/* ─── Theme Toggle ───────────────────────────────────────────────────────── */
#theme-toggle {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  z-index: 99999; /* above texture overlay (99998) */
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.5rem;
}

#theme-toggle-btn {
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 50%;
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.1);
  transition:
    background 0.2s ease,
    border-color 0.2s ease,
    box-shadow 0.2s ease,
    transform 0.15s ease;
  flex-shrink: 0;
}

#theme-toggle-btn:hover {
  background: var(--color-accent-light);
  border-color: var(--color-border-hover);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
  transform: scale(1.06);
}

#theme-toggle-btn svg {
  display: block;
}

/* ─── Popover ────────────────────────────────────────────────────────────── */
#theme-popover {
  position: absolute;
  bottom: calc(100% + 0.625rem);
  right: 0;
  width: 192px;
  padding: 0.875rem 1rem;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 14px;
  box-shadow:
    0 8px 32px rgba(0, 0, 0, 0.12),
    0 2px 8px rgba(0, 0, 0, 0.06);
  display: flex;
  flex-direction: column;
  gap: 0.75rem;

  /* hidden state */
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateY(6px) scale(0.97);
  transform-origin: bottom right;
  transition:
    opacity 0.2s ease,
    visibility 0.2s ease,
    transform 0.2s cubic-bezier(0.34, 1.56, 0.64, 1);
}

#theme-popover.visible {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateY(0) scale(1);
}

/* ─── Labels row ─────────────────────────────────────────────────────────── */
#theme-popover-labels {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.75rem;
  color: var(--color-text-subtle);
}

#theme-pct-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--color-text-muted);
  min-width: 2.5rem;
  text-align: center;
  background: var(--color-accent-light);
  padding: 0.1rem 0.4rem;
  border-radius: 4px;
}

/* ─── Slider track ───────────────────────────────────────────────────────── */
#theme-track {
  position: relative;
  height: 6px;
  border-radius: 99px;
  background: var(--color-border);
  overflow: hidden;
  cursor: pointer;
}

#theme-track-fill {
  position: absolute;
  top: 0;
  left: 0;
  height: 100%;
  background: var(--color-text-muted);
  border-radius: 99px;
  pointer-events: none;
  transition: width 0.05s linear;
}

#theme-slider {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  cursor: pointer;
  margin: 0;
}

/* ─── Preset buttons ─────────────────────────────────────────────────────── */
#theme-presets {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.375rem;
}

.theme-preset {
  padding: 0.25rem 0;
  font-size: 0.65rem;
  font-family: var(--font-mono);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-muted);
  background: var(--color-accent-light);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  cursor: pointer;
  transition:
    background 0.15s ease,
    color 0.15s ease,
    border-color 0.15s ease,
    transform 0.1s ease;
  text-align: center;
}

.theme-preset:hover {
  background: var(--color-border);
  color: var(--color-text);
  border-color: var(--color-border-hover);
  transform: scale(1.04);
}

.theme-preset:active {
  transform: scale(0.97);
}

/* ─── Mobile ─────────────────────────────────────────────────────────────── */
@media (max-width: 480px) {
  #theme-toggle {
    bottom: 1rem;
    right: 1rem;
  }

  #theme-popover {
    width: 176px;
    right: 0;
  }
}