/* BURGER — мобильное меню и бургер-иконка */

.burger {
  display: none;
  width: 44px; height: 44px;
  margin-left: auto;
  place-items: center;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--bg-card);
  transition: border-color var(--dur-fast), background var(--dur-fast);
}
.burger:hover { border-color: var(--border-bright); background: var(--bg-card-hover); }
.burger:focus-visible { outline: 2px solid var(--accent-tg); outline-offset: 2px; }

.burger span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--text-0);
  position: relative;
  transition: transform var(--dur-base);
}

.burger span::before,
.burger span::after {
  content: '';
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  background: var(--text-0);
  transition: transform var(--dur-base), top var(--dur-base);
}

.burger span::before { top: -6px; }
.burger span::after { top: 6px; }

.burger.is-open span { background: transparent; }
.burger.is-open span::before { top: 0; transform: rotate(45deg); }
.burger.is-open span::after { top: 0; transform: rotate(-45deg); }

/* Мобильное меню до 900px */
@media (max-width: 899.98px) {
  .nav {
    position: fixed;
    inset: 64px 0 auto 0;
    flex-direction: column;
    align-items: stretch;
    gap: 8px;
    padding: var(--sp-md);
    padding-left: max(var(--sp-md), env(safe-area-inset-left));
    padding-right: max(var(--sp-md), env(safe-area-inset-right));
    padding-bottom: max(var(--sp-md), env(safe-area-inset-bottom));
    background: rgba(11, 15, 26, 0.97);
    backdrop-filter: blur(24px) saturate(1.4);
    -webkit-backdrop-filter: blur(24px) saturate(1.4);
    border-bottom: 1px solid var(--border);
    box-shadow: 0 24px 48px rgba(0, 0, 0, 0.5);
    transform: translateY(-120%);
    opacity: 0;
    transition: transform var(--dur-base) var(--ease-out),
                opacity var(--dur-fast);
    max-height: calc(100vh - 64px);
    max-height: calc(100dvh - 64px);
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
  }

  .nav.is-open { transform: translateY(0); opacity: 1; }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    width: 100%;
  }

  .nav a {
    padding: 14px 16px;
    border-radius: 12px;
    font-size: 15px;
    min-height: 48px;
    display: flex;
    align-items: center;
  }
  .burger { display: grid; }
  .nav .btn { margin: 10px 0 0; width: 100%; justify-content: center; }
}