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

:root {
  --color-bg: #ffffff;
  --color-bg-alt: #f8fafc;
  --color-surface: #ffffff;
  --color-surface-hover: #e2e8f0;
  --color-border: #e2e8f0;
  --color-text: #1e293b;
  --color-text-muted: #64748b;
  --color-primary: #0284c7;
  --color-primary-dark: #0369a1;
  --color-accent: #0ea5e9;
  --color-accent-glow: rgba(2, 132, 199, 0.1);
  --font: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --radius: 12px;
  --radius-sm: 8px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font);
  background:
    radial-gradient(circle, rgba(0, 0, 0, 0.03) 1px, transparent 1px),
    var(--color-bg);
  background-size: 24px 24px;
  color: var(--color-text);
  line-height: 1.7;
  overflow-x: hidden;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition);
}

a:hover {
  color: var(--color-accent);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ---- Navbar ---- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  padding: 16px 0;
  transition: background var(--transition), box-shadow var(--transition), padding var(--transition);
}

.navbar.scrolled {
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
  padding: 10px 0;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--color-text);
  letter-spacing: -0.02em;
}

.nav-logo span {
  color: var(--color-primary);
}

.nav-logo:hover {
  color: var(--color-text);
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 32px;
}

.nav-links a {
  color: var(--color-text-muted);
  font-size: 0.875rem;
  font-weight: 500;
  transition: color var(--transition);
}

.nav-links a:hover {
  color: var(--color-text);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: var(--transition);
}

/* ---- Hero ---- */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 120px 24px 80px;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 50% at 50% 0%, rgba(2, 132, 199, 0.07) 0%, transparent 60%),
    radial-gradient(ellipse 50% 40% at 90% 90%, rgba(14, 165, 233, 0.05) 0%, transparent 50%),
    radial-gradient(ellipse 40% 30% at 10% 70%, rgba(2, 132, 199, 0.04) 0%, transparent 50%);
}

.hero-bg::before {
  content: '';
  position: absolute;
  top: -200px;
  right: -200px;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  border: 1px solid rgba(2, 132, 199, 0.06);
  pointer-events: none;
}

.hero-bg::after {
  content: '';
  position: absolute;
  bottom: -100px;
  left: -150px;
  width: 400px;
  height: 400px;
  border-radius: 50%;
  border: 1px solid rgba(2, 132, 199, 0.05);
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 800px;
}

.hero-tag {
  display: inline-block;
  background: rgba(2, 132, 199, 0.08);
  border: 1px solid rgba(2, 132, 199, 0.2);
  color: var(--color-primary);
  padding: 6px 16px;
  border-radius: 100px;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-bottom: 24px;
}

.hero h1 {
  font-size: clamp(3.5rem, 10vw, 7rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1;
  margin-bottom: 20px;
  background: linear-gradient(135deg, var(--color-text) 0%, var(--color-primary) 50%, var(--color-accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: clamp(1.1rem, 2.5vw, 1.35rem);
  color: var(--color-text-muted);
  max-width: 560px;
  margin: 0 auto 40px;
  line-height: 1.6;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  margin-bottom: 64px;
}

.btn {
  display: inline-flex;
  align-items: center;
  padding: 14px 28px;
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-weight: 600;
  transition: all var(--transition);
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: var(--color-primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--color-primary-dark);
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(2, 132, 199, 0.25);
}

.btn-outline {
  background: transparent;
  border: 1px solid var(--color-border);
  color: var(--color-text);
}

.btn-outline:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  transform: translateY(-2px);
}

.hero-stats {
  display: flex;
  gap: 48px;
  justify-content: center;
}

.stat {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.stat-value {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--color-primary);
  line-height: 1;
}

.stat-label {
  font-size: 0.8rem;
  color: var(--color-text-muted);
  margin-top: 6px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 500;
}

.scroll-indicator {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: var(--color-text-muted);
  font-size: 0.75rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  animation: pulse 2s ease-in-out infinite;
}

.scroll-arrow {
  width: 1px;
  height: 32px;
  background: linear-gradient(to bottom, var(--color-text-muted), transparent);
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

/* ---- Sections ---- */
.section {
  padding: 120px 0;
  position: relative;
}

.section:nth-child(even) {
  background: var(--color-bg-alt);
}

.section.about {
  background:
    radial-gradient(ellipse 40% 50% at 100% 0%, rgba(2, 132, 199, 0.04) 0%, transparent 70%),
    var(--color-bg-alt);
}

.section.vision {
  background:
    linear-gradient(135deg, rgba(2, 132, 199, 0.03) 0%, transparent 40%),
    linear-gradient(315deg, rgba(14, 165, 233, 0.03) 0%, transparent 40%),
    var(--color-bg);
}

.section.engineering {
  background:
    radial-gradient(ellipse 50% 30% at 0% 50%, rgba(2, 132, 199, 0.03) 0%, transparent 70%),
    var(--color-bg-alt);
}

.section.features {
  background:
    radial-gradient(ellipse 40% 40% at 100% 100%, rgba(14, 165, 233, 0.04) 0%, transparent 70%),
    var(--color-bg);
}

.section.roadmap {
  background:
    radial-gradient(ellipse 50% 40% at 0% 0%, rgba(2, 132, 199, 0.03) 0%, transparent 60%),
    var(--color-bg-alt);
}

.section.supported-by {
  background:
    radial-gradient(ellipse 60% 50% at 50% 100%, rgba(2, 132, 199, 0.03) 0%, transparent 60%),
    var(--color-bg);
}

.section.team {
  background:
    radial-gradient(ellipse 40% 40% at 80% 20%, rgba(14, 165, 233, 0.04) 0%, transparent 60%),
    var(--color-bg-alt);
}

.section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  border-radius: 3px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-accent));
  opacity: 0.5;
}

.hero::before {
  display: none;
}

.section-header {
  text-align: center;
  margin-bottom: 64px;
}

.section-tag {
  display: inline-block;
  color: var(--color-primary);
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 12px;
  background: rgba(2, 132, 199, 0.06);
  padding: 4px 14px;
  border-radius: 100px;
}

.section-header h2 {
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 700;
  letter-spacing: -0.02em;
}

/* ---- Vision ---- */
.vision-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  align-items: start;
}

.vision-card {
  text-align: center;
}

.vision-image-wrapper {
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--color-border);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
  transition: all var(--transition);
  aspect-ratio: 3 / 4;
}

.vision-image-wrapper:hover {
  border-color: var(--color-primary);
  box-shadow: 0 12px 32px rgba(2, 132, 199, 0.12);
  transform: translateY(-4px);
}

.vision-image {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.vision-caption {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  margin-top: 16px;
  line-height: 1.6;
}

/* ---- Subsections ---- */
.subsection {
  margin-bottom: 80px;
}

.subsection:last-child {
  margin-bottom: 0;
}

.subsection-title {
  font-size: clamp(1.4rem, 3vw, 1.75rem);
  font-weight: 600;
  margin-bottom: 40px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text);
}

/* ---- About ---- */
.about-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 64px;
  align-items: start;
}

.about-text .lead {
  font-size: 1.2rem;
  color: var(--color-text);
  margin-bottom: 20px;
  line-height: 1.7;
}

.about-text p {
  color: var(--color-text-muted);
  margin-bottom: 16px;
}

.about-text strong {
  color: var(--color-text);
}

.highlight-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 40px 32px;
  text-align: center;
  transition: all var(--transition);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.highlight-card:hover {
  border-color: var(--color-primary);
  box-shadow: 0 8px 30px rgba(2, 132, 199, 0.1);
  transform: translateY(-4px);
}

.card-icon {
  width: 56px;
  height: 56px;
  margin: 0 auto 20px;
  color: var(--color-primary);
}

.highlight-card h3 {
  font-size: 1.25rem;
  margin-bottom: 8px;
}

.highlight-card p {
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

/* ---- Architecture ---- */
.arch-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.arch-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 32px 28px;
  transition: all var(--transition);
  opacity: 0;
  transform: translateY(24px);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.arch-card.visible {
  opacity: 1;
  transform: translateY(0);
}

.arch-card:hover {
  border-color: var(--color-primary);
  box-shadow: 0 8px 24px rgba(2, 132, 199, 0.1);
  transform: translateY(-4px);
}

.arch-icon {
  width: 44px;
  height: 44px;
  color: var(--color-primary);
  margin-bottom: 20px;
}

.arch-card h3 {
  font-size: 1.1rem;
  margin-bottom: 8px;
  font-weight: 600;
}

.arch-card p {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  line-height: 1.6;
}

/* ---- Features ---- */
.features-list {
  max-width: 800px;
  margin: 0 auto;
}

.feature-item {
  display: flex;
  gap: 32px;
  padding: 40px 0;
  border-bottom: 1px solid var(--color-border);
  opacity: 0;
  transform: translateX(-24px);
  transition: all 0.5s ease;
}

.feature-item.visible {
  opacity: 1;
  transform: translateX(0);
}

.feature-item:last-child {
  border-bottom: none;
}

.feature-number {
  font-size: 3rem;
  font-weight: 800;
  color: var(--color-surface-hover);
  line-height: 1;
  min-width: 80px;
  transition: color var(--transition);
}

.feature-item:hover .feature-number {
  color: var(--color-primary);
}

.feature-content h3 {
  font-size: 1.2rem;
  margin-bottom: 8px;
  font-weight: 600;
}

.feature-content p {
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

/* ---- Components ---- */
.components-tabs {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-bottom: 48px;
}

.tab-btn {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  padding: 12px 24px;
  border-radius: 100px;
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font);
}

.tab-btn:hover {
  color: var(--color-text);
  border-color: var(--color-text-muted);
}

.tab-btn.active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: #fff;
}

.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
  animation: fadeIn 0.4s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

.component-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.component-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 28px 24px;
  transition: all var(--transition);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.component-card:hover {
  border-color: var(--color-primary);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
}

.component-card h4 {
  font-size: 1rem;
  margin-bottom: 8px;
  font-weight: 600;
}

.component-card p {
  color: var(--color-text-muted);
  font-size: 0.875rem;
  line-height: 1.6;
}

/* ---- System Diagram ---- */
.diagram-wrapper {
  overflow-x: auto;
  padding: 8px;
}

.diagram-box {
  display: grid;
  grid-template-columns: 1fr 1.2fr 1fr;
  gap: 32px;
  min-width: 700px;
}

.diagram-col {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0;
}

.diagram-node {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 16px 20px;
  text-align: center;
  font-size: 0.9rem;
  font-weight: 600;
  width: 100%;
  max-width: 220px;
  transition: all var(--transition);
}

.diagram-node:hover {
  border-color: var(--color-primary);
  box-shadow: 0 4px 16px rgba(2, 132, 199, 0.1);
}

.diagram-node small {
  display: block;
  color: var(--color-text-muted);
  font-weight: 400;
  font-size: 0.8rem;
  margin-top: 2px;
}

.diagram-node.battery {
  background: linear-gradient(135deg, #fff, rgba(2, 132, 199, 0.06));
  border-color: var(--color-primary);
}

.diagram-node.motor {
  background: linear-gradient(135deg, #fff, rgba(14, 165, 233, 0.06));
  border-color: var(--color-accent);
}

.diagram-arrow {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 6px 0;
}

.diagram-arrow::before {
  content: '';
  width: 1px;
  height: 20px;
  background: var(--color-border);
}

.diagram-arrow::after {
  content: '';
  width: 8px;
  height: 8px;
  border-right: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  transform: rotate(45deg);
  margin-top: -5px;
}

.arrow-label {
  font-size: 0.7rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 4px;
}

.diagram-aux {
  margin-top: 24px;
  background: var(--color-surface);
  border: 1px dashed var(--color-border);
  border-radius: var(--radius-sm);
  padding: 20px;
  width: 100%;
  max-width: 220px;
}

.diagram-aux h4 {
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--color-text-muted);
}

.diagram-aux ul {
  list-style: none;
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

.diagram-aux li {
  padding: 3px 0;
}

.diagram-aux li::before {
  content: '•';
  color: var(--color-primary);
  margin-right: 8px;
}

.center-power {
  padding-top: 40px;
}

/* ---- Roadmap ---- */
.roadmap-intro {
  text-align: center;
  color: var(--color-text-muted);
  max-width: 600px;
  margin: -32px auto 56px;
  font-size: 1.05rem;
}

.roadmap-timeline {
  position: relative;
  max-width: 700px;
  margin: 0 auto;
  padding-left: 40px;
}

.roadmap-timeline::before {
  content: '';
  position: absolute;
  left: 12px;
  top: 0;
  bottom: 0;
  width: 1px;
  background: linear-gradient(to bottom, var(--color-primary), var(--color-border));
}

.timeline-item {
  position: relative;
  padding: 0 0 48px 32px;
  opacity: 0;
  transform: translateY(20px);
  transition: all 0.5s ease;
}

.timeline-item.visible {
  opacity: 1;
  transform: translateY(0);
}

.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-dot {
  position: absolute;
  left: -34px;
  top: 4px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--color-primary);
  box-shadow: 0 0 8px rgba(2, 132, 199, 0.3);
}

.timeline-content h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 6px;
}

.timeline-content p {
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

/* ---- Footer ---- */
.footer {
  background: var(--color-bg);
  border-top: 1px solid var(--color-border);
  padding: 64px 0 32px;
}

.footer-content {
  display: flex;
  justify-content: space-between;
  gap: 48px;
  margin-bottom: 48px;
}

.footer-logo {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--color-text);
  display: inline-block;
  margin-bottom: 12px;
}

.footer-logo span {
  color: var(--color-primary);
}

.footer-logo:hover {
  color: var(--color-text);
}

.footer-brand p {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  max-width: 300px;
}

.footer-links h4 {
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 16px;
  color: var(--color-text-muted);
}

.footer-links ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.footer-links a {
  color: var(--color-text-muted);
  font-size: 0.9rem;
}

.footer-links a:hover {
  color: var(--color-text);
}

.footer-bottom {
  border-top: 1px solid var(--color-border);
  padding-top: 24px;
  text-align: center;
}

.footer-bottom p {
  color: var(--color-text-muted);
  font-size: 0.8rem;
}

/* ---- Supported By ---- */
.supporters {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 48px;
  flex-wrap: wrap;
}

.supporter-logo {
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 32px 48px;
  transition: all var(--transition);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.supporter-logo:hover {
  border-color: var(--color-primary);
  box-shadow: 0 8px 24px rgba(2, 132, 199, 0.1);
  transform: translateY(-4px);
}

.supporter-logo img {
  height: 48px;
  width: auto;
  opacity: 0.75;
  transition: opacity var(--transition);
}

.supporter-logo:hover img {
  opacity: 1;
}

.supporter-logo img.logo-light {
  opacity: 1;
  border-radius: 6px;
}

.supporter-logo:has(.logo-native) {
  background: var(--color-text);
}

.supporter-logo img.logo-native {
  opacity: 0.9;
}

.supporter-logo:has(.logo-native):hover {
  background: var(--color-primary);
}

/* ---- Team ---- */
.team-content {
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}

.team-image-wrapper {
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--color-border);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
  transition: all var(--transition);
}

.team-image-wrapper:hover {
  border-color: var(--color-primary);
  box-shadow: 0 12px 40px rgba(2, 132, 199, 0.12);
  transform: translateY(-4px);
}

.team-image {
  width: 100%;
  height: auto;
  display: block;
}

.team-caption {
  color: var(--color-text-muted);
  font-size: 1.05rem;
  margin-top: 28px;
  line-height: 1.7;
}

/* ---- Responsive ---- */
@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    background: #fff;
    flex-direction: column;
    padding: 80px 32px 32px;
    gap: 24px;
    transition: right var(--transition);
    box-shadow: -8px 0 30px rgba(0, 0, 0, 0.1);
  }

  .nav-links.open {
    right: 0;
  }

  .nav-links a {
    font-size: 1rem;
  }

  .hero-stats {
    gap: 24px;
  }

  .stat-value {
    font-size: 2rem;
  }

  .hero-actions {
    flex-direction: column;
    align-items: center;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

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

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

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

  .feature-item {
    flex-direction: column;
    gap: 8px;
  }

  .feature-number {
    font-size: 2rem;
    min-width: auto;
  }

  .diagram-box {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .center-power {
    padding-top: 0;
  }

  .footer-content {
    flex-direction: column;
    gap: 32px;
  }

  .section {
    padding: 80px 0;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: 3rem;
  }

  .hero-stats {
    flex-direction: column;
    gap: 16px;
  }
}