.railHost {
  min-height: 0;
  height: 100%;
  width: 220px;
  flex-shrink: 0;
  position: relative;
}

.peekBtn,
.backdrop,
.rail {
  pointer-events: auto;
}

.peekBtn {
  position: absolute;
  top: 8px;
  left: 8px;
  z-index: 24;
  min-height: 44px;
  padding: 0 12px;
  border-radius: 8px;
  border: 1px solid var(--border-subtle);
  background: var(--surface-glass, var(--surface-card));
  color: var(--text);
  font: inherit;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
}

.backdrop {
  position: absolute;
  inset: 0;
  z-index: 22;
  border: 0;
  padding: 0;
  margin: 0;
  background: rgba(7, 16, 18, 0.55);
  cursor: pointer;
}

.rail {
  display: flex;
  flex-direction: column;
  min-height: 0;
  height: 100%;
  width: 220px;
  flex-shrink: 0;
  border-right: 1px solid var(--surface-glass-border, var(--border-subtle));
  background: color-mix(in srgb, var(--surface-card) 82%, transparent);
}

.railOverlay {
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  z-index: 23;
  box-shadow: var(--shadow-md, 0 12px 32px rgba(0, 0, 0, 0.28));
}

.head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  padding: 10px 6px 4px 10px;
  flex-shrink: 0;
}

.headLabel {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 11px;
  font-weight: 650;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}

.closeBtn,
.newBtn {
  font: inherit;
  cursor: pointer;
}

.closeBtn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  margin: -8px -4px -8px 0;
  padding: 0;
  border: 0;
  border-radius: 8px;
  background: transparent;
  color: var(--muted);
}

.newBtn {
  margin: 6px 10px 8px;
  min-height: 44px;
  border-radius: 8px;
  border: 1px solid var(--border-subtle);
  background: var(--surface-muted);
  color: var(--text);
  font-size: 13px;
  font-weight: 600;
  flex-shrink: 0;
}

.headLabel::before {
  content: "";
  flex: none;
  width: 6px;
  height: 6px;
  transform: rotate(45deg);
  border-radius: 1px;
  background: var(--studio-accent-warm);
  box-shadow: 0 0 8px rgba(226, 179, 106, 0.6);
}

.newBtn:hover,
.closeBtn:hover,
.peekBtn:hover {
  background: var(--surface-raised);
  color: var(--text);
}

.newBtn:hover {
  border-color: var(--color-accent-warm-border);
}

.list {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-height: 0;
  overflow-y: auto;
  padding: 0 6px 10px;
}

.empty {
  margin: 8px 6px;
  font-size: 12px;
  color: var(--muted);
  line-height: 1.4;
}

.itemRow {
  display: flex;
  align-items: stretch;
  gap: 2px;
  border-radius: 8px;
}

.itemRow:hover,
.itemRow:focus-within {
  background: var(--surface-muted);
}

.item {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 2px;
  flex: 1;
  min-width: 0;
  min-height: 44px;
  padding: 8px 8px;
  border: 0;
  border-radius: 8px;
  background: transparent;
  color: var(--text);
  font: inherit;
  text-align: left;
  cursor: pointer;
}

.item:hover {
  background: transparent;
}

.itemCurrent {
  background: var(--surface-muted);
  box-shadow: inset 3px 0 0 var(--studio-accent-warm);
}

.itemActions {
  flex-shrink: 0;
  align-self: center;
  display: flex;
  align-items: center;
  gap: 0;
  margin-right: 2px;
  opacity: 0;
}

.itemRow:hover .itemActions,
.itemRow:focus-within .itemActions {
  opacity: 1;
}

.renameBtn,
.deleteBtn {
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  padding: 0;
  border: 0;
  border-radius: 6px;
  background: transparent;
  color: var(--muted);
  font: inherit;
  font-size: 11px;
  font-weight: 650;
  cursor: pointer;
}

.renameBtn:hover,
.deleteBtn:hover,
.deleteBtnConfirm {
  color: var(--text);
  background: var(--surface-raised);
}

.deleteBtnConfirm {
  width: auto;
  padding: 0 8px;
}

.renameForm {
  flex: 1;
  min-width: 0;
  padding: 6px 6px;
}

.renameInput {
  width: 100%;
  box-sizing: border-box;
  min-height: 32px;
  padding: 4px 8px;
  border-radius: 6px;
  border: 1px solid var(--link, var(--border-subtle));
  background: var(--surface-input, var(--surface-card));
  color: var(--text);
  font: inherit;
  font-size: 13px;
  font-weight: 600;
  outline: none;
}

.itemTitle {
  font-size: 13px;
  font-weight: 600;
  line-height: 1.3;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  max-width: 100%;
}

.itemMeta {
  font-size: 11px;
  color: var(--muted);
  line-height: 1.35;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  max-width: 100%;
}

/* Overlay drawer — keep in sync with OVERLAY_MQ in AgentSessionRail.tsx */
@media (max-width: 1023px) {
  .railHostOverlay {
    width: 0;
    min-width: 0;
    height: 0;
    overflow: visible;
  }

  .peekBtn {
    position: fixed;
    top: calc(44px + 8px);
    left: 8px;
    z-index: 30;
  }

  .backdrop {
    position: fixed;
    inset: 0;
    z-index: 31;
  }

  .railOverlay {
    position: fixed;
    top: 44px;
    left: 0;
    bottom: 0;
    z-index: 32;
    width: min(280px, calc(100vw - 48px));
    background: var(--surface-card);
    transform: translateX(-110%);
    visibility: hidden;
    pointer-events: none;
    transition:
      transform var(--motion-sm, 180ms) var(--ease-out, ease),
      visibility var(--motion-sm, 180ms) var(--ease-out, ease);
  }

  .railOverlay.railOpen {
    transform: translateX(0);
    visibility: visible;
    pointer-events: auto;
  }

  .itemActions {
    opacity: 1;
  }
}

@media (max-width: 1023px) and (prefers-reduced-motion: reduce) {
  .railOverlay,
  .railOverlay.railOpen {
    transition: none;
  }
}