/* Echo-Line Website Styles */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap');

:root {
  --primary: #0d2a5a;
  --primary-600: #0b234d;
  --bg: #ffffff;
  --text: #172b4d;
  --muted: #5f738c;
  --border: #e6ebf2;
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(13, 42, 90, 0.95);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  color: #fff;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.header-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  text-decoration: none;
}

.brand-logo {
  width: 36px;
  height: 36px;
  object-fit: contain;
}

.brand-name {
  font-weight: 700;
  letter-spacing: 0.3px;
}

.nav {
  display: flex;
  gap: 18px;
}

.nav a {
  color: #fff;
  text-decoration: none;
  opacity: 0.95;
  font-weight: 500;
}

.nav a:hover {
  opacity: 1;
}

.nav a.active {
  box-shadow: inset 0 -2px 0 0 #fff;
}

.nav .cta {
  background: #fff;
  color: var(--primary);
  padding: 8px 14px;
  border-radius: 20px;
  font-weight: 600;
}

/* Hero */
.hero {
  background: linear-gradient(135deg, #1a428a 0%, #091c3d 100%);
  color: #fff;
  padding: 60px 0 40px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.25fr 1fr;
  gap: 28px;
  align-items: center;
}

.hero-text h1 {
  margin: 0 0 12px;
  font-size: 36px;
  line-height: 1.15;
}

.hero-text p {
  margin: 0 0 18px;
  color: #e8eef7;
}

.hero-actions {
  display: flex;
  gap: 12px;
}

.hero-media img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 12px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
  object-fit: contain;
}

.btn {
  display: inline-block;
  padding: 12px 24px;
  border-radius: 50px;
  text-decoration: none;
  font-weight: 600;
  transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
}

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

.btn.outline {
  border: 2px solid #fff;
  color: #fff;
}

.btn.outline:hover {
  background: rgba(255, 255, 255, 0.12);
}

/* Sections */
.section {
  padding: 60px 0;
}

.section.alt {
  background: #f7f9fc;
}

.section h2 {
  margin: 0 0 12px;
  font-size: 30px;
  font-weight: 800;
  letter-spacing: 0.2px;
  color: var(--primary);
  position: relative;
  display: inline-block;
}

.section h2::after {
  content: "";
  display: block;
  width: 56px;
  height: 4px;
  background: var(--primary);
  border-radius: 2px;
  margin-top: 8px;
}

.section.alt h2 {
  color: var(--primary-600);
}

.section.alt h2::after {
  background: var(--primary-600);
}

.section-lead {
  color: var(--muted);
  margin-bottom: 24px;
}

/* About */
.about-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.about-grid h3 {
  margin: 4px 0 6px;
  font-size: 18px;
  color: var(--primary);
}

.about-grid p {
  margin: 0;
}

/* Tabs (Deep Dive) */
.tabs {
  display: flex;
  gap: 8px;
  margin-bottom: 12px;
  flex-wrap: wrap;
}

.tab {
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: #fff;
  color: var(--primary);
  cursor: pointer;
  font-weight: 600;
}

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

.tab-panels {
  border: 1px solid var(--border);
  border-radius: 12px;
  background: #fff;
  padding: 16px;
}

.tab-panel {
  display: none;
}

.tab-panel.is-active {
  display: block;
}

/* Preview */
.preview-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  align-items: center;
}

.device {
  width: 100%;
  max-width: 360px;
  margin: 0 auto;
  background: #111;
  border-radius: 32px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
  padding: 12px 12px 18px;
}

.device-camera {
  width: 60px;
  height: 6px;
  background: #222;
  border-radius: 3px;
  margin: 8px auto;
}

.device-screen {
  background: #000;
  border-radius: 24px;
  overflow: hidden;
  height: 640px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.carousel {
  width: 100%;
  height: 100%;
}

.carousel-track {
  position: relative;
  width: 100%;
  height: 100%;
}

.carousel-slide {
  position: absolute;
  inset: 0;
  opacity: 0;
  transition: opacity 0.4s ease-in-out;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 8px;
}

.carousel-slide.is-active {
  opacity: 1;
}

.carousel-slide img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.carousel-nav {
  display: flex;
  gap: 8px;
  justify-content: center;
  padding: 10px 0 0;
}

.carousel-nav .dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #cbd5e1;
  border: none;
  cursor: pointer;
}

.carousel-nav .dot.is-active {
  background: var(--primary);
}

.preview-copy h3 {
  margin: 0 0 8px;
  color: var(--primary);
}

/* Cards */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.card {
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 24px;
  background: #fff;
  transition: all 0.3s ease;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.02);
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
  border-color: transparent;
}

.card img {
  width: 100%;
  height: 180px;
  object-fit: cover;
  border-radius: 8px;
  margin-bottom: 10px;
}

.card h3 {
  margin: 6px 0 8px;
  font-size: 20px;
  color: var(--primary);
}

.card p {
  margin: 0;
  color: var(--text);
}

/* Steps */
.steps {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.step {
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 12px;
  align-items: start;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px;
}

.step-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  font-weight: 700;
}

/* Info grid */
.info-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.bullets {
  margin: 8px 0 0;
  padding-left: 18px;
}

.bullets li {
  margin: 6px 0;
  color: var(--muted);
}

/* Legal */
.policy-warning {
  margin: 16px 0;
  padding: 16px;
  background-color: #fef2f2;
  border-left: 4px solid #ef4444;
  border-radius: 8px;
  color: #7f1d1d;
  font-size: 14px;
}

.policy-warning p {
  margin: 8px 0 0;
}

.policy-warning strong {
  color: #b91c1c;
}

.legal-subnav {
  display: flex;
  gap: 10px;
  margin: 10px 0 18px;
  flex-wrap: wrap;
}

.legal-subnav a {
  display: inline-block;
  padding: 8px 12px;
  border: 1px solid var(--border);
  border-radius: 16px;
  background: #fff;
  color: var(--primary);
  text-decoration: none;
  font-weight: 600;
}

.legal-subnav a:hover {
  background: #f0f4f9;
}

.legal-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.legal-card {
  border: 1px solid var(--border);
  border-radius: 12px;
  background: #fff;
  padding: 16px;
}

.legal-card h3 {
  margin: 0 0 8px;
  font-size: 20px;
  color: var(--primary);
}

.legal-card p {
  margin: 0 0 10px;
}

.legal-card .bullets {
  padding-left: 18px;
}

.legal-card .bullets li {
  margin: 8px 0;
}

/* Use Cases */
.use-cases {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}

.use-case {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
  background: #fff;
}

.use-case h3 {
  margin: 4px 0 6px;
  font-size: 20px;
  color: var(--primary);
}

.use-case p {
  margin: 0;
  color: var(--text);
}

/* Security */
.security-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}

.security-grid h3 {
  margin: 4px 0 6px;
  font-size: 18px;
  color: var(--primary);
}

.security-grid p {
  margin: 0;
  color: var(--text);
}

/* Architecture */
.architecture-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}

.architecture-grid h3 {
  margin: 4px 0 6px;
  font-size: 18px;
  color: var(--primary);
}

.architecture-grid p {
  margin: 0;
}

/* FAQ */
.faq {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.faq-item {
  border: 1px solid var(--border);
  border-radius: 12px;
  background: #fff;
  overflow: hidden;
}

.faq-question {
  width: 100%;
  text-align: left;
  background: transparent;
  border: none;
  padding: 14px 16px;
  font-weight: 600;
  color: var(--primary);
  cursor: pointer;
}

.faq-answer {
  overflow: hidden;
  max-height: 0;
  transition: max-height 0.3s ease;
  padding: 0 16px;
}

.faq-answer.open {
  padding: 0 16px 14px;
}

/* Testimonials */
.testimonials {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.testimonials blockquote {
  margin: 0;
  border-left: 4px solid var(--primary);
  padding: 10px 16px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 8px;
}

.testimonials cite {
  display: block;
  margin-top: 8px;
  color: var(--muted);
  font-style: normal;
}

/* Gallery */
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.gallery-grid figure {
  margin: 0;
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
  background: #fff;
}

.gallery-grid img {
  width: 100%;
  height: 220px;
  object-fit: cover;
  display: block;
}

.gallery-grid figcaption {
  padding: 10px 12px;
  font-size: 14px;
  color: var(--muted);
}

/* Back to top */
.to-top {
  position: fixed;
  right: 18px;
  bottom: 24px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  border: none;
  box-shadow: 0 8px 24px rgba(13, 42, 90, 0.35);
  display: grid;
  place-items: center;
  font-size: 18px;
  cursor: pointer;
  opacity: 0;
  transform: translateY(20px);
  pointer-events: none;
  transition: all 0.2s ease;
  z-index: 1000;
}

.to-top.show {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

/* Founder */
.founder {
  max-width: 900px;
}

.founder p {
  color: var(--text);
}

/* Contact */
.contact {
  max-width: 900px;
}

.contact-card {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 18px;
  border: 1px solid var(--border);
  background: #fff;
  border-radius: 12px;
  padding: 16px;
}

.contact-cta {
  display: flex;
  align-items: center;
  justify-content: flex-end;
}

.contact a {
  color: var(--primary);
  text-decoration: none;
  font-weight: 600;
}

/* Footer */
.site-footer {
  background: var(--primary);
  color: #fff;
  padding: 20px 0;
}

.footer-content {
  text-align: center;
  font-size: 14px;
  opacity: 0.9;
}

/* Responsive */
@media (max-width: 980px) {
  .hero-grid {
    grid-template-columns: 1fr;
  }

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

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

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

  .use-cases {
    grid-template-columns: 1fr 1fr;
  }

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

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

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

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

  .contact-card {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 640px) {
  .cards {
    grid-template-columns: 1fr;
  }

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

  .use-cases {
    grid-template-columns: 1fr;
  }

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

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

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

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

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