.kanban-board {
  --kanban-zoom: 1;
  --kanban-column-width: 20rem;
  --kanban-gap: 1rem;
  display: flex;
  align-items: flex-start;
  gap: calc(var(--kanban-gap) * var(--kanban-zoom));
  width: 100%;
  padding: 0.25rem;
  overflow-x: auto;
  box-sizing: border-box;
  overscroll-behavior-x: contain;

  // Unlike transform, zoom reserves the scaled space in the flex layout.
  // This also keeps wrapping and the scrollable area aligned with the cards.
  & > .kanban-column { zoom: var(--kanban-zoom); }

  &.kanban-wrap {
    flex-wrap: wrap;
    overflow-x: visible;
  }
}

.kanban-column {
  display: flex;
  flex: 0 0 var(--kanban-column-width);
  flex-direction: column;
  min-height: 15rem;
  padding: 0.75rem;
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: 0.875rem;
  background: var(--md-sys-color-surface-variant);
  box-sizing: border-box;
  transition: border-color 160ms ease, background-color 160ms ease;

  &.is-drag-over {
    border-color: var(--md-sys-color-primary);
    background: color-mix(in srgb, var(--md-sys-color-primary-container) 55%, var(--md-sys-color-surface-variant));
  }
}

.kanban-column-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  padding: 0.25rem 0.25rem 0.75rem;
  color: var(--md-sys-color-on-surface-variant);
}

.kanban-column-title {
  margin: 0;
  font-size: 1rem;
  font-weight: 600;
}

.kanban-column-count {
  display: inline-flex;
  min-width: 1.5rem;
  min-height: 1.5rem;
  align-items: center;
  justify-content: center;
  padding: 0 0.375rem;
  border-radius: 999px;
  background: var(--md-sys-color-surface);
  color: var(--md-sys-color-on-surface);
  font-size: 0.75rem;
}

.kanban-column-body {
  display: flex;
  flex: 1 1 auto;
  flex-direction: column;
  gap: 0.75rem;
  min-height: 8rem;
}

.kanban-card {
  --kanban-card-accent: var(--md-sys-color-primary);
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 0.625rem;
  padding: 1rem;
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: 0.75rem;
  background: var(--kanban-card-color, var(--md-sys-color-surface));
  color: var(--kanban-card-text, var(--md-sys-color-on-surface));
  box-shadow: var(--md-sys-elevation-level1, 0 1px 2px rgba(0, 0, 0, 0.14));
  cursor: grab;
  user-select: none;
  overflow: hidden;
  transition: transform 160ms ease, opacity 160ms ease, box-shadow 160ms ease;

  &:active,
  &.is-dragging {
    cursor: grabbing;
  }

  &.is-dragging {
    opacity: 0.45;
    box-shadow: var(--md-sys-elevation-level3, 0 8px 18px rgba(0, 0, 0, 0.2));
  }

  &:focus-visible {
    outline: 2px solid var(--md-sys-color-primary);
    outline-offset: 2px;
  }

  &.kanban-card-accent {
    &::after {
      position: absolute;
      right: 0;
      bottom: 0;
      left: 0;
      height: 0.25rem;
      background: var(--kanban-card-accent);
      content: '';
      pointer-events: none;
    }
  }

  &.kanban-card-accent-top::after {
    top: 0;
    bottom: auto;
    left: 0;
    width: 100%;
    height: 0.25rem;
  }

  &.kanban-card-accent-right::after {
    top: 0;
    right: 0;
    bottom: 0;
    left: auto;
    width: 0.25rem;
    height: 100%;
  }

  &.kanban-card-accent-left::after {
    top: 0;
    right: auto;
    bottom: 0;
    left: 0;
    width: 0.25rem;
    height: 100%;
  }

  &.is-disabled,
  &[aria-disabled='true'] {
    cursor: not-allowed;
    opacity: 0.55;
    filter: saturate(0.55);
  }
}

.kanban-drag-image {
  position: fixed !important;
  top: -10000px !important;
  left: -10000px !important;
  z-index: -1;
  pointer-events: none;
  transform: rotate(2deg) scale(1.015);
  transform-origin: center;
}

.kanban-drop-preview {
  min-height: 4rem;
  box-sizing: border-box;
  border: 2px dashed var(--md-sys-color-primary);
  border-radius: 0.75rem;
  background: color-mix(in srgb, var(--md-sys-color-primary-container) 45%, transparent);
  pointer-events: none;
}

.kanban-card-title {
  margin: 0;
  font-size: 1rem;
  font-weight: 600;
}

.kanban-card-description {
  margin: 0;
  color: var(--md-sys-color-on-surface-variant);
  font-size: 0.875rem;
}

.kanban-card-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  color: var(--md-sys-color-on-surface-variant);
  font-size: 0.75rem;
}

.kanban-card-label {
  display: inline-flex;
  align-items: center;
  align-self: flex-start;
  padding: 0.1875rem 0.5rem;
  border-radius: 999px;
  background: var(--md-sys-color-secondary-container);
  color: var(--md-sys-color-on-secondary-container);
  font-size: 0.75rem;
}

.kanban-empty {
  display: grid;
  min-height: 5rem;
  place-items: center;
  border: 1px dashed var(--md-sys-color-outline);
  border-radius: 0.625rem;
  color: var(--md-sys-color-on-surface-variant);
  font-size: 0.875rem;
}

@media (max-width: 600px) {
  .kanban-board {
    --kanban-column-width: min(20rem, calc(100vw - 3rem));
  }
}