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

body {
  font-family: system-ui, -apple-system, sans-serif;
  margin: 0;
  color: #1a202c;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* ── Header ─────────────────────────────── */
header { background: #2c5282; }

.header-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  max-width: 56rem;
  margin: 0 auto;
  padding: 1rem 1.5rem;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: #fff;
  font-weight: 700;
  font-size: 1.125rem;
}

.logo img { width: 2.5rem; }

.nav-toggle {
  display: none;
  background: none;
  border: 1px solid #fff;
  border-radius: 4px;
  padding: 0.4rem 0.5rem;
  cursor: pointer;
  color: #fff;
  line-height: 0;
}

nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 1.5rem;
}

nav a {
  color: #fff;
  text-decoration: none;
  font-size: 1.125rem;
}

@media (max-width: 767px) {
  .nav-toggle { display: block; }
  nav { width: 100%; }
  nav ul { flex-direction: column; gap: 0.75rem; padding: 0.75rem 0 0; display: none; }
  nav ul.open { display: flex; }
}

/* ── Main ────────────────────────────────── */
main {
  flex: 1;
  max-width: 56rem;
  margin: 0 auto;
  padding: 1rem;
  width: 100%;
}

@media (min-width: 768px) { main { padding: 4rem 2rem; } }

/* ── Footer ──────────────────────────────── */
footer { background: #f7fafc; }

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 56rem;
  margin: 0 auto;
  padding: 1rem 2rem;
  font-size: 0.875rem;
}

footer a { color: #1a202c; font-weight: 700; text-decoration: none; }

/* ── Typography ──────────────────────────── */
h1, h2, h3 { font-weight: 700; padding: 0.75rem; margin: 0; }
h1 { font-size: 1.5rem; }
h1.large { font-size: 2.25rem; }
h2 { font-size: 1.25rem; }
h3 { font-size: 1.125rem; }

.gray { color: #718096; }

p { padding: 0.75rem; font-size: 1.125rem; line-height: 1.6; margin: 0; }

ul, ol { padding-left: 2rem; }

/* ── Notice (yellow box) ─────────────────── */
.notice { margin: 0.5rem; padding: 1.5rem; font-size: 1.125rem; background: #fefcbf; line-height: 1.6; }

/* ── Arrow ───────────────────────────────── */
.arrow { font-size: 3.75rem; text-align: center; color: #cbd5e0; }

/* ── Collapse (details/summary) ──────────── */
.collapse { background: #2c5282; color: #fff; padding: 1rem; margin: 0.5rem 0; }

.collapse summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  font-weight: 700;
  font-size: 1.25rem;
  list-style: none;
  user-select: none;
}

.collapse summary::-webkit-details-marker { display: none; }

.collapse-arrow::after { content: '↓'; }
.collapse[open] .collapse-arrow::after { content: '↑'; }

.collapse-body { padding-top: 1rem; }
.collapse-body p { color: #fff; }
.collapse-body ul { color: #fff; font-size: 1.125rem; line-height: 1.8; }

/* ── Button ──────────────────────────────── */
.btn {
  display: inline-block;
  font-weight: 600;
  padding: 0.5rem 1rem;
  border: 2px solid #2c5282;
  border-radius: 4px;
  background: transparent;
  color: #2c5282;
  cursor: pointer;
  text-decoration: none;
  font-size: 1rem;
  transition: background 0.15s, color 0.15s;
}

.btn:hover { background: #2c5282; color: #fff; }

.btn-white { background: #fff; color: #2c5282; border-color: #fff; }
.btn-white:hover { background: #2c5282; color: #fff; }

/* ── Drone listing grid ──────────────────── */
.drone-grid { display: flex; flex-wrap: wrap; }

.drone-grid-item { width: 100%; }
@media (min-width: 640px) { .drone-grid-item { width: 50%; } }
@media (min-width: 768px) { .drone-grid-item { width: 33.333%; } }

.card {
  display: block;
  text-decoration: none;
  color: inherit;
  border-radius: 0.5rem;
  overflow: hidden;
  box-shadow: 0 4px 6px -1px rgba(0,0,0,.1), 0 2px 4px -1px rgba(0,0,0,.06);
  margin: 0.25rem;
}

.card img { width: 100%; display: block; }
.card-body { padding: 1rem 1.5rem 0.5rem; }
.card-title { font-weight: 700; font-size: 1.125rem; }
.card-tags { padding: 0.5rem 1.5rem 1rem; display: flex; flex-wrap: wrap; gap: 0.4rem; }

.tag {
  background: #edf2f7;
  border-radius: 9999px;
  padding: 0.2rem 0.7rem;
  font-size: 0.75rem;
  font-weight: 600;
  color: #4a5568;
}

/* ── Drone detail header ─────────────────── */
.drone-header { display: flex; flex-wrap: wrap; align-items: center; }
.drone-header-text { width: 100%; }
.drone-header-img { width: 100%; }

@media (min-width: 768px) {
  .drone-header-text { width: 50%; }
  .drone-header-img { width: 50%; }
}

.drone-header-img img { width: 100%; display: block; }

.text-center { text-align: center; }