/* ===== UFlyStar — industrial drone site ===== */
:root {
  --bg: #0d1117;
  --bg-alt: #131a24;
  --surface: #1a2230;
  --border: #263143;
  --text: #e8edf4;
  --muted: #9aa7b8;
  --accent: #f5a623;      /* amber — heat / desert */
  --accent-strong: #e8890c;
  --accent-ink: #1a1204;
  --radius: 14px;
  --maxw: 1120px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

.container { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

h1, h2, h3 { line-height: 1.2; font-weight: 700; letter-spacing: -0.01em; }
h2 { font-size: clamp(1.7rem, 3.2vw, 2.4rem); margin-bottom: 14px; }
h3 { font-size: 1.25rem; }

.eyebrow {
  color: var(--accent);
  font-size: 0.82rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: 12px;
}

.section { padding: 88px 0; }
.section-alt { background: var(--bg-alt); }
.section-lead { color: var(--muted); max-width: 640px; margin-bottom: 40px; }

/* ===== Buttons ===== */
.btn {
  display: inline-block;
  padding: 13px 28px;
  border-radius: 999px;
  font-weight: 600;
  text-decoration: none;
  font-size: 0.95rem;
  border: 1.5px solid transparent;
  cursor: pointer;
  transition: transform 0.15s ease, background 0.2s ease, border-color 0.2s ease;
}
.btn:hover { transform: translateY(-2px); }
.btn-solid { background: var(--accent); color: var(--accent-ink); }
.btn-solid:hover { background: var(--accent-strong); }
.btn-ghost { border-color: var(--border); color: var(--text); }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); }
.btn-sm { padding: 8px 18px; font-size: 0.88rem; }

/* ===== Nav ===== */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(13, 17, 23, 0.88);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  height: 66px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--text);
  text-decoration: none;
  letter-spacing: -0.02em;
}
.brand-mark { width: 26px; height: 26px; color: var(--accent); }
.nav-links {
  display: flex;
  align-items: center;
  gap: 26px;
}
.nav-links a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.94rem;
  font-weight: 500;
  transition: color 0.15s;
}
.nav-links a:hover { color: var(--text); }
.nav-links a.btn { color: var(--accent-ink); }
.nav-right { display: flex; align-items: center; gap: 14px; }

.lang-switch {
  display: flex;
  border: 1px solid var(--border);
  border-radius: 999px;
  overflow: hidden;
}
.lang-switch button {
  background: none;
  border: none;
  color: var(--muted);
  padding: 6px 13px;
  font-size: 0.82rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
}
.lang-switch button:hover { color: var(--text); }
.lang-switch button.active { background: var(--accent); color: var(--accent-ink); }

.nav-toggle { display: none; background: none; border: none; cursor: pointer; padding: 6px; }
.nav-toggle span {
  display: block;
  width: 22px; height: 2px;
  background: var(--text);
  margin: 5px 0;
  border-radius: 2px;
}

/* ===== Hero ===== */
.hero {
  position: relative;
  padding: 110px 0 90px;
  overflow: hidden;
  background:
    radial-gradient(ellipse 900px 500px at 75% -10%, rgba(245, 166, 35, 0.14), transparent 60%),
    var(--bg);
}
.hero-bg {
  position: absolute;
  inset: 0;
  color: var(--accent);
  opacity: 0.35;
  pointer-events: none;
}
.hero-topo { width: 100%; height: 100%; }
.hero-drone { animation: floaty 5s ease-in-out infinite; }
@keyframes floaty {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-14px); }
}
.hero-inner { position: relative; max-width: 720px; }
.hero h1 {
  font-size: clamp(2.1rem, 4.6vw, 3.4rem);
  margin-bottom: 20px;
}
.lead { font-size: 1.12rem; color: var(--muted); margin-bottom: 32px; max-width: 600px; }
.hero-cta { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 40px; }
.hero-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  list-style: none;
}
.hero-badges li {
  font-size: 0.85rem;
  color: var(--text);
  background: var(--surface);
  border: 1px solid var(--border);
  padding: 7px 16px;
  border-radius: 999px;
}
.hero-badges li::before { content: "✓ "; color: var(--accent); font-weight: 700; }

/* ===== Value strip ===== */
.strip { border-block: 1px solid var(--border); background: var(--bg-alt); padding: 44px 0; }
.strip-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 34px;
}
.strip-item strong { display: block; margin-bottom: 6px; font-size: 1rem; }
.strip-item span { color: var(--muted); font-size: 0.88rem; }

/* ===== Product cards ===== */
.cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px 28px;
  display: flex;
  flex-direction: column;
  transition: border-color 0.2s, transform 0.2s;
}
.card:hover { border-color: var(--accent); transform: translateY(-4px); }
.card-icon {
  width: 56px; height: 56px;
  color: var(--accent);
  background: rgba(245, 166, 35, 0.1);
  border-radius: 12px;
  display: grid;
  place-items: center;
  margin-bottom: 20px;
}
.card-icon svg { width: 34px; height: 34px; }
.card h3 { margin-bottom: 6px; }
.card-tag {
  color: var(--accent);
  font-size: 0.82rem;
  font-weight: 600;
  margin-bottom: 14px;
}
.card > p:not(.card-tag) { color: var(--muted); font-size: 0.93rem; margin-bottom: 18px; }
.card-list { list-style: none; margin-top: auto; }
.card-list li {
  font-size: 0.88rem;
  color: var(--text);
  padding: 8px 0 8px 24px;
  position: relative;
  border-top: 1px solid var(--border);
}
.card-list li::before {
  content: "▸";
  position: absolute;
  left: 4px;
  color: var(--accent);
}

/* ===== Model catalog ===== */
.card-link {
  display: inline-block;
  margin-top: 16px;
  color: var(--accent);
  font-size: 0.88rem;
  font-weight: 600;
  text-decoration: none;
}
.card-link:hover { text-decoration: underline; }

.cat-group { margin-top: 48px; }
.cat-group-head { max-width: 720px; margin-bottom: 28px; }
.cat-group-head h3 {
  font-size: 1.35rem;
  margin-bottom: 8px;
  padding-left: 14px;
  border-left: 4px solid var(--accent);
}
.cat-group-head p { color: var(--muted); font-size: 0.93rem; }

.model-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}
.model-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: border-color 0.2s, transform 0.2s;
}
.model-card:hover { border-color: var(--accent); transform: translateY(-3px); }
.model-photo {
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: #dfe7ef;
}
.model-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform 0.35s ease;
}
.model-card:hover .model-photo img { transform: scale(1.04); }
.model-body { padding: 20px 22px 22px; display: flex; flex-direction: column; flex: 1; }
.model-tag {
  color: var(--accent);
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 4px;
}
.model-body h4 { font-size: 1.15rem; margin-bottom: 8px; }
.model-intro { color: var(--muted); font-size: 0.88rem; margin-bottom: 14px; flex: 1; }
.model-specs { border-top: 1px solid var(--border); padding-top: 12px; }
.model-specs summary {
  cursor: pointer;
  color: var(--accent);
  font-size: 0.85rem;
  font-weight: 600;
  list-style: none;
  user-select: none;
}
.model-specs summary::-webkit-details-marker { display: none; }
.model-specs summary::after { content: " +"; }
.model-specs[open] summary::after { content: " −"; }
.model-specs table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 10px;
  font-size: 0.82rem;
}
.model-specs th, .model-specs td {
  text-align: left;
  padding: 6px 8px 6px 0;
  border-top: 1px solid var(--border);
  vertical-align: top;
  font-weight: 400;
}
.model-specs th { color: var(--muted); white-space: nowrap; padding-right: 14px; width: 42%; }
.model-specs td { color: var(--text); }
.model-cta { margin-top: 16px; align-self: flex-start; }
.ind-cta { margin-top: 16px; display: inline-block; }

/* ===== Industries ===== */
.ind-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 36px;
}
.ind-item {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 26px 24px;
  transition: border-color 0.2s;
}
.ind-item:hover { border-color: var(--accent); }
.ind-media {
  aspect-ratio: 16 / 9;
  border-radius: 10px;
  overflow: hidden;
  margin: -8px -6px 16px;
  background: var(--bg);
}
.ind-media video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.ind-emoji { font-size: 1.7rem; display: block; margin-bottom: 12px; }
.ind-item strong { display: block; margin-bottom: 6px; font-size: 1.02rem; }
.ind-item p { color: var(--muted); font-size: 0.88rem; }

/* ===== Services ===== */
.svc-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-top: 36px;
}
.svc {
  background: linear-gradient(145deg, var(--surface), var(--bg-alt));
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 34px 30px;
  position: relative;
}
.svc-num {
  font-size: 2.6rem;
  font-weight: 800;
  color: transparent;
  -webkit-text-stroke: 1.5px var(--accent);
  display: block;
  margin-bottom: 12px;
  opacity: 0.85;
}
.svc h3 { margin-bottom: 10px; }
.svc p { color: var(--muted); font-size: 0.93rem; }

.flow {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-top: 46px;
  padding: 22px;
  border: 1px dashed var(--border);
  border-radius: var(--radius);
}
.flow span {
  background: var(--surface);
  border: 1px solid var(--border);
  padding: 8px 20px;
  border-radius: 999px;
  font-size: 0.9rem;
  font-weight: 600;
}
.flow i { color: var(--accent); font-style: normal; font-weight: 700; }

/* ===== About ===== */
.about-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 56px;
  align-items: center;
}
.about-grid p { color: var(--muted); margin-bottom: 16px; }
.about-stats {
  list-style: none;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}
.about-stats li {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px 20px;
}
.about-stats strong {
  display: block;
  font-size: 1.9rem;
  color: var(--accent);
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: 6px;
}
.about-stats span { color: var(--muted); font-size: 0.85rem; }

/* ===== Contact ===== */
.contact {
  background:
    radial-gradient(ellipse 700px 400px at 50% 110%, rgba(245, 166, 35, 0.12), transparent 65%),
    var(--bg);
}
.contact-inner { max-width: 640px; text-align: center; }
.contact-inner .section-lead { margin-inline: auto; }
.contact-form { display: flex; flex-direction: column; gap: 14px; text-align: left; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.contact-form input,
.contact-form textarea {
  width: 100%;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  color: var(--text);
  padding: 13px 16px;
  font-size: 0.95rem;
  font-family: inherit;
  resize: vertical;
  transition: border-color 0.15s;
}
.contact-form input:focus,
.contact-form textarea:focus { outline: none; border-color: var(--accent); }
.contact-form input::placeholder,
.contact-form textarea::placeholder { color: var(--muted); }
.contact-form .btn { align-self: center; margin-top: 6px; }
.form-ok { color: var(--accent); text-align: center; font-weight: 600; }
.form-err { color: #e5484d; text-align: center; font-weight: 600; }
.hp-field { position: absolute !important; left: -9999px !important; width: 1px; height: 1px; opacity: 0; }

/* ===== Footer ===== */
.footer {
  border-top: 1px solid var(--border);
  padding: 44px 0;
  background: var(--bg-alt);
}
.footer-inner { text-align: center; }
.footer .brand { justify-content: center; margin-bottom: 12px; }
.footer p { color: var(--muted); font-size: 0.88rem; }
.footer-markets { margin-top: 10px; }
.footer-markets span:last-child { color: var(--text); font-weight: 600; letter-spacing: 0.02em; }
.footer-copy { margin-top: 8px; font-size: 0.8rem !important; }

/* ===== Reveal animation ===== */
.reveal { opacity: 0; transform: translateY(18px); transition: opacity 0.55s ease, transform 0.55s ease; }
.reveal.visible { opacity: 1; transform: none; }

/* ===== Responsive ===== */
@media (max-width: 900px) {
  .cards, .ind-grid, .model-grid { grid-template-columns: 1fr 1fr; }
  .strip-grid { grid-template-columns: 1fr 1fr; gap: 24px; }
  .about-grid { grid-template-columns: 1fr; gap: 36px; }
  .svc-grid { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  .section { padding: 64px 0; }
  .cards, .ind-grid, .strip-grid, .form-row, .about-stats, .model-grid { grid-template-columns: 1fr; }
  .hero { padding: 72px 0 64px; }

  .nav-toggle { display: block; }
  .nav-links {
    display: none;
    position: absolute;
    top: 66px;
    left: 0; right: 0;
    background: var(--bg-alt);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: 20px 24px;
    align-items: flex-start;
  }
  .nav-links.open { display: flex; }
}