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

:root {
  --teal: #25afb4;
  --dark: #4c5166;
  --dark-bg: #363839;
  --body-text: #747474;
  --light-bg: #f6f3f3;
  --white: #ffffff;
  --green-circle: #65bc7b;
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Open Sans', sans-serif;
  color: var(--body-text);
  line-height: 1.7;
  font-size: 16px;
}

a { color: var(--teal); text-decoration: none; transition: color .2s; }
a:hover { color: var(--dark); }

img { max-width: 100%; height: auto; display: block; }

h1, h2, h3, h4 { font-family: 'Montserrat', sans-serif; color: var(--dark); line-height: 1.3; }

.container { max-width: 1170px; margin: 0 auto; padding: 0 20px; }

/* ===== Header ===== */
.site-header {
  background: var(--white);
  box-shadow: 0 1px 6px rgba(0,0,0,.12);
  position: sticky;
  top: 0;
  z-index: 100;
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 70px;
}
.logo img { height: 50px; width: auto; }

/* Nav */
.main-nav { display: flex; align-items: center; gap: 0; }
.main-nav a {
  display: inline-block;
  padding: 24px 18px;
  color: var(--dark);
  font-family: 'Montserrat', sans-serif;
  font-size: 14px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .5px;
  border-top: 3px solid transparent;
  transition: border-color .25s, color .25s;
}
.main-nav a:hover,
.main-nav a.active {
  border-top-color: var(--teal);
  color: var(--teal);
}
.main-nav a.btn-login {
  background: var(--teal);
  color: var(--white);
  border-radius: 4px;
  padding: 10px 24px;
  margin-left: 10px;
  border-top: none;
}
.main-nav a.btn-login:hover { background: #1f969b; }

/* Mobile menu toggle */
.menu-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 24px;
  cursor: pointer;
  color: var(--dark);
  padding: 8px;
}

/* ===== Hero / Slider ===== */
.hero {
  position: relative;
  min-height: 420px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: var(--white);
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,.45);
  z-index: 1;
}
.hero-bg {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  z-index: 0;
}
.hero-content { position: relative; z-index: 2; padding: 60px 20px; }
.hero-content h1 {
  font-size: clamp(48px, 10vw, 110px);
  color: var(--white);
  font-weight: 700;
  letter-spacing: 2px;
}
.hero-content .subtitle {
  font-size: clamp(16px, 2.5vw, 25px);
  font-weight: 300;
  letter-spacing: 1px;
  line-height: 1.8;
  margin-top: 10px;
}
.hero-content .patent-badge {
  color: var(--teal);
  font-weight: 600;
  letter-spacing: 5px;
  font-size: clamp(14px, 2vw, 20px);
  margin-top: 6px;
}
.hero-buttons { margin-top: 30px; display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.hero-buttons a {
  display: inline-block;
  padding: 14px 36px;
  border: 2px solid var(--white);
  color: var(--white);
  font-family: 'Montserrat', sans-serif;
  font-weight: 600;
  font-size: 15px;
  text-transform: uppercase;
  letter-spacing: 1px;
  border-radius: 4px;
  transition: background .25s, color .25s;
}
.hero-buttons a:hover {
  background: var(--teal);
  border-color: var(--teal);
  color: var(--white);
}

/* ===== Split Section (home) ===== */
.split-section {
  display: grid;
  grid-template-columns: 1fr 1fr;
}
.split-text {
  padding: 100px 7%;
}
.split-text h3 {
  font-size: 32px;
  margin-bottom: 8px;
}
.split-text .separator {
  width: 100px;
  height: 2px;
  background: var(--teal);
  margin-bottom: 30px;
}
.split-text p { margin-bottom: 16px; }
.split-image {
  background-size: cover;
  background-position: center;
  min-height: 400px;
}

/* Feature list */
.feature-list { list-style: none; margin: 20px 0; }
.feature-list li {
  padding: 6px 0 6px 36px;
  position: relative;
  line-height: 1.7;
}
.feature-list li::before {
  content: '\f0c3';
  font-family: 'Font Awesome 6 Free';
  font-weight: 900;
  position: absolute;
  left: 0;
  color: var(--teal);
  font-size: 16px;
}
.api-note {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid #eee;
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 12px 28px;
  background: var(--teal);
  color: var(--white);
  font-family: 'Montserrat', sans-serif;
  font-weight: 600;
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: .5px;
  border-radius: 4px;
  border: 2px solid var(--teal);
  transition: background .25s, color .25s;
  cursor: pointer;
}
.btn:hover { background: #1f969b; border-color: #1f969b; color: var(--white); }
.btn-outline {
  background: transparent;
  border: 2px solid var(--white);
  color: var(--white);
}
.btn-outline:hover { background: var(--teal); border-color: var(--teal); }

/* ===== Stats / Facts ===== */
.stats-section {
  background-size: cover;
  background-position: center;
  position: relative;
  padding: 140px 0;
}
.stats-section::before {
  content: '';
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,.55);
}
.stats-grid {
  position: relative;
  z-index: 1;
  display: flex;
  justify-content: center;
  gap: 60px;
  flex-wrap: wrap;
}
.stat-item { text-align: center; }
.stat-circle {
  width: 220px;
  height: 220px;
  position: relative;
  margin: 0 auto 20px;
}
.stat-circle svg {
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}
.stat-circle .circle-bg {
  fill: none;
  stroke: rgba(255,255,255,.2);
  stroke-width: 11;
}
.stat-circle .circle-fill {
  fill: none;
  stroke: var(--green-circle);
  stroke-width: 11;
  stroke-linecap: round;
  transition: stroke-dashoffset 2s ease-out;
}
.stat-value {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  font-family: 'Montserrat', sans-serif;
  color: var(--white);
}
.stat-num {
  font-size: 50px;
  font-weight: 700;
  line-height: 1.1;
}
.stat-unit {
  font-size: 22px;
  font-weight: 300;
  letter-spacing: 1px;
}
.stat-label {
  color: var(--white);
  font-family: 'Montserrat', sans-serif;
  letter-spacing: 1px;
  font-size: 14px;
}

/* ===== CTA Section ===== */
.cta-section {
  background-size: cover;
  background-position: center;
  position: relative;
  padding: 180px 0;
  text-align: center;
}
.cta-section::before {
  content: '';
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,.5);
}
.cta-section .container { position: relative; z-index: 1; max-width: 800px; }
.cta-section h2 {
  font-size: clamp(32px, 5vw, 60px);
  color: var(--white);
  margin-bottom: 24px;
}
.cta-section p {
  color: var(--white);
  font-size: 20px;
  line-height: 1.8;
  margin-bottom: 36px;
}

/* ===== Page Title Bar ===== */
.page-title-bar {
  background: var(--light-bg);
  padding: 30px 0;
  border-bottom: 1px solid #e0e0e0;
}
.page-title-bar h1 { font-size: 32px; }
.breadcrumb {
  font-size: 13px;
  margin-top: 4px;
  color: var(--body-text);
}
.breadcrumb a { color: var(--body-text); }
.breadcrumb a:hover { color: var(--teal); }

/* ===== Demo Page ===== */
.demo-section { padding: 60px 0; }
.demo-section h2 {
  font-size: 18px;
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 16px;
}
.demo-section h2 .icon {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: var(--dark);
  color: var(--white);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  flex-shrink: 0;
}
.demo-section p { margin-bottom: 12px; }
.demo-section ol { margin: 16px 0 16px 24px; }
.demo-section ol li { margin-bottom: 8px; }
.demo-section .btn { margin: 24px 0; }

/* ===== About Page ===== */
.about-section { padding: 60px 0; }
.about-section h3 { font-size: 24px; margin: 32px 0 12px; }
.about-section h3:first-child { margin-top: 0; }
.about-section p { margin-bottom: 14px; }
.about-section .airr-logo { max-width: 300px; margin: 20px 0; }

.updates-timeline { margin: 24px 0; }
.updates-timeline .update-entry {
  padding: 10px 0 10px 20px;
  border-left: 3px solid var(--teal);
  margin-bottom: 0;
}
.updates-timeline .update-entry strong {
  color: var(--dark);
  font-family: 'Montserrat', sans-serif;
  font-size: 14px;
}

/* ===== Contact Page ===== */
.contact-section { padding: 60px 0; }
.contact-grid { display: grid; grid-template-columns: 1fr 2fr; gap: 60px; }
.contact-info h3 { font-size: 22px; margin-bottom: 16px; }
.contact-info p { margin-bottom: 12px; }
.contact-info .email-link {
  font-size: 18px;
  font-weight: 600;
  color: var(--teal);
}

.contact-form h3 { font-size: 22px; margin-bottom: 20px; }
.form-group { margin-bottom: 18px; }
.form-group label {
  display: block;
  font-weight: 600;
  font-size: 14px;
  margin-bottom: 6px;
  color: var(--dark);
}
.form-group label .required { color: #e74c3c; }
.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 10px 14px;
  border: 1px solid #ddd;
  border-radius: 4px;
  font-size: 15px;
  font-family: inherit;
  transition: border-color .2s;
}
.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--teal);
}
.form-group textarea { min-height: 100px; resize: vertical; }
.form-group .checkbox-wrap {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  font-size: 14px;
}
.form-group .checkbox-wrap input { width: auto; margin-top: 4px; }

/* ===== Imprint / Privacy ===== */
.legal-section { padding: 60px 0; }
.legal-section h2 { font-size: 22px; margin: 28px 0 12px; color: var(--dark); }
.legal-section h3 { font-size: 18px; margin: 20px 0 8px; }
.legal-section p { margin-bottom: 12px; }
.legal-section ul { margin: 12px 0 12px 24px; }
.legal-section ul li { margin-bottom: 6px; }

/* ===== Footer ===== */
.site-footer {
  background: var(--dark-bg);
  color: rgba(255,255,255,.7);
  text-align: center;
  padding: 30px 0;
  font-size: 14px;
}
.footer-links { margin-bottom: 12px; }
.footer-links a {
  color: rgba(255,255,255,.8);
  margin: 0 10px;
}
.footer-links a:hover { color: var(--white); }
.footer-social { margin-top: 12px; }
.footer-social a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border: 1px solid rgba(255,255,255,.3);
  border-radius: 4px;
  color: rgba(255,255,255,.7);
  margin: 0 4px;
  transition: all .2s;
}
.footer-social a:hover { border-color: var(--teal); color: var(--teal); }

/* ===== Responsive ===== */
@media (max-width: 900px) {
  .split-section { grid-template-columns: 1fr; }
  .split-image { min-height: 300px; }
  .stats-grid { gap: 30px; }
  .stat-circle { width: 160px; height: 160px; }
  .stat-value { font-size: 30px; }
  .contact-grid { grid-template-columns: 1fr; gap: 40px; }
}

@media (max-width: 768px) {
  .main-nav { display: none; }
  .main-nav.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 70px;
    left: 0;
    right: 0;
    background: var(--white);
    box-shadow: 0 4px 12px rgba(0,0,0,.1);
    z-index: 99;
  }
  .main-nav.open a { padding: 14px 20px; border-top: none; border-left: 3px solid transparent; }
  .main-nav.open a:hover,
  .main-nav.open a.active { border-left-color: var(--teal); border-top-color: transparent; }
  .main-nav.open a.btn-login { margin: 10px 20px; text-align: center; }
  .menu-toggle { display: block; }
  .hero { min-height: 320px; }
  .split-text { padding: 60px 5%; }
  .cta-section { padding: 100px 0; }
}