/*===== Google Fonts =====*/
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=Fira+Code:wght@400;500&display=swap');

/*===== CSS Variables =====*/
:root {
  --dart-primary: #0175C2;
  --dart-secondary: #13B9FD;
  --dart-accent: #00C4B4;
  --dark-bg: #0a0e17;
  --dark-surface: #12182a;
  --dark-card: rgba(18, 24, 42, 0.85);
  --glass-bg: rgba(255, 255, 255, 0.05);
  --glass-border: rgba(255, 255, 255, 0.1);
  --text-primary: #ffffff;
  --text-secondary: rgba(255, 255, 255, 0.7);
  --text-muted: rgba(255, 255, 255, 0.5);
  --success: #4ade80;
  --warning: #fbbf24;
  --gradient-1: linear-gradient(135deg, #0175C2 0%, #00C4B4 100%);
  --gradient-2: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --shadow-glow: 0 0 60px rgba(1, 117, 194, 0.3);
}

/*===== Reset & Base =====*/
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html, body {
  height: 100%;
  overflow: hidden;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--dark-bg);
  color: var(--text-primary);
  line-height: 1.6;
}

/*===== Background Effects =====*/
.background-effects {
  position: fixed;
  inset: 0;
  pointer-events: none;
  overflow: hidden;
  z-index: 0;
}

.bg-gradient {
  position: absolute;
  inset: 0;
  background: 
    radial-gradient(ellipse 80% 50% at 50% -20%, rgba(1, 117, 194, 0.3) 0%, transparent 50%),
    radial-gradient(ellipse 60% 40% at 100% 100%, rgba(0, 196, 180, 0.2) 0%, transparent 50%),
    radial-gradient(ellipse 50% 30% at 0% 80%, rgba(102, 126, 234, 0.15) 0%, transparent 50%);
}

.bg-grid {
  position: absolute;
  inset: 0;
  background-image: 
    linear-gradient(rgba(255, 255, 255, 0.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
  background-size: 50px 50px;
}

.dart-decoration {
  position: absolute;
  width: 110px;
  opacity: 0.12;
  filter: drop-shadow(0 0 25px rgba(19, 185, 253, 0.65));
  animation: dartDrift 16s ease-in-out infinite;
}

.deco-1 {
  top: 7%;
  left: 6%;
}

.deco-2 {
  right: 8%;
  bottom: 13%;
  width: 150px;
  opacity: 0.1;
  animation-delay: -5s;
}

.deco-3 {
  top: 42%;
  right: 18%;
  width: 76px;
  opacity: 0.08;
  animation-delay: -10s;
}

@keyframes dartDrift {
  0%, 100% { transform: translateY(0) rotate(-8deg) scale(1); }
  50% { transform: translateY(-28px) rotate(10deg) scale(1.08); }
}

.floating-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(60px);
  animation: float 20s ease-in-out infinite;
}

.orb-1 {
  width: 400px;
  height: 400px;
  background: rgba(1, 117, 194, 0.3);
  top: -100px;
  right: -100px;
}

.orb-2 {
  width: 300px;
  height: 300px;
  background: rgba(0, 196, 180, 0.2);
  bottom: -50px;
  left: -50px;
  animation-delay: -7s;
}

.orb-3 {
  width: 200px;
  height: 200px;
  background: rgba(102, 126, 234, 0.25);
  top: 50%;
  left: 50%;
  animation-delay: -14s;
}

@keyframes float {
  0%, 100% { transform: translate(0, 0) scale(1); }
  25% { transform: translate(30px, -30px) scale(1.05); }
  50% { transform: translate(-20px, 20px) scale(0.95); }
  75% { transform: translate(20px, 30px) scale(1.02); }
}

/*===== Presentation Container =====*/
.presentation {
  position: relative;
  width: 100%;
  height: 100vh;
  z-index: 1;
}

/*===== Slide Styles =====*/
.slide {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 40px 80px;
  opacity: 0;
  visibility: hidden;
  transform: translateX(50px);
  transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.slide.active {
  opacity: 1;
  visibility: visible;
  transform: translateX(0);
}

.slide.prev {
  transform: translateX(-50px);
}

/*===== Slide Content =====*/
.slide-content {
  max-width: 1200px;
  width: 100%;
  text-align: center;
}

.slide-content.left-align {
  text-align: left;
}

/*===== Typography =====*/
h1 {
  font-size: clamp(2.5rem, 5vw, 4rem);
  font-weight: 800;
  margin-bottom: 1rem;
  background: var(--gradient-1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

h2 {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  margin-bottom: 1.5rem;
  color: var(--text-primary);
}

h3 {
  font-size: clamp(1.25rem, 2.5vw, 1.75rem);
  font-weight: 600;
  margin-bottom: 1rem;
  color: var(--dart-secondary);
}

p {
  font-size: clamp(1rem, 1.5vw, 1.25rem);
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

.subtitle {
  font-size: clamp(1.25rem, 2vw, 1.5rem);
  color: var(--text-secondary);
  margin-bottom: 2rem;
}

.highlight {
  color: var(--dart-accent);
  font-weight: 600;
}

.emoji {
  font-size: 1.2em;
}

/*===== Title Slide Specific =====*/
.title-slide .dart-logo {
  width: 150px;
  height: 150px;
  margin-bottom: 2rem;
  background: var(--gradient-1);
  border-radius: 30px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 4rem;
  box-shadow: var(--shadow-glow);
  animation: pulse 3s ease-in-out infinite;
}

.title-dart-logo {
  width: 150px;
  height: 150px;
  margin-bottom: 2rem;
  object-fit: contain;
  filter: drop-shadow(0 0 35px rgba(19, 185, 253, 0.7));
  animation: pulseLogo 3s ease-in-out infinite;
}

@keyframes pulseLogo {
  0%, 100% { transform: scale(1); filter: drop-shadow(0 0 35px rgba(19, 185, 253, 0.7)); }
  50% { transform: scale(1.06); filter: drop-shadow(0 0 55px rgba(0, 196, 180, 0.85)); }
}

@keyframes pulse {
  0%, 100% { transform: scale(1); box-shadow: var(--shadow-glow); }
  50% { transform: scale(1.05); box-shadow: 0 0 80px rgba(1, 117, 194, 0.5); }
}

.author-info {
  margin-top: 3rem;
  padding: 1rem 2rem;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 50px;
  backdrop-filter: blur(10px);
}

/*===== Glass Cards =====*/
.glass-card {
  background: var(--dark-card);
  border: 1px solid var(--glass-border);
  border-radius: 20px;
  padding: 2rem;
  backdrop-filter: blur(20px);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.glass-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 12px 48px rgba(0, 0, 0, 0.4);
}

/*===== Objectives List =====*/
.objectives-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  text-align: left;
  max-width: 700px;
  margin: 2rem auto;
}

.objective-item {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem 1.5rem;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 12px;
  font-size: 1.1rem;
  transition: all 0.3s ease;
  cursor: default;
}

.objective-item:hover {
  background: rgba(1, 117, 194, 0.1);
  border-color: var(--dart-primary);
  transform: translateX(10px);
}

.objective-item .check {
  color: var(--success);
  font-size: 1.5rem;
}

/*===== Code Block =====*/
.code-block {
  background: #1a1f35;
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  overflow: hidden;
  text-align: left;
  margin: 1.5rem 0;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.code-header {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1rem;
  background: rgba(0, 0, 0, 0.3);
  border-bottom: 1px solid var(--glass-border);
}

.code-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
}

.code-dot.red { background: #ff5f57; }
.code-dot.yellow { background: #febc2e; }
.code-dot.green { background: #28c840; }

.code-title {
  margin-left: auto;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.code-content {
  padding: 1.5rem;
  font-family: 'Fira Code', monospace;
  font-size: 0.95rem;
  line-height: 1.7;
  overflow-x: auto;
}

.code-content pre {
  margin: 0;
  white-space: pre-wrap;
}

/* Syntax Highlighting */
.keyword { color: #c792ea; }
.string { color: #c3e88d; }
.comment { color: #546e7a; font-style: italic; }
.function { color: #82aaff; }
.variable { color: #f78c6c; }
.type { color: #ffcb6b; }
.number { color: #f78c6c; }

/*===== Timeline =====*/
.timeline {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  text-align: left;
  max-width: 900px;
  margin: 0 auto;
}

.scrollable-timeline {
  max-height: min(56vh, 520px);
  overflow-y: auto;
  padding: 0 0.7rem 0.2rem 0;
  scrollbar-width: thin;
  scrollbar-color: var(--dart-secondary) rgba(255, 255, 255, 0.08);
}

.scrollable-timeline::after {
  content: "";
  position: sticky;
  bottom: -0.2rem;
  display: block;
  height: 28px;
  margin-top: -28px;
  pointer-events: none;
  background: linear-gradient(to bottom, transparent, rgba(10, 14, 23, 0.88));
}

.scrollable-timeline::-webkit-scrollbar {
  width: 9px;
}

.scrollable-timeline::-webkit-scrollbar-track {
  background: rgba(255, 255, 255, 0.08);
  border-radius: 99px;
}

.scrollable-timeline::-webkit-scrollbar-thumb {
  background: var(--gradient-1);
  border-radius: 99px;
}

.timeline-item {
  display: flex;
  gap: 1.5rem;
  padding: 1rem 1.5rem;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 12px;
  transition: all 0.3s ease;
}

.timeline-item:hover {
  background: rgba(1, 117, 194, 0.1);
  border-color: var(--dart-primary);
}

.timeline-year {
  font-weight: 700;
  color: var(--dart-secondary);
  min-width: 100px;
  font-size: 1.1rem;
}

.timeline-content h4 {
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.timeline-content p {
  font-size: 0.95rem;
  margin: 0;
}

/*===== Founder Cards =====*/
.founder-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.5rem;
  margin: 2rem auto 1.25rem;
  max-width: 980px;
}

.founder-card {
  display: grid;
  grid-template-columns: 150px 1fr;
  gap: 1.25rem;
  align-items: center;
  padding: 1.25rem;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 18px;
  text-align: left;
  transition: all 0.3s ease;
}

.founder-card:hover {
  background: rgba(1, 117, 194, 0.12);
  border-color: var(--dart-primary);
  transform: translateY(-5px);
}

.founder-photo {
  width: 150px;
  height: 150px;
  border-radius: 16px;
  object-fit: cover;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid var(--glass-border);
}

.founder-info h3 {
  margin-bottom: 0.5rem;
}

.founder-info p {
  margin: 0;
  font-size: 0.95rem;
}

.founder-note {
  max-width: 980px;
  margin: 0 auto;
  padding: 1rem 1.25rem;
  border: 1px solid rgba(0, 196, 180, 0.3);
  border-radius: 14px;
  background: rgba(0, 196, 180, 0.08);
  color: var(--text-secondary);
  text-align: left;
}

/*===== Feature Grid =====*/
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.feature-card {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  padding: 1.5rem;
  text-align: left;
  transition: all 0.3s ease;
}

.feature-card:hover {
  background: rgba(1, 117, 194, 0.1);
  border-color: var(--dart-primary);
  transform: translateY(-5px);
}

.feature-icon {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.feature-card h4 {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.feature-card p {
  font-size: 0.95rem;
  margin: 0;
}

/*===== Platform Showcase =====*/
.platform-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 2rem;
  margin: 2rem 0;
}

.platform-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  padding: 1.5rem 2rem;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  transition: all 0.3s ease;
}

.platform-item:hover {
  background: rgba(1, 117, 194, 0.15);
  transform: scale(1.05);
}

.platform-icon {
  font-size: 2.5rem;
}

.platform-name {
  font-weight: 500;
  color: var(--text-secondary);
}

/*===== App Gallery =====*/
.app-gallery {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.app-card {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  padding: 1.5rem;
  text-align: center;
  transition: all 0.3s ease;
}

.app-card:hover {
  background: rgba(1, 117, 194, 0.1);
  transform: translateY(-5px);
}

.app-card .app-icon {
  font-size: 2.5rem;
  margin-bottom: 0.75rem;
}

.app-card h4 {
  font-size: 1.1rem;
  margin-bottom: 0.25rem;
}

.app-card p {
  font-size: 0.85rem;
  margin: 0;
}

/*===== Ecosystem Diagram =====*/
.ecosystem-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.ecosystem-section {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  padding: 1.5rem;
  text-align: left;
}

.ecosystem-section h4 {
  color: var(--dart-secondary);
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.ecosystem-list {
  list-style: none;
}

.ecosystem-list li {
  padding: 0.4rem 0;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.ecosystem-list li::before {
  content: '├─';
  color: var(--text-muted);
  font-family: monospace;
}

.ecosystem-list li:last-child::before {
  content: '└─';
}

/*===== Comparison Table =====*/
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 2rem;
  background: var(--glass-bg);
  border-radius: 16px;
  overflow: hidden;
}

.comparison-table th,
.comparison-table td {
  padding: 1rem 1.5rem;
  text-align: left;
  border-bottom: 1px solid var(--glass-border);
}

.comparison-table th {
  background: rgba(1, 117, 194, 0.2);
  font-weight: 600;
  color: var(--dart-secondary);
}

.comparison-table tr:last-child td {
  border-bottom: none;
}

.comparison-table td:first-child {
  font-weight: 500;
}

/*===== Tips List =====*/
.tips-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
  text-align: left;
}

.tip-card {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  padding: 1.5rem;
  transition: all 0.3s ease;
}

.tip-card:hover {
  background: rgba(1, 117, 194, 0.1);
  border-color: var(--dart-primary);
}

.tip-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  background: var(--gradient-1);
  border-radius: 50%;
  font-weight: 700;
  font-size: 0.9rem;
  margin-bottom: 0.75rem;
}

.tip-card h4 {
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.tip-card p {
  font-size: 0.95rem;
  margin: 0;
}

/*===== Resources Grid =====*/
.resources-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.resource-card {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  padding: 1.5rem;
  text-align: center;
  transition: all 0.3s ease;
}

.resource-card:hover {
  background: rgba(1, 117, 194, 0.15);
  transform: translateY(-5px);
}

.resource-card .icon {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.resource-card h4 {
  margin-bottom: 0.5rem;
}

.resource-card a {
  color: var(--dart-secondary);
  text-decoration: none;
  font-size: 0.9rem;
}

.resource-card a:hover {
  text-decoration: underline;
}

/*===== Thank You Slide =====*/
.thank-you-content {
  text-align: center;
}

.thank-you-icon {
  font-size: 5rem;
  margin-bottom: 2rem;
  animation: bounce 2s ease-in-out infinite;
}

@keyframes bounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-20px); }
}

.next-step {
  margin-top: 2rem;
  padding: 1.5rem 2rem;
  background: var(--gradient-1);
  border-radius: 16px;
  display: inline-block;
}

.next-step h4 {
  color: white;
  margin-bottom: 0.5rem;
}

.next-step p {
  color: rgba(255, 255, 255, 0.9);
  margin: 0;
}

/*===== Navigation =====*/
.nav-controls {
  position: fixed;
  bottom: 30px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 0.75rem 1.5rem;
  background: var(--dark-card);
  border: 1px solid var(--glass-border);
  border-radius: 50px;
  backdrop-filter: blur(20px);
  z-index: 100;
}

.nav-btn {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 50%;
  color: var(--text-primary);
  font-size: 1.25rem;
  cursor: pointer;
  transition: all 0.3s ease;
}

.nav-btn:hover:not(:disabled) {
  background: var(--dart-primary);
  border-color: var(--dart-primary);
  color: white;
}

.nav-btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
}

.slide-counter {
  font-weight: 600;
  color: var(--text-secondary);
  min-width: 80px;
  text-align: center;
}

/*===== Progress Bar =====*/
.progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  height: 4px;
  background: var(--gradient-1);
  z-index: 100;
  transition: width 0.3s ease;
}

/*===== Responsive =====*/
@media (max-width: 768px) {
  .slide {
    padding: 30px 20px;
  }

  .feature-grid,
  .ecosystem-container,
  .tips-grid,
  .resources-grid {
    grid-template-columns: 1fr;
  }

  .timeline-item {
    flex-direction: column;
    gap: 0.5rem;
  }

  .founder-grid {
    grid-template-columns: 1fr;
  }

  .founder-card {
    grid-template-columns: 120px 1fr;
  }

  .founder-photo {
    width: 120px;
    height: 120px;
  }

  .comparison-table {
    font-size: 0.85rem;
  }

  .comparison-table th,
  .comparison-table td {
    padding: 0.75rem;
  }

  .nav-controls {
    bottom: 20px;
    padding: 0.5rem 1rem;
  }

  .nav-btn {
    width: 38px;
    height: 38px;
  }
}

@media (max-width: 480px) {
  .platform-grid {
    flex-direction: column;
  }

  .app-gallery {
    grid-template-columns: 1fr 1fr;
  }

  .founder-card {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .founder-photo {
    margin: 0 auto;
  }

  .founder-note {
    text-align: center;
  }
}