.mobile-nav-btn {
  display: none;
  width: 44px;
  height: 44px;
  background: transparent;
  border: 1px solid var(--border-color);
  cursor: pointer;
  align-items: center;
  justify-content: center;
  position: relative;
  clip-path: polygon(8px 0, 100% 0, calc(100% - 8px) 100%, 0 100%);
}

.header #authSlot {
  display: inline-flex;
  align-items: center;
  justify-content: flex-end;
  min-width: 86px;
  flex: 0 0 auto;
}

.header #languageSelect {
  min-width: 92px;
}

.mobile-nav-btn::before,
.mobile-nav-btn::after {
  content: '';
  position: absolute;
  left: 12px;
  right: 12px;
  height: 2px;
  background: var(--text-secondary);
  transition: transform 160ms ease, opacity 160ms ease;
}

.mobile-nav-btn::before {
  top: 16px;
  box-shadow: 0 7px 0 var(--text-secondary);
}

.mobile-nav-btn::after {
  top: 30px;
}

@media (max-width: 768px) {
  .mobile-nav-btn {
    display: inline-flex;
  }

  .header .nav > #languageSelect,
  .header .nav > #authSlot,
  .header .nav > #themeToggle {
    display: none;
  }
}

.mobile-nav-overlay {
  display: none;
}

@media (max-width: 768px) {
  .mobile-nav-overlay {
    display: block;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.65);
    z-index: 13000;
    opacity: 0;
    visibility: hidden;
    transition: opacity 160ms ease;
  }

  .mobile-nav-overlay.open {
    opacity: 1;
    visibility: visible;
  }

  .mobile-nav-drawer {
    position: absolute;
    top: 0;
    right: 0;
    height: 100%;
    width: min(360px, 86vw);
    background: var(--bg-secondary);
    border-left: 1px solid var(--border-color);
    transform: translateX(100%);
    transition: transform 200ms ease;
    display: flex;
    flex-direction: column;
    padding-bottom: env(safe-area-inset-bottom, 0px);
  }

  .mobile-nav-overlay.open .mobile-nav-drawer {
    transform: translateX(0);
  }

  .mobile-nav-drawer-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
    padding: calc(env(safe-area-inset-top, 0px) + 0.75rem) 0.75rem 0.75rem 0.75rem;
    border-bottom: 1px solid var(--border-color);
    background: rgba(34, 211, 238, 0.06);
  }

  .mobile-nav-title {
    font-family: 'Orbitron', sans-serif;
    letter-spacing: 2px;
    font-size: 0.85rem;
    color: var(--text-primary);
  }

  .mobile-nav-close {
    width: 44px;
    height: 44px;
    border: 1px solid var(--border-color);
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    cursor: pointer;
    font-size: 1.4rem;
    display: flex;
    align-items: center;
    justify-content: center;
    clip-path: polygon(8px 0, 100% 0, calc(100% - 8px) 100%, 0 100%);
  }

  .mobile-nav-actions-slot {
    padding: 0.75rem;
    border-bottom: 1px solid var(--border-color);
  }

  .mobile-nav-actions {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
  }

  .mobile-nav-section {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
  }

  .mobile-nav-section-title {
    font-family: 'Orbitron', sans-serif;
    font-size: 0.7rem;
    letter-spacing: 2px;
    color: var(--text-secondary);
    text-transform: uppercase;
  }

  .mobile-nav-row {
    border: 1px solid var(--border-color);
    background: var(--bg-tertiary);
    padding: 0.75rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    clip-path: polygon(10px 0, 100% 0, calc(100% - 10px) 100%, 0 100%);
  }

  .mobile-nav-row-label {
    font-size: 0.7rem;
    color: var(--text-secondary);
    letter-spacing: 1px;
  }

  .mobile-nav-drawer #languageSelect {
    width: 100%;
    min-height: 44px;
    padding: 0 0.75rem;
    border: 1px solid var(--border-color);
    background: var(--bg-primary);
    color: var(--text-primary);
    letter-spacing: 1px;
    clip-path: polygon(8px 0, 100% 0, calc(100% - 8px) 100%, 0 100%);
  }

  .mobile-nav-drawer #authSlot {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
  }

  .mobile-nav-drawer #themeToggle {
    align-self: flex-start;
  }

  .mobile-nav-links-slot {
    flex: 1;
    min-height: 0;
    overflow: auto;
    -webkit-overflow-scrolling: touch;
    padding: 0.75rem;
  }

  .mobile-nav-drawer .nav-links {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    list-style: none;
  }

  .mobile-nav-drawer .nav-link {
    display: block;
    width: 100%;
    padding: 0.9rem 1rem;
    border: 1px solid var(--border-color);
    background: var(--bg-tertiary);
    text-decoration: none;
    clip-path: polygon(10px 0, 100% 0, calc(100% - 10px) 100%, 0 100%);
  }
}

@media (max-width: 360px) {
  .header .logo {
    font-size: 1.15rem !important;
    letter-spacing: 1px !important;
  }

  .header .logo::after {
    right: -13px !important;
  }
}