/* DroneSkill design system
   Concept: dark aviation console + clean educational interface.
   Fonts: Manrope/Inter for UI, IBM Plex Mono/JetBrains Mono for technical accents.
*/
:root {
  --color-ink: #eaf4ff;
  --color-muted: #9fb3c8;
  --color-soft: #c9d8e7;
  --color-deep: #06111f;
  --color-deeper: #030812;
  --color-panel: rgba(13, 29, 48, 0.82);
  --color-panel-solid: #0d1d30;
  --color-card: #10243a;
  --color-line: rgba(130, 170, 210, 0.22);
  --color-primary: #2de2c5;
  --color-primary-dark: #12a895;
  --color-secondary: #7aa8ff;
  --color-accent: #ffb454;
  --color-danger: #ff6b6b;
  --color-success: #45dd8a;
  --color-link: #7fdcff;
  --color-heading: #ffffff;
  --color-button-text: #04101c;
  --shadow-soft: 0 20px 60px rgba(0, 0, 0, 0.28);
  --shadow-card: 0 14px 40px rgba(1, 8, 18, 0.28);
  --radius-sm: 12px;
  --radius-md: 20px;
  --radius-lg: 30px;
  --radius-pill: 999px;
  --container: 1160px;
  --section: clamp(56px, 8vw, 108px);
  --gap: clamp(18px, 3vw, 32px);
  --font-heading: "Manrope", "Inter", "Segoe UI", Arial, sans-serif;
  --font-body: "Inter", "Manrope", "Segoe UI", Arial, sans-serif;
  --font-mono: "IBM Plex Mono", "JetBrains Mono", Consolas, monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--color-soft);
  background:
    radial-gradient(circle at top left, rgba(45, 226, 197, 0.16), transparent 30rem),
    radial-gradient(circle at 80% 8%, rgba(122, 168, 255, 0.14), transparent 32rem),
    linear-gradient(180deg, var(--color-deep), var(--color-deeper) 46%, #050b14);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.65;
  min-height: 100vh;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(255,255,255,0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.035) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: linear-gradient(180deg, rgba(0,0,0,.82), transparent 82%);
  z-index: -1;
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--color-link); text-decoration: none; transition: color .2s ease, border-color .2s ease; }
a:hover { color: var(--color-primary); }
strong { color: var(--color-ink); }

.skip-link {
  position: absolute;
  left: -999px;
  top: 12px;
  background: var(--color-primary);
  color: var(--color-button-text);
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  z-index: 10;
}
.skip-link:focus { left: 12px; }

.container { width: min(100% - 32px, var(--container)); margin-inline: auto; }
.section { padding-block: var(--section); }
.section-tight { padding-block: clamp(36px, 5vw, 72px); }
.kicker {
  display: inline-flex;
  gap: 8px;
  align-items: center;
  margin: 0 0 14px;
  color: var(--color-primary);
  font: 700 13px/1 var(--font-mono);
  letter-spacing: .08em;
  text-transform: uppercase;
}
.kicker::before {
  content: "";
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--color-primary);
  box-shadow: 0 0 22px var(--color-primary);
}

h1, h2, h3 {
  color: var(--color-heading);
  font-family: var(--font-heading);
  line-height: 1.08;
  margin: 0 0 18px;
  letter-spacing: -0.035em;
}
h1 { font-size: clamp(40px, 8vw, 84px); max-width: 930px; }
h2 { font-size: clamp(30px, 4.8vw, 54px); }
h3 { font-size: clamp(21px, 2.4vw, 28px); letter-spacing: -0.02em; }
p { margin: 0 0 18px; }
.lead { font-size: clamp(19px, 2vw, 23px); color: var(--color-ink); max-width: 760px; }
.muted { color: var(--color-muted); }
.text-wide { max-width: 870px; }

.header {
  position: sticky;
  top: 0;
  z-index: 5;
  border-bottom: 1px solid var(--color-line);
  background: rgba(3, 8, 18, 0.76);
  backdrop-filter: blur(18px);
}
.header__inner {
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.logo {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--color-heading);
  font-weight: 800;
  letter-spacing: -0.02em;
}
.logo img { width: 42px; height: 42px; }
.logo span { color: var(--color-primary); }
.nav { display: flex; align-items: center; gap: 6px; flex-wrap: wrap; justify-content: flex-end; }
.nav a {
  color: var(--color-soft);
  border: 1px solid transparent;
  padding: 9px 12px;
  border-radius: var(--radius-pill);
  font-size: 15px;
}
.nav a:hover, .nav a[aria-current="page"] {
  color: var(--color-heading);
  border-color: var(--color-line);
  background: rgba(255,255,255,0.06);
}

.hero {
  padding-block: clamp(54px, 9vw, 118px) clamp(44px, 7vw, 90px);
  overflow: hidden;
}
.hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1.04fr) minmax(310px, .86fr);
  gap: var(--gap);
  align-items: center;
}
.hero__copy { position: relative; z-index: 1; }
.hero__copy p { max-width: 760px; }
.hero__visual {
  position: relative;
  padding: clamp(16px, 3vw, 26px);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  background: linear-gradient(145deg, rgba(15,36,58,.88), rgba(4,12,24,.88));
  box-shadow: var(--shadow-soft);
  overflow: hidden;
}
.hero__visual::after {
  content: "ONLINE • SIM • FIELD";
  position: absolute;
  right: 18px;
  bottom: 16px;
  color: rgba(234,244,255,.55);
  font: 700 12px/1 var(--font-mono);
  letter-spacing: .16em;
}
.hero__visual img { border-radius: calc(var(--radius-lg) - 10px); }
.hero__badges { display: flex; flex-wrap: wrap; gap: 12px; margin-block: 28px 0; }
.badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 13px;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-pill);
  background: rgba(255,255,255,0.055);
  color: var(--color-ink);
  font-size: 14px;
}
.badge::before { content: "✦"; color: var(--color-accent); }

.actions { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 30px; }
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 48px;
  padding: 13px 20px;
  border-radius: var(--radius-pill);
  border: 1px solid transparent;
  font-weight: 800;
  line-height: 1.1;
  cursor: pointer;
}
.button--primary {
  color: var(--color-button-text);
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  box-shadow: 0 12px 34px rgba(45, 226, 197, 0.20);
}
.button--primary:hover { color: var(--color-button-text); transform: translateY(-1px); }
.button--ghost {
  color: var(--color-heading);
  border-color: var(--color-line);
  background: rgba(255,255,255,0.055);
}
.button--ghost:hover { color: var(--color-primary); border-color: rgba(45,226,197,.5); }

.grid { display: grid; gap: var(--gap); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.card {
  position: relative;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  background: linear-gradient(180deg, rgba(16,36,58,.88), rgba(8,20,34,.74));
  box-shadow: var(--shadow-card);
  padding: clamp(22px, 3vw, 30px);
  overflow: hidden;
}
.card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto;
  height: 3px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-secondary), transparent);
  opacity: .75;
}
.card h3 { margin-top: 4px; }
.card p:last-child, .card ul:last-child, .card ol:last-child { margin-bottom: 0; }
.card--accent::before { background: linear-gradient(90deg, var(--color-accent), var(--color-primary)); }
.card__number {
  display: inline-grid;
  place-items: center;
  width: 42px;
  height: 42px;
  margin-bottom: 18px;
  border-radius: 14px;
  color: var(--color-button-text);
  background: var(--color-primary);
  font: 900 15px/1 var(--font-mono);
}

.panel {
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  background: var(--color-panel);
  box-shadow: var(--shadow-soft);
  padding: clamp(24px, 4vw, 44px);
}
.panel--split {
  display: grid;
  grid-template-columns: minmax(0, .9fr) minmax(280px, .6fr);
  gap: var(--gap);
  align-items: center;
}
.panel--light {
  background: linear-gradient(135deg, rgba(45,226,197,.11), rgba(122,168,255,.08));
}

.list-clean { list-style: none; margin: 0; padding: 0; display: grid; gap: 12px; }
.list-clean li {
  position: relative;
  padding-left: 28px;
  color: var(--color-soft);
}
.list-clean li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .68em;
  width: 12px;
  height: 12px;
  border-radius: 4px;
  background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
}
.checklist li::before { border-radius: 50%; background: var(--color-success); box-shadow: 0 0 18px rgba(69,221,138,.3); }

.timeline { counter-reset: step; display: grid; gap: 16px; }
.timeline__item {
  counter-increment: step;
  display: grid;
  grid-template-columns: 64px minmax(0, 1fr);
  gap: 18px;
  align-items: start;
}
.timeline__item::before {
  content: counter(step, decimal-leading-zero);
  display: grid;
  place-items: center;
  width: 56px;
  height: 56px;
  border-radius: 18px;
  color: var(--color-heading);
  background: rgba(255,255,255,.075);
  border: 1px solid var(--color-line);
  font: 900 16px/1 var(--font-mono);
}
.timeline__item h3 { margin-bottom: 8px; }

.stats { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 14px; margin-top: 26px; }
.stat {
  padding: 18px;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-line);
  background: rgba(255,255,255,0.055);
}
.stat strong {
  display: block;
  font: 900 clamp(28px, 4vw, 40px)/1 var(--font-heading);
  color: var(--color-primary);
  margin-bottom: 6px;
}
.stat span { color: var(--color-muted); font-size: 14px; }

.table-wrap { overflow-x: auto; border-radius: var(--radius-md); border: 1px solid var(--color-line); }
table { width: 100%; border-collapse: collapse; min-width: 760px; background: rgba(6,17,31,.58); }
th, td { padding: 16px 18px; border-bottom: 1px solid var(--color-line); text-align: left; vertical-align: top; }
th { color: var(--color-heading); font-size: 14px; letter-spacing: .04em; text-transform: uppercase; background: rgba(255,255,255,.06); }
tr:last-child td { border-bottom: 0; }

.quote {
  margin: 0;
  padding: clamp(22px, 4vw, 34px);
  border-left: 4px solid var(--color-accent);
  border-radius: var(--radius-md);
  background: rgba(255,180,84,.08);
  color: var(--color-ink);
  font-size: clamp(19px, 2vw, 24px);
}

.form {
  display: grid;
  gap: 16px;
}
.form__row { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
label { display: grid; gap: 7px; color: var(--color-ink); font-weight: 700; }
input, select, textarea {
  width: 100%;
  color: var(--color-ink);
  background: rgba(3,8,18,.66);
  border: 1px solid var(--color-line);
  border-radius: 16px;
  padding: 14px 15px;
  font: inherit;
  outline: none;
}
textarea { min-height: 130px; resize: vertical; }
input:focus, select:focus, textarea:focus { border-color: var(--color-primary); box-shadow: 0 0 0 4px rgba(45,226,197,.12); }
.form small { color: var(--color-muted); }

.cta {
  position: relative;
  overflow: hidden;
  border: 1px solid rgba(45,226,197,.32);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(circle at 15% 0, rgba(45,226,197,.24), transparent 34%),
    linear-gradient(135deg, rgba(13,29,48,.95), rgba(7,17,31,.92));
  padding: clamp(28px, 5vw, 54px);
  box-shadow: var(--shadow-soft);
}
.cta::after {
  content: "";
  position: absolute;
  width: 220px;
  height: 220px;
  right: -70px;
  bottom: -90px;
  border: 1px solid rgba(122,168,255,.35);
  border-radius: 50%;
  box-shadow: 0 0 0 28px rgba(122,168,255,.03), 0 0 0 58px rgba(122,168,255,.025);
}
.cta > * { position: relative; z-index: 1; }

.footer {
  border-top: 1px solid var(--color-line);
  padding-block: 44px;
  background: rgba(3,8,18,.66);
}
.footer__grid {
  display: grid;
  grid-template-columns: minmax(240px, 1fr) repeat(3, minmax(140px, .45fr));
  gap: 28px;
}
.footer h2, .footer h3 { font-size: 18px; margin-bottom: 12px; letter-spacing: -0.01em; }
.footer p, .footer a { font-size: 15px; }
.footer ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.footer__bottom { margin-top: 32px; color: var(--color-muted); font-size: 14px; }

.breadcrumbs { font-size: 14px; color: var(--color-muted); margin-bottom: 18px; }
.breadcrumbs a { color: var(--color-muted); }
.breadcrumbs span { color: var(--color-primary); }

.page-hero { padding-block: clamp(42px, 8vw, 92px) clamp(28px, 5vw, 54px); }
.page-hero h1 { max-width: 1000px; }
.page-hero .lead { max-width: 840px; }

@media (max-width: 980px) {
  .hero__grid, .panel--split, .grid--3, .grid--4, .footer__grid { grid-template-columns: 1fr; }
  .grid--2 { grid-template-columns: 1fr; }
  .header__inner { align-items: flex-start; flex-direction: column; padding-block: 14px; }
  .nav { justify-content: flex-start; }
  .stats { grid-template-columns: 1fr; }
}

@media (max-width: 620px) {
  body { font-size: 16px; }
  .container { width: min(100% - 24px, var(--container)); }
  .nav { gap: 4px; }
  .nav a { padding: 8px 10px; font-size: 14px; }
  .hero { padding-top: 36px; }
  .actions, .hero__badges { flex-direction: column; align-items: stretch; }
  .button { width: 100%; }
  .timeline__item { grid-template-columns: 1fr; }
  .form__row { grid-template-columns: 1fr; }
  .card, .panel, .cta { border-radius: 22px; }
}

.stacked-cards { display: grid; gap: var(--gap); align-content: start; }