.shell {
  display: grid;
  grid-template-columns: var(--chem-sidebar-w) 1fr;
  grid-template-rows: var(--chem-topbar-h) 1fr;
  height: 100dvh;
  width: 100vw;
  overflow: hidden;
  background: var(--chem-bg);
}

.topbar {
  grid-column: 1 / -1;
  grid-row: 1;
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 0 16px;
  border-bottom: 1px solid var(--chem-border);
  background: var(--chem-bg);
  z-index: 20;
}

.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  width: calc(var(--chem-sidebar-w) - 32px);
  flex-shrink: 0;
  user-select: none;
  cursor: pointer;
}

.brand-mark {
  display: grid;
  place-items: center;
  color: var(--chem-text);
}

.brand-name {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.topbar-actions {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-left: auto;
  flex-shrink: 0;
}

.sidebar {
  grid-column: 1;
  grid-row: 2;
  position: relative;
  display: flex;
  flex-direction: column;
  min-width: 0;
  min-height: 0;
  overflow: hidden;
  border-right: 1px solid var(--chem-border);
  background: var(--chem-bg);
  transition: opacity 0.2s var(--chem-ease), border-color 0.2s var(--chem-ease);
}

.sidebar-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 16px 8px;
}

.sidebar-label {
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--chem-text-3);
}

.nav-list {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  padding: 2px 8px 12px;
  display: flex;
  flex-direction: column;
  gap: 1px;
}

.nav-group {
  display: flex;
  flex-direction: column;
  gap: 1px;
  padding-top: 8px;
}
.nav-group:first-child {
  padding-top: 2px;
}
.nav-group-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 26px;
  padding: 0 10px;
  border-radius: var(--chem-radius-sm);
  font-size: 10.5px;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--chem-text-3);
  cursor: pointer;
  transition: color var(--chem-speed) var(--chem-ease),
    background var(--chem-speed) var(--chem-ease);
}
.nav-group-head:hover {
  color: var(--chem-text);
  background: var(--chem-tint);
}
.nav-group-head.active {
  color: var(--chem-text);
}
.nav-group-count {
  font-family: var(--chem-mono);
  font-size: 9.5px;
  opacity: 0.65;
}
.nav-group-items {
  display: flex;
  flex-direction: column;
  gap: 1px;
}
.nav-group-injected {
  margin-top: 8px;
  padding-top: 8px;
  border-top: 1px solid var(--chem-border);
}

.arena {
  grid-column: 2;
  grid-row: 2;
  position: relative;
  min-width: 0;
  min-height: 0;
  overflow: auto;
  background: var(--chem-bg);
}

.shell {
  transition: grid-template-columns 0.24s var(--chem-ease);
}

@media (max-width: 1180px) {
  :root {
    --chem-sidebar-w: 204px;
  }
}

.boot {
  height: 100%;
  display: grid;
  place-items: center;
  color: var(--chem-text-3);
}

@media (max-width: 760px) {
  .shell {
    grid-template-columns: 1fr;
    grid-template-rows: var(--chem-topbar-h) auto 1fr;
  }
  .brand {
    width: auto;
  }
  .sidebar {
    grid-column: 1;
    grid-row: 2;
    border-right: none;
    border-bottom: 1px solid var(--chem-border);
  }
  .sidebar-head {
    display: none;
  }
  .nav-list {
    flex-direction: row;
    overflow-x: auto;
    overflow-y: hidden;
    padding: 6px 8px;
  }
  .arena {
    grid-column: 1;
    grid-row: 3;
  }

  .nav-group {
    flex-direction: row;
    align-items: center;
    gap: 4px;
    flex-shrink: 0;
    padding-top: 0;
  }
  .nav-group-head {
    height: 28px;
    white-space: nowrap;
  }
  .nav-group-count {
    display: none;
  }
  .nav-group-items {
    flex-direction: row;
    gap: 2px;
  }
}