/* UAVION — design tokens & layout */

:root {
  --color-bg: #0b1220;
  --color-bg-elevated: #121a2b;
  --color-bg-alt: #0f172a;
  --color-surface: rgba(18, 26, 43, 0.85);
  --color-surface-solid: #162033;
  --color-border: rgba(148, 163, 184, 0.18);
  --color-border-strong: rgba(255, 79, 0, 0.35);
  --color-text: #f8fafc;
  --color-text-muted: #94a3b8;
  --color-text-soft: #cbd5e1;
  --color-primary: #ff4f00;
  --color-primary-hover: #ff6a26;
  --color-primary-soft: rgba(255, 79, 0, 0.12);
  --color-accent: #38bdf8;
  --color-on-primary: #ffffff;
  --color-ring: #ff4f00;
  --font-heading: "Exo 2", "Segoe UI", sans-serif;
  --font-body: "IBM Plex Sans", "Segoe UI", sans-serif;
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --space-8: 4.5rem;
  --space-9: 6rem;
  --radius-sm: 0.5rem;
  --radius-md: 0.875rem;
  --radius-lg: 1.25rem;
  --shadow-card: 0 18px 50px rgba(0, 0, 0, 0.28);
  --header-h: 4.25rem;
  --container: 72rem;
  --transition: 200ms ease;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 1rem);
}

body {
  margin: 0;
  min-width: 320px;
  font-family: var(--font-body);
  font-size: 1.0625rem;
  line-height: 1.65;
  color: var(--color-text-soft);
  background:
    radial-gradient(ellipse 80% 50% at 10% -10%, rgba(255, 79, 0, 0.16), transparent 55%),
    radial-gradient(ellipse 60% 40% at 90% 0%, rgba(56, 189, 248, 0.08), transparent 50%),
    var(--color-bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

a {
  color: var(--color-primary-hover);
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.18em;
  transition: color var(--transition), background-color var(--transition), border-color var(--transition), opacity var(--transition);
}

a:hover {
  color: #ff8a4c;
}

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--color-ring);
  outline-offset: 3px;
}

h1,
h2,
h3,
h4 {
  font-family: var(--font-heading);
  color: var(--color-text);
  line-height: 1.2;
  margin: 0 0 var(--space-4);
  font-weight: 600;
  letter-spacing: -0.02em;
}

h1 {
  font-size: clamp(2rem, 4.5vw, 3.35rem);
  font-weight: 700;
}

h2 {
  font-size: clamp(1.65rem, 3vw, 2.35rem);
}

h3 {
  font-size: 1.2rem;
  margin-bottom: var(--space-3);
}

p {
  margin: 0 0 var(--space-4);
}

p:last-child {
  margin-bottom: 0;
}

ul,
ol {
  margin: 0;
  padding: 0;
}

.skip-link {
  position: absolute;
  left: var(--space-4);
  top: -100px;
  z-index: 1000;
  padding: 0.75rem 1rem;
  background: var(--color-primary);
  color: var(--color-on-primary);
  border-radius: var(--radius-sm);
  text-decoration: none;
  font-weight: 600;
}

.skip-link:focus {
  top: var(--space-4);
}

.container {
  width: min(100% - 2rem, var(--container));
  margin-inline: auto;
}

.section {
  padding: var(--space-8) 0;
  position: relative;
}

.section-alt {
  background: linear-gradient(180deg, rgba(15, 23, 42, 0.55), rgba(11, 18, 32, 0.2));
  border-block: 1px solid var(--color-border);
}

.section-heading {
  max-width: 42rem;
  margin-bottom: var(--space-7);
}

.section-lead {
  color: var(--color-text-muted);
  font-size: 1.0625rem;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin: 0 0 var(--space-3);
  color: var(--color-primary);
  font-family: var(--font-heading);
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.eyebrow::before {
  content: "";
  width: 1.25rem;
  height: 2px;
  background: var(--color-primary);
}

/* Header */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  backdrop-filter: blur(14px);
  background: rgba(11, 18, 32, 0.82);
  border-bottom: 1px solid var(--color-border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
  gap: var(--space-4);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: var(--color-text);
}

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

.brand-mark {
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 0.55rem;
  box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.08);
}

.brand-text {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.2rem;
  letter-spacing: 0.08em;
}

.nav-toggle {
  display: none;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface-solid);
  cursor: pointer;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
}

.nav-toggle-bar {
  display: block;
  width: 1.15rem;
  height: 2px;
  background: var(--color-text);
  transition: transform var(--transition), opacity var(--transition);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  list-style: none;
}

.nav-list a {
  display: inline-flex;
  align-items: center;
  min-height: 2.75rem;
  padding: 0.45rem 0.85rem;
  color: var(--color-text-muted);
  text-decoration: none;
  border-radius: 999px;
  font-size: 0.95rem;
  font-weight: 500;
}

.nav-list a:hover,
.nav-list a.is-active {
  color: var(--color-text);
  background: rgba(255, 255, 255, 0.04);
}

.nav-cta {
  background: var(--color-primary) !important;
  color: var(--color-on-primary) !important;
  margin-left: 0.35rem;
}

.nav-cta:hover {
  background: var(--color-primary-hover) !important;
}

/* Hero */

.hero {
  padding-top: clamp(3.5rem, 8vw, 6rem);
  padding-bottom: clamp(4rem, 9vw, 7rem);
  overflow: clip;
}

.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(148, 163, 184, 0.08) 1px, transparent 1px),
    linear-gradient(90deg, rgba(148, 163, 184, 0.08) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse 70% 60% at 50% 30%, #000 20%, transparent 75%);
  pointer-events: none;
}

.hero-inner {
  position: relative;
  max-width: 52rem;
}

.hero-lead {
  font-size: clamp(1.05rem, 2vw, 1.2rem);
  color: var(--color-text-muted);
  max-width: 44rem;
  margin-bottom: var(--space-6);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  margin-bottom: var(--space-6);
}

.hero-points {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  list-style: none;
}

.hero-points li {
  padding: 0.55rem 0.9rem;
  border: 1px solid var(--color-border);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.02);
  color: var(--color-text-soft);
  font-size: 0.92rem;
}

.hero-points li::before {
  content: "";
  display: inline-block;
  width: 0.45rem;
  height: 0.45rem;
  margin-right: 0.55rem;
  border-radius: 50%;
  background: var(--color-primary);
  vertical-align: middle;
}

/* Buttons */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 3rem;
  padding: 0.75rem 1.35rem;
  border-radius: 999px;
  border: 1px solid transparent;
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.98rem;
  text-decoration: none;
  cursor: pointer;
  transition: background-color var(--transition), border-color var(--transition), color var(--transition), transform var(--transition);
}

.btn:active {
  transform: translateY(1px);
}

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

.btn-primary:hover {
  background: var(--color-primary-hover);
  color: var(--color-on-primary);
}

.btn-secondary {
  background: transparent;
  color: var(--color-text);
  border-color: var(--color-border);
}

.btn-secondary:hover {
  border-color: rgba(255, 255, 255, 0.35);
  color: var(--color-text);
  background: rgba(255, 255, 255, 0.03);
}

/* Cards & grids */

.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-5);
}

.card {
  padding: var(--space-5);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  backdrop-filter: blur(8px);
  transition: border-color var(--transition), transform var(--transition);
}

.card:hover {
  border-color: var(--color-border-strong);
  transform: translateY(-2px);
}

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

.card-icon {
  width: 2.75rem;
  height: 2.75rem;
  display: grid;
  place-items: center;
  margin-bottom: var(--space-4);
  border-radius: 0.75rem;
  background: var(--color-primary-soft);
  color: var(--color-primary);
  border: 1px solid rgba(255, 79, 0, 0.25);
}

.card-icon svg {
  width: 1.35rem;
  height: 1.35rem;
}

.feature-list {
  display: grid;
  gap: var(--space-4);
}

.feature {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: var(--space-5);
  align-items: start;
  padding: var(--space-5);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: rgba(18, 26, 43, 0.55);
}

.feature-index {
  font-family: var(--font-heading);
  font-weight: 700;
  color: var(--color-primary);
  font-size: 1.15rem;
  letter-spacing: 0.04em;
}

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

.chip-grid {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  list-style: none;
}

.chip-grid li {
  padding: 0.85rem 1.15rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: var(--color-surface-solid);
  color: var(--color-text);
  font-weight: 500;
}

.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-4);
  list-style: none;
  counter-reset: step;
}

.step {
  position: relative;
  padding: var(--space-5);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  background: rgba(18, 26, 43, 0.55);
  counter-increment: step;
}

.step::before {
  content: counter(step, decimal-leading-zero);
  display: block;
  margin-bottom: var(--space-3);
  color: var(--color-primary);
  font-family: var(--font-heading);
  font-weight: 700;
  letter-spacing: 0.06em;
}

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

.about-grid {
  display: grid;
  grid-template-columns: 1.3fr 1fr;
  gap: var(--space-6);
  align-items: start;
}

.about-grid .section-heading {
  margin-bottom: 0;
}

.about-panel {
  padding: var(--space-5);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border-strong);
  background:
    linear-gradient(160deg, rgba(255, 79, 0, 0.1), transparent 55%),
    var(--color-surface-solid);
}

.requisites {
  display: grid;
  gap: var(--space-4);
  margin: 0;
}

.requisites div {
  display: grid;
  gap: 0.2rem;
}

.requisites dt {
  color: var(--color-text-muted);
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.requisites dd {
  margin: 0;
  color: var(--color-text);
  font-weight: 500;
}

.requisites a {
  color: var(--color-primary-hover);
  text-decoration: none;
}

.requisites a:hover {
  text-decoration: underline;
}

.cta-section {
  padding-top: var(--space-6);
}

.cta-panel {
  display: grid;
  grid-template-columns: 1.4fr auto;
  gap: var(--space-6);
  align-items: center;
  padding: clamp(1.75rem, 4vw, 2.75rem);
  border-radius: calc(var(--radius-lg) + 0.25rem);
  border: 1px solid var(--color-border-strong);
  background:
    radial-gradient(circle at 100% 0%, rgba(255, 79, 0, 0.2), transparent 45%),
    linear-gradient(135deg, #152038, #0f172a 60%);
  box-shadow: var(--shadow-card);
}

.cta-panel p {
  color: var(--color-text-muted);
}

.cta-actions {
  display: grid;
  gap: var(--space-3);
  justify-items: start;
}

.cta-note {
  font-size: 0.9rem;
  color: var(--color-text-muted);
}

/* Footer */

.site-footer {
  padding: var(--space-7) 0 var(--space-5);
  border-top: 1px solid var(--color-border);
  background: #080e18;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.3fr;
  gap: var(--space-6);
  margin-bottom: var(--space-7);
}

.footer-brand p {
  margin-top: var(--space-4);
  color: var(--color-text-muted);
  max-width: 18rem;
}

.footer-title {
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text);
  margin-bottom: var(--space-4);
}

.footer-links,
.footer-meta {
  list-style: none;
  display: grid;
  gap: 0.65rem;
}

.footer-links a,
.footer-bottom a {
  color: var(--color-text-muted);
  text-decoration: none;
}

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

.footer-meta {
  color: var(--color-text-muted);
  font-size: 0.92rem;
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  gap: var(--space-4);
  flex-wrap: wrap;
  padding-top: var(--space-5);
  border-top: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-size: 0.92rem;
}

/* Legal page */

.legal-hero {
  padding: calc(var(--header-h) + 2.5rem) 0 2.5rem;
}

.legal-content {
  max-width: 48rem;
}

.legal-content h2 {
  margin-top: var(--space-7);
  font-size: 1.4rem;
}

.legal-content ul {
  margin: 0 0 var(--space-4) 1.2rem;
  color: var(--color-text-muted);
}

.legal-content li {
  margin-bottom: 0.45rem;
}

.legal-meta {
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

/* Reveal */

.reveal {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 500ms ease, transform 500ms ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .card:hover,
  .btn:active {
    transform: none;
  }
}

/* Responsive */

@media (max-width: 1024px) {
  .card-grid,
  .steps {
    grid-template-columns: repeat(2, 1fr);
  }

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

@media (max-width: 860px) {
  .nav-toggle {
    display: inline-flex;
  }

  .site-nav {
    position: fixed;
    inset: var(--header-h) 0 auto 0;
    background: rgba(8, 14, 24, 0.96);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-4);
    transform: translateY(-120%);
    opacity: 0;
    pointer-events: none;
    transition: transform var(--transition), opacity var(--transition);
  }

  .site-nav.is-open {
    transform: none;
    opacity: 1;
    pointer-events: auto;
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
  }

  .nav-list a {
    width: 100%;
    border-radius: var(--radius-sm);
  }

  .nav-cta {
    margin-left: 0;
    justify-content: center;
  }

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

@media (max-width: 640px) {
  .section {
    padding: var(--space-7) 0;
  }

  .card-grid,
  .steps,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .feature {
    grid-template-columns: 1fr;
    gap: var(--space-3);
  }

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

  .btn {
    width: 100%;
  }
}