  backdrop-filter: blur(10px);
  transition: all 0.25s var(--ease);
}
.prev-card:hover {
  background: rgba(255,255,255,0.1);
  transform: translateY(-3px);
  border-color: rgba(26,188,156,0.3);
}
.prev-icon { font-size: 28px; margin-bottom: 10px; }
.prev-card h4 {
  font-family: var(--font-display);
  font-size: 15px; font-weight: 700;
  color: var(--white); margin-bottom: 8px;
}
.prev-card p {
  font-size: 12px; line-height: 1.65;
  color: rgba(255,255,255,0.6);
}

.closing-quote {
  font-family: var(--font-display);
  font-size: 18px; font-style: italic;
  color: rgba(255,255,255,0.45);
  text-align: center;
  padding-top: 8px;
  border-top: 1px solid rgba(255,255,255,0.1);
}

/* ── Slide Entry Animations ───────────────────── */
.slide.active .section-label,
.slide.active .hero-badge,
.slide.active .hero-title,
.slide.active .slide-title,
.slide.active .hero-subtitle,
.slide.active .slide-desc,
.slide.active .hero-stats,
.slide.active .feature-list,
.slide.active .image-frame,
.slide.active .circuit-cards,
.slide.active .vessel-types,
.slide.active .disease-grid,
.slide.active .risk-factors,
.slide.active .prevention-grid,
.slide.active .closing-quote {
  animation: fadeUp 0.6s var(--ease) both;
}

.slide.active .hero-badge       { animation-delay: 0.05s; }
.slide.active .section-label    { animation-delay: 0.05s; }
.slide.active .hero-title       { animation-delay: 0.12s; }
.slide.active .slide-title      { animation-delay: 0.12s; }
.slide.active .hero-subtitle    { animation-delay: 0.20s; }
.slide.active .slide-desc       { animation-delay: 0.20s; }
.slide.active .hero-stats       { animation-delay: 0.28s; }
.slide.active .feature-list     { animation-delay: 0.28s; }
.slide.active .image-frame      { animation-delay: 0.22s; }
.slide.active .circuit-cards    { animation-delay: 0.28s; }
.slide.active .vessel-types     { animation-delay: 0.38s; }
.slide.active .disease-grid     { animation-delay: 0.24s; }
.slide.active .risk-factors     { animation-delay: 0.36s; }
.slide.active .prevention-grid  { animation-delay: 0.24s; }
.slide.active .closing-quote    { animation-delay: 0.40s; }

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(24px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ── Responsive ───────────────────────────────── */
@media (max-width: 900px) {
  .slide-content { padding: 40px 32px; }
  .layout-split  { grid-template-columns: 1fr; gap: 32px; }
  .disease-grid  { grid-template-columns: repeat(2, 1fr); }
  .prevention-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-title    { font-size: 48px; }
  .hero-stats    { flex-wrap: wrap; gap: 20px; }
  .stat-divider  { display: none; }
  .stat-item     { padding: 0; }
}

@media (max-width: 600px) {
  .slide-content { padding: 32px 20px; }
  .circuit-cards { grid-template-columns: 1fr; }
  .disease-grid  { grid-template-columns: 1fr; }
  .prevention-grid { grid-template-columns: 1fr; }
  .nav-arrow     { display: none; }
  .layout-full   { padding: 32px 20px; }
  .layout-prevention { padding: 32px 20px; }
}