/* DSA – Progress rings + Staggered fade-in */

/* Centered container: match HLD/LLD and Company Tracking (max-width + 24px padding). */
.main.main--dsa {
  max-width: 1200px;
  margin-left: auto;
  margin-right: auto;
  padding: 24px;
  width: 100%;
  box-sizing: border-box;
}

/* DSA Tech-SaaS tokens */
.main {
  --dsa-surface-gray: #F1F5F9;
  --dsa-shadow-card: 0 4px 6px -1px rgb(0 0 0 / 0.1);
  --dsa-shadow-card-hover: 0 8px 16px -4px rgba(0, 0, 0, 0.12);
}

.hidden {
  display: none !important;
}

.dsa-skip-link {
  position: absolute;
  top: -100px;
  left: 0.5rem;
  padding: 0.5rem 1rem;
  background: var(--color-accent);
  color: #fff;
  font-weight: 600;
  text-decoration: none;
  border-radius: var(--radius-sm);
  z-index: 200;
  transition: top 0.2s;
}
.dsa-skip-link:focus {
  top: 0.5rem;
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.dsa-hero {
  margin-bottom: 0.5rem;
}

.dsa-hero__title {
  margin: 0 0 0.35rem;
  font-size: 1.15rem;
  font-weight: 700;
}
@media (min-width: 768px) {
  .dsa-hero__title {
    font-size: 1.25rem;
  }
}

.dsa-hero__subtitle {
  margin: 0;
  font-size: 0.9rem;
  color: var(--color-text-muted);
}

.dsa-hero__jump-link {
  display: inline-block;
  margin-top: 0.5rem;
  padding: 0.35rem 0.75rem;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--color-accent);
  background: transparent;
  border: 1px solid var(--color-accent);
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: background 0.2s, color 0.2s;
}
.dsa-hero__jump-link:hover {
  background: var(--color-accent);
  color: #fff;
  text-decoration: none;
}

.dsa-loading {
  padding: 1.5rem;
  text-align: center;
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

.dsa-error {
  padding: 1rem 1.25rem;
  background: #fef2f2;
  border: 1px solid #fecaca;
  border-radius: var(--radius);
  margin-bottom: 1rem;
}
.dsa-error__message {
  margin: 0 0 0.75rem;
  color: #991b1b;
  font-size: 0.95rem;
}
.dsa-error__retry {
  padding: 0.4rem 0.85rem;
  border: 1px solid #b91c1c;
  background: #fff;
  color: #b91c1c;
  border-radius: var(--radius-sm);
  font-weight: 600;
  cursor: pointer;
  font-size: 0.875rem;
}
.dsa-error__retry:hover {
  background: #fef2f2;
}
.dsa-error__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}
.dsa-error__offline {
  padding: 0.4rem 0.85rem;
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text-muted);
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  cursor: pointer;
}
.dsa-error__offline:hover {
  color: var(--color-text);
  border-color: var(--color-accent);
}

/* Single filter row: progress stats + toolbar on one line */
.dsa-filter-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 0;
  margin-bottom: 0.75rem;
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
}

/* Horizontal toolbar: one line, left group + right group */
.dsa-toolbar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex: 1 1 auto;
  min-width: 0;
  min-height: 38px;
}

.dsa-toolbar__left {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 20px;
  flex-grow: 1;
  min-width: 0;
}

.dsa-toolbar__left .dsa-toolbar__label {
  white-space: nowrap;
}
.dsa-toolbar__search,
.dsa-toolbar__sort,
.dsa-topic-dropdown__trigger,
.dsa-difficulty-filter__btn,
.dsa-view-toggle__btn {
  height: 38px;
  box-sizing: border-box;
}
.dsa-toolbar .dsa-difficulty-filter__btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.dsa-toolbar__search {
  width: 100%;
  min-width: 120px;
  max-width: 280px;
  flex-shrink: 0;
  padding: 0.4rem 0.75rem;
  border: 1px solid #E2E8F0;
  border-radius: var(--radius-sm);
  background: #F8FAFC;
  color: var(--color-text);
  font-size: 0.9rem;
}
.dsa-toolbar__search:focus {
  outline: none;
  border-color: var(--color-accent);
  background: var(--color-surface);
}
.dsa-toolbar__search:focus-visible {
  border-color: var(--color-accent);
}

.dsa-toolbar__label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-text-muted);
  white-space: nowrap;
  flex-shrink: 0;
}

.dsa-toolbar__right {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-left: auto;
  flex-shrink: 0;
}

.dsa-toolbar__group {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}
.dsa-toolbar__group .dsa-toolbar__label {
  margin: 0;
  white-space: nowrap;
}
.dsa-toolbar__right .dsa-toolbar__group .dsa-toolbar__label {
  margin-right: 8px;
}

.dsa-toolbar__sort {
  padding: 0.4rem 0.6rem;
  border: 1px solid #E2E8F0;
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 0.875rem;
  min-width: 0;
}

.dsa-filters__clear-search {
  padding: 0.35rem 0.6rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-text-muted);
  font-size: 0.8125rem;
  cursor: pointer;
}
.dsa-filters__clear-search:hover {
  color: var(--color-accent);
}

.dsa-difficulty-filter {
  display: flex;
  flex-wrap: nowrap;
  gap: 0.25rem;
  flex-shrink: 0;
}
.dsa-difficulty-filter__btn {
  padding: 0.35rem 0.65rem;
  border: 1px solid #E2E8F0;
  border-radius: 999px;
  background: transparent;
  color: var(--color-text-muted);
  font-size: 0.8125rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s, color 0.2s;
  white-space: nowrap;
  flex-shrink: 0;
}
.dsa-difficulty-filter__btn:hover {
  background: var(--color-bg);
  border-color: var(--color-accent);
  color: var(--color-text);
}
.dsa-difficulty-filter__btn--active {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
}

.dsa-filters__label {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--color-text-muted);
}

.dsa-topic-dropdown {
  position: relative;
}

.dsa-topic-dropdown__trigger {
  padding: 0.4rem 0.65rem;
  border: 1px solid #E2E8F0;
  border-radius: var(--radius-sm);
  background: #ffffff;
  color: var(--color-text);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s;
  min-width: 100px;
  max-width: 180px;
  text-align: left;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.dsa-topic-dropdown__trigger:hover {
  background: var(--color-bg);
  border-color: var(--color-accent);
}
.dsa-topic-dropdown__trigger::after {
  content: ' ▾';
  font-size: 0.75em;
  opacity: 0.8;
}

.dsa-topic-dropdown__panel {
  position: absolute;
  top: 100%;
  left: 0;
  margin-top: 0.25rem;
  min-width: 220px;
  max-width: 320px;
  max-height: 280px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  box-shadow: var(--dsa-shadow-card);
  z-index: 50;
}
.dsa-topic-dropdown__panel.hidden {
  display: none !important;
}

.dsa-topic-dropdown__search {
  flex-shrink: 0;
  padding: 0.5rem 0.75rem;
  border: none;
  border-bottom: 1px solid var(--color-border);
  border-radius: var(--radius-sm) var(--radius-sm) 0 0;
  background: #F8FAFC;
  font-size: 0.875rem;
}
.dsa-topic-dropdown__search:focus {
  outline: none;
  border-bottom-color: var(--color-accent);
}

.dsa-topic-dropdown__list {
  overflow-y: auto;
  padding: 0.5rem;
  max-height: 220px;
}

.dsa-topic-dropdown__option {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 0.5rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.875rem;
  color: var(--color-text);
}
.dsa-topic-dropdown__option:hover {
  background: var(--color-bg);
}
.dsa-topic-dropdown__option input {
  margin: 0;
  cursor: pointer;
}
.dsa-topic-dropdown__option span {
  flex: 1;
}
.dsa-topic-dropdown__option .dsa-topic-dropdown__count {
  font-size: 0.75rem;
  color: var(--color-text-muted);
}

.dsa-view-toggle {
  display: flex;
  gap: 0;
}

.dsa-view-toggle__btn {
  padding: 0.4rem 0.85rem;
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s;
}

.dsa-view-toggle__btn:first-child {
  border-radius: 999px 0 0 999px;
}

.dsa-view-toggle__btn:last-child {
  border-radius: 0 999px 999px 0;
  margin-left: -1px;
}

.dsa-view-toggle__btn:hover {
  background: var(--color-bg);
  border-color: var(--color-accent);
}

.dsa-view-toggle__btn--active {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
}

/* Status bar: compact progress inside filter row */
.dsa-stats-bar {
  display: flex;
  flex-wrap: nowrap;
  align-items: center;
  gap: 0.5rem 0.75rem;
  padding: 0.25rem 0;
  margin-bottom: 0;
  border-bottom: none;
  flex-shrink: 0;
}

.dsa-stats-bar .dsa-ring {
  display: flex;
  flex-direction: row;
  align-items: center;
  gap: 0.5rem;
}

.dsa-stats-bar .dsa-ring__circle-wrap {
  position: relative;
  width: 36px;
  height: 36px;
  flex-shrink: 0;
}

.dsa-stats-bar .dsa-ring__circle {
  transform: rotate(-90deg);
  width: 36px;
  height: 36px;
}

.dsa-stats-bar .dsa-ring__circle-bg {
  fill: none;
  stroke-width: 3;
}
.dsa-stats-bar .dsa-ring--easy .dsa-ring__circle-bg { stroke: rgba(34, 197, 94, 0.25); }
.dsa-stats-bar .dsa-ring--medium .dsa-ring__circle-bg { stroke: rgba(234, 179, 8, 0.25); }
.dsa-stats-bar .dsa-ring--hard .dsa-ring__circle-bg { stroke: rgba(239, 68, 68, 0.25); }
.dsa-stats-bar .dsa-ring--total .dsa-ring__circle-bg { stroke: rgba(0, 98, 255, 0.2); }

.dsa-stats-bar .dsa-ring__circle-fill {
  fill: none;
  stroke-width: 3;
  stroke-linecap: round;
  transition: stroke-dashoffset 0.6s ease-out;
}

.dsa-stats-bar .dsa-ring__value {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: 0.65rem;
  font-weight: 700;
  color: var(--color-text);
}

.dsa-stats-bar .dsa-ring__label {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--color-text-muted);
}

.dsa-stats-bar .dsa-ring__count {
  font-size: 0.65rem;
  color: var(--color-text-muted);
}

/* Progress rings (shared circle styles) */
.dsa-ring__circle-wrap {
  position: relative;
  width: 100px;
  height: 100px;
}

.dsa-ring__circle {
  transform: rotate(-90deg);
}

.dsa-ring__circle-bg {
  fill: none;
  stroke: #E2E8F0;
  stroke-width: 6;
}
.dsa-ring--easy .dsa-ring__circle-bg { stroke: rgba(34, 197, 94, 0.3); }
.dsa-ring--medium .dsa-ring__circle-bg { stroke: rgba(234, 179, 8, 0.3); }
.dsa-ring--hard .dsa-ring__circle-bg { stroke: rgba(239, 68, 68, 0.3); }
.dsa-ring--total .dsa-ring__circle-bg { stroke: rgba(0, 98, 255, 0.2); }

.dsa-ring__circle-fill {
  fill: none;
  stroke-width: 6;
  stroke-linecap: round;
  transition: stroke-dashoffset 0.6s ease-out;
}

.dsa-ring--easy .dsa-ring__circle-fill { stroke: #22c55e; }
.dsa-ring--medium .dsa-ring__circle-fill { stroke: #eab308; }
.dsa-ring--hard .dsa-ring__circle-fill { stroke: #ef4444; }
.dsa-ring--total .dsa-ring__circle-fill { stroke: var(--color-accent); }

.dsa-ring__value {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text);
}

.dsa-ring__label {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--color-text-muted);
}

.dsa-ring__count {
  font-size: 0.75rem;
  color: var(--color-text-muted);
}

.dsa-ring {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
}

/* Category sections: flat tabs, subtle border */
.dsa-category {
  margin-bottom: 1rem;
  background: var(--color-surface);
  border: 1px solid #E2E8F0;
  border-radius: 4px;
  overflow: hidden;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.04);
}
.dsa-category.hidden {
  display: none !important;
}

.dsa-category__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.6rem 1rem;
  cursor: pointer;
  user-select: none;
  transition: background 0.2s;
}

.dsa-category__header:hover {
  background: var(--color-bg);
}
.dsa-category__header:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.dsa-category__header h2 {
  margin: 0;
  font-size: 1.1rem;
  font-weight: 600;
  letter-spacing: 0.01em;
}

.dsa-category__toggle {
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-muted);
  transition: transform 0.25s ease;
}
.dsa-category__toggle svg {
  width: 16px;
  height: 16px;
}

.dsa-category.is-open .dsa-category__toggle {
  transform: rotate(180deg);
}

.dsa-category__body {
  display: none;
  padding: 0 1rem 1rem;
}

.dsa-category.is-open .dsa-category__body {
  display: block;
}

.dsa-cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1rem;
}

.dsa-pagination {
  grid-column: 1 / -1;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 0.5rem 1rem;
  margin-top: 1rem;
  padding: 0.75rem 0;
  border-top: 1px solid var(--color-border);
}

.dsa-pagination__btn {
  padding: 0.4rem 0.75rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s;
}
.dsa-pagination__btn:hover:not(:disabled) {
  background: var(--color-bg);
  border-color: var(--color-accent);
}
.dsa-pagination__btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.dsa-pagination__pages {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
}

.dsa-pagination__num {
  min-width: 2rem;
  padding: 0.4rem 0.5rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s;
}
.dsa-pagination__num:hover {
  background: var(--color-bg);
  border-color: var(--color-accent);
}
.dsa-pagination__num--current {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
  cursor: default;
}
.dsa-pagination__num--current:hover {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
}

.dsa-pagination__ellipsis {
  padding: 0 0.25rem;
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

.dsa-pagination__size {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  margin-left: 0.5rem;
  font-size: 0.85rem;
  color: var(--color-text-muted);
}
.dsa-pagination__size-label {
  white-space: nowrap;
}
.dsa-pagination__size-select {
  padding: 0.3rem 0.5rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 0.85rem;
  cursor: pointer;
}

.dsa-cards-empty {
  margin: 0;
  padding: 1rem;
  color: var(--color-text-muted);
  font-size: 0.9rem;
  grid-column: 1 / -1;
}

.dsa-no-results {
  margin: 0 0 1rem;
  padding: 1rem 1.25rem;
  background: var(--color-to-study-muted);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
  font-size: 0.95rem;
}
.dsa-no-results__clear {
  background: none;
  border: none;
  padding: 0;
  color: var(--color-accent);
  font-size: inherit;
  cursor: pointer;
  text-decoration: underline;
}
.dsa-no-results__clear:hover {
  color: var(--color-accent-hover);
}

.dsa-cards--list {
  grid-template-columns: 1fr;
  gap: 0.25rem;
}

.dsa-card--list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.4rem 0.75rem;
  padding: 0.35rem 0.75rem;
  min-height: 52px;
  box-sizing: border-box;
}
.dsa-cards--list .dsa-card--list:nth-child(even) {
  background: #F8FAFC;
}

.dsa-card--list .dsa-card__link,
.dsa-card--list .dsa-card__link--block {
  flex: 1 1 auto;
  min-width: 0;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-top: 0;
}

.dsa-card--list .dsa-card__title {
  margin: 0;
  flex: 1 1 auto;
  min-width: 0;
  font-size: 0.95rem;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.dsa-card--list .dsa-card__meta {
  margin: 0;
  flex-shrink: 0;
  font-size: 0.8rem;
}

.dsa-card--list .dsa-card__open,
.dsa-card--list .dsa-card__open--impl,
.dsa-card--list .dsa-card__view-code {
  margin-top: 0;
  flex-shrink: 0;
}

.dsa-card--list .dsa-card__badge {
  margin-top: 0;
  flex-shrink: 0;
}

.dsa-card--list .dsa-card__actions {
  margin-top: 0;
  padding-top: 0;
  border-top: none;
  flex-shrink: 0;
}

.dsa-card {
  padding: 0.75rem 1rem;
  background: var(--color-surface);
  border: 1px solid #E2E8F0;
  border-radius: 4px;
  box-shadow: var(--dsa-shadow-card);
  opacity: 0;
  transform: translateY(12px);
  animation: dsa-card-in 0.4s ease-out forwards;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.dsa-card:hover {
  border-color: var(--color-border);
  box-shadow: var(--dsa-shadow-card-hover);
}

.dsa-category.is-open .dsa-card:nth-child(1) { animation-delay: 0.05s; }
.dsa-category.is-open .dsa-card:nth-child(2) { animation-delay: 0.1s; }
.dsa-category.is-open .dsa-card:nth-child(3) { animation-delay: 0.15s; }
.dsa-category.is-open .dsa-card:nth-child(4) { animation-delay: 0.2s; }
.dsa-category.is-open .dsa-card:nth-child(5) { animation-delay: 0.25s; }
.dsa-category.is-open .dsa-card:nth-child(6) { animation-delay: 0.3s; }
.dsa-category.is-open .dsa-card:nth-child(7) { animation-delay: 0.35s; }
.dsa-category.is-open .dsa-card:nth-child(8) { animation-delay: 0.4s; }
.dsa-category.is-open .dsa-card:nth-child(n+9) { animation-delay: 0.45s; }

@keyframes dsa-card-in {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.dsa-card__title {
  margin: 0 0 0.1rem;
  font-size: 0.95rem;
  font-weight: 600;
  line-height: 1.3;
}

.dsa-card__meta {
  font-size: 0.8rem;
  font-weight: 400;
  color: var(--color-text-muted);
  margin-bottom: 0.2rem;
}

.dsa-card__open {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  margin-top: 0.4rem;
  padding: 0.35rem 0.65rem;
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--color-accent);
  background: transparent;
  border: 1px solid var(--color-accent);
  border-radius: var(--radius-sm);
  transition: background 0.2s, color 0.2s;
}
.dsa-card__open::before {
  content: '';
  width: 0.85em;
  height: 0.85em;
  background: currentColor;
  mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='currentColor' stroke-width='2'%3E%3Cpath d='M18 13v6a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2V8a2 2 0 0 1 2-2h6'/%3E%3Cpolyline points='15 3 21 3 21 9'/%3E%3Cline x1='10' y1='14' x2='21' y2='3'/%3E%3C/svg%3E") no-repeat center;
  mask-size: contain;
  -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='currentColor' stroke-width='2'%3E%3Cpath d='M18 13v6a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2V8a2 2 0 0 1 2-2h6'/%3E%3Cpolyline points='15 3 21 3 21 9'/%3E%3Cline x1='10' y1='14' x2='21' y2='3'/%3E%3C/svg%3E") no-repeat center;
  -webkit-mask-size: contain;
}

.dsa-card__link:hover .dsa-card__open {
  background: var(--color-accent);
  color: #fff;
}

.dsa-card__badge {
  display: inline-block;
  margin-top: 0.5rem;
  padding: 0.2em 0.5em;
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 600;
}

.dsa-card__badge--easy { background: #d1fae5; color: #047857; }
.dsa-card__badge--medium { background: #fef3c7; color: #b45309; }
.dsa-card__badge--hard { background: #fee2e2; color: #b91c1c; }

.dsa-card__link {
  display: block;
  color: inherit;
  text-decoration: none;
}

.dsa-card__link:hover {
  color: var(--color-accent);
}

.dsa-card__link:hover .dsa-card__title {
  text-decoration: underline;
}

.dsa-card__link--block {
  cursor: default;
}

.dsa-card__link--block:hover .dsa-card__title {
  text-decoration: none;
}

.dsa-card__link--block:hover {
  color: inherit;
}

.dsa-card__open--impl {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  margin-top: 0.4rem;
  padding: 0.35rem 0.65rem;
  background: transparent;
  border: 1px solid var(--color-accent);
  border-radius: var(--radius-sm);
  transition: background 0.2s, color 0.2s;
  font-size: 0.8rem;
  color: var(--color-accent);
  font-weight: 500;
}
.dsa-card__open--impl::before {
  content: '';
  width: 0.85em;
  height: 0.85em;
  background: currentColor;
  mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='currentColor' stroke-width='2'%3E%3Cpath d='M18 13v6a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2V8a2 2 0 0 1 2-2h6'/%3E%3Cpolyline points='15 3 21 3 21 9'/%3E%3Cline x1='10' y1='14' x2='21' y2='3'/%3E%3C/svg%3E") no-repeat center;
  mask-size: contain;
  -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='currentColor' stroke-width='2'%3E%3Cpath d='M18 13v6a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2V8a2 2 0 0 1 2-2h6'/%3E%3Cpolyline points='15 3 21 3 21 9'/%3E%3Cline x1='10' y1='14' x2='21' y2='3'/%3E%3C/svg%3E") no-repeat center;
  -webkit-mask-size: contain;
}

.dsa-card__open--impl:hover {
  background: var(--color-accent);
  color: #fff;
  text-decoration: none;
}

.dsa-card__view-code {
  display: inline-block;
  margin-top: 0.35rem;
  font-size: 0.75rem;
  color: var(--color-text-muted);
  margin-left: 0.25rem;
}

.dsa-card__view-code:hover {
  color: var(--color-accent);
  text-decoration: underline;
}

.dsa-card__muted {
  display: block;
  margin-top: 0.5rem;
  font-size: 0.8rem;
  color: var(--color-text-muted);
}

.dsa-card__code-only-badge {
  display: inline-block;
  margin-top: 0.35rem;
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

.dsa-card__actions,
.dsa-card__actions-btn {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 0.5rem;
  padding: 0.5rem 0 0;
  border: none;
  border-top: 1px solid var(--color-border);
  background: transparent;
  cursor: pointer;
  min-height: 44px;
  width: 100%;
  text-align: left;
  font: inherit;
  color: inherit;
  transition: background 0.2s;
  box-sizing: border-box;
}
.dsa-card__actions-btn:hover {
  background: var(--color-bg);
}
.dsa-card__actions-btn:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.dsa-card__status-label {
  font-size: 0.8rem;
  color: var(--color-text-muted);
}

.dsa-card__done-icon {
  width: 20px;
  height: 20px;
  min-width: 20px;
  min-height: 20px;
  padding: 0;
  border: 1px solid var(--color-border);
  border-radius: 4px;
  background: var(--color-surface);
  font-size: 0.75rem;
  line-height: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s, border-color 0.2s;
  flex-shrink: 0;
}
@media (max-width: 767px) {
  .dsa-card__done-icon {
    width: 22px;
    height: 22px;
    min-width: 22px;
    min-height: 22px;
    font-size: 0.85rem;
  }
}

.dsa-card__actions-btn:hover .dsa-card__done-icon {
  background: var(--color-bg);
  border-color: var(--color-accent);
}

.dsa-card--done {
  background: var(--color-to-study-muted, #f0fdf4);
  border-color: var(--color-mastered, #22c55e);
}

.dsa-card--done .dsa-card__title {
  text-decoration: line-through;
  opacity: 0.85;
}

.dsa-card--done .dsa-card__done-icon {
  background: #059669;
  border-color: #059669;
  color: #fff;
  font-weight: 700;
  font-size: 0.85rem;
}
.dsa-card--done .dsa-card__actions-btn:hover .dsa-card__done-icon {
  background: #047857;
  border-color: #047857;
  color: #fff;
}

.dsa-card--revise {
  background: var(--color-revision-muted, #f5f3ff);
  border-color: var(--color-revision, #7c3aed);
}
.dsa-card--revise .dsa-card__done-icon {
  background: var(--color-revision-muted, #ede9fe);
  border-color: var(--color-revision);
  color: var(--color-revision);
}

.dsa-card__actions-btn.dsa-card__done--loading {
  opacity: 0.7;
  pointer-events: none;
}
.dsa-card__actions-btn:disabled {
  cursor: not-allowed;
}

.dsa-cards-error {
  margin: 0;
  padding: 1rem;
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

/* Implementations section */
.dsa-implementations {
  margin-top: 2.5rem;
  padding-top: 2rem;
  border-top: 1px solid var(--color-border);
}

.dsa-implementations__title {
  margin: 0 0 0.5rem;
  font-size: 1.25rem;
  font-weight: 700;
}

.dsa-implementations__subtitle {
  margin: 0 0 1rem;
  font-size: 0.95rem;
  color: var(--color-text-muted);
}

.dsa-implementations__filter-wrap {
  margin-bottom: 1rem;
}
.dsa-implementations__filter-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-text-muted);
  margin-bottom: 0.25rem;
}
.dsa-implementations__search {
  width: 100%;
  max-width: 280px;
  padding: 0.4rem 0.75rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
}

.dsa-implementations__empty-hint {
  margin: 0.5rem 0 0;
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

.dsa-implementations-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 1rem;
}

.dsa-implementations__block {
  border: 1px solid #E2E8F0;
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--color-surface);
  box-shadow: var(--dsa-shadow-card);
  transition: box-shadow 0.2s;
}
.dsa-implementations__block:hover {
  box-shadow: var(--dsa-shadow-card-hover);
}
.dsa-implementations__block.hidden {
  display: none !important;
}
.dsa-implementations__topic-toggle {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.65rem 1rem;
  border: none;
  background: var(--dsa-surface-gray, #F1F5F9);
  color: var(--color-text);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  text-align: left;
  transition: background 0.2s;
}
.dsa-implementations__topic-toggle:hover {
  background: var(--color-bg);
}
.dsa-implementations__topic-toggle:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: -2px;
}
.dsa-implementations__topic-chevron {
  color: var(--color-text-muted);
  transition: transform 0.25s ease;
}
.dsa-implementations__topic-chevron svg {
  width: 16px;
  height: 16px;
}
.dsa-implementations__block.is-open .dsa-implementations__topic-chevron {
  transform: rotate(180deg);
}
.dsa-implementations__block .dsa-implementations__files {
  padding: 1rem 1.25rem;
  margin: 0;
  border-top: 1px solid var(--color-border);
}
.dsa-implementations__block:not(.is-open) .dsa-implementations__files {
  display: none;
}

.dsa-implementations__topic {
  margin: 0 0 0.5rem;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-text);
}
.dsa-implementations__item.hidden {
  display: none !important;
}

.dsa-implementations__files {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem 0.75rem;
}

.dsa-implementations__item {
  margin: 0;
}

.dsa-implementations__link {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  padding: 0.4rem 0.75rem;
  border-radius: 999px;
  background: var(--dsa-surface-gray, #F1F5F9);
  color: var(--color-accent);
  text-decoration: none;
  font-size: 0.8125rem;
  font-weight: 500;
  transition: background 0.2s, color 0.2s;
  box-sizing: border-box;
}

.dsa-implementations__link:hover {
  background: var(--color-accent);
  color: #fff;
  text-decoration: none;
}

.dsa-implementations__empty {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

.dsa-implementations__snippet-wrap {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem 0.75rem;
}

.dsa-implementations__snippet-wrap .dsa-implementations__link {
  margin: 0;
}

.dsa-implementations__snippet-badge {
  font-size: 0.65rem;
  font-weight: 600;
  padding: 0.2rem 0.45rem;
  border-radius: 999px;
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

.dsa-implementations__snippet-badge--code-only {
  background: var(--color-to-study-muted);
  color: var(--color-text-muted);
}

.dsa-implementations__snippet-badge--link {
  background: var(--color-accent-muted, rgba(59, 130, 246, 0.15));
  color: var(--color-accent);
}

.dsa-implementations__open-link {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  padding: 0.35rem 0.65rem;
  border-radius: 999px;
  background: var(--dsa-surface-gray, #F1F5F9);
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--color-accent);
  text-decoration: none;
  transition: background 0.2s, color 0.2s;
  box-sizing: border-box;
}

.dsa-implementations__open-link:hover {
  background: var(--color-accent);
  color: #fff;
  text-decoration: none;
}

/* DSA code viewer page */
.main--dsa-code {
  max-width: 900px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
}

.dsa-code-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.dsa-code-bar__back {
  color: var(--color-accent);
  text-decoration: none;
  font-weight: 500;
}

.dsa-code-bar__back:hover {
  text-decoration: underline;
}

.dsa-code-bar__external-link {
  font-size: 0.9rem;
  color: var(--color-accent);
  text-decoration: none;
  font-weight: 500;
}

.dsa-code-bar__external-link:hover {
  text-decoration: underline;
}

.dsa-code-bar__external-link.hidden {
  display: none !important;
}

.dsa-code-loading {
  padding: 2rem;
  text-align: center;
  color: var(--color-text-muted);
}

.dsa-code-error {
  padding: 1rem;
  background: #fee2e2;
  color: #991b1b;
  border-radius: var(--radius);
}

.dsa-code-error.hidden {
  display: none !important;
}

.dsa-code-content {
  background: var(--color-to-study-muted);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1rem 1.25rem;
  overflow-x: auto;
  font-size: 0.875rem;
  line-height: 1.5;
}

.dsa-code-content.hidden {
  display: none !important;
}

.dsa-code-content code {
  font-family: ui-monospace, monospace;
  white-space: pre;
}