/* ==========================================================================
   Case Library
   Page-local styles only. Palette, type, shell, navbar, buttons, chips,
   eyebrow and the 44px touch-target rules all come from tokens.css.

   Breakpoints, and nothing else: 1200px, 900px, 640px.
   ========================================================================== */

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: inherit;
  text-decoration: none;
}

.page-main {
  flex: 1;
  padding: 44px 0 72px;
}

/* --- Header --------------------------------------------------------------- */

.lib-head {
  max-width: 640px;
  margin-bottom: 32px;
}

.lib-title {
  margin: 14px 0 12px;
  font-family: var(--font-serif);
  font-size: clamp(2rem, 4vw, 2.875rem);
  font-weight: 500;
  line-height: 1.08;
  letter-spacing: -0.03em;
  color: var(--ink-primary);
}

.lib-lede {
  font-size: 1rem;
  line-height: 1.6;
  color: var(--ink-secondary);
}

.lib-scale {
  margin-top: 10px;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--ink-muted);
}

/* --- Controls ------------------------------------------------------------- */

.controls {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-bottom: 28px;
}

.search-row {
  display: flex;
  align-items: stretch;
  gap: 10px;
}

.search-field {
  position: relative;
  display: flex;
  align-items: center;
  flex: 1 1 auto;
  min-width: 0;
}

.search-glyph {
  position: absolute;
  left: 15px;
  width: 17px;
  height: 17px;
  color: var(--ink-muted);
  pointer-events: none;
}

.search-input {
  width: 100%;
  min-width: 0;
  height: 50px;
  padding: 0 52px 0 43px;
  border: 1px solid var(--line-base);
  border-radius: var(--r-md);
  background: var(--surface-raised);
  color: var(--ink-primary);
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  outline: none;
  box-shadow: var(--shadow-xs);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.search-input::-webkit-search-cancel-button {
  appearance: none;
}

.search-input:focus {
  border-color: var(--brand-primary);
  box-shadow: 0 0 0 3px var(--brand-tint);
}

/* Real button, real name, 44px target, own focus ring. */
.search-clear {
  position: absolute;
  right: 3px;
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 0;
  border-radius: var(--r-pill);
  background: transparent;
  color: var(--ink-muted);
  cursor: pointer;
  transition: color var(--transition-fast);
}

.search-clear svg {
  width: 26px;
  height: 26px;
  padding: 5px;
  border-radius: var(--r-pill);
  background: var(--bg-subtle);
  transition: background var(--transition-fast);
}

.search-clear:hover {
  color: var(--ink-primary);
}

.search-clear:hover svg {
  background: var(--brand-light);
}

.search-clear:active svg {
  background: var(--brand-tint-hover);
}

.filters-toggle {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  flex: none;
  min-height: 50px;
  padding: 0 16px;
  border: 1px solid var(--line-base);
  border-radius: var(--r-md);
  background: var(--surface-raised);
  color: var(--ink-primary);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 650;
  cursor: pointer;
  box-shadow: var(--shadow-xs);
  transition: border-color var(--transition-fast), background var(--transition-fast);
}

.filters-toggle svg {
  width: 17px;
  height: 17px;
  flex: none;
}

.filters-toggle:hover {
  border-color: var(--line-strong);
  background: var(--bg-subtle);
}

.filters-toggle[aria-expanded="true"] {
  border-color: var(--brand-primary);
  color: var(--brand-primary);
}

.filters-count {
  display: inline-grid;
  place-items: center;
  min-width: 20px;
  height: 20px;
  padding: 0 6px;
  border-radius: var(--r-pill);
  background: var(--brand-primary);
  color: var(--brand-on);
  font-size: 0.6875rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}

/* --- View switch and sort ------------------------------------------------ */

.view-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}

.view-switch {
  display: flex;
  align-items: center;
  gap: 2px;
  padding: 3px;
  border: 1px solid var(--line-base);
  border-radius: var(--r-pill);
  background: var(--bg-subtle);
  max-width: 100%;
  overflow-x: auto;
  scrollbar-width: none;
}

.view-switch::-webkit-scrollbar {
  display: none;
}

.view-tab {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: none;
  min-height: 40px;
  padding: 0 15px;
  border: 0;
  border-radius: var(--r-pill);
  background: transparent;
  color: var(--ink-secondary);
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  font-weight: 650;
  white-space: nowrap;
  cursor: pointer;
  transition: background var(--transition-fast), color var(--transition-fast);
}

/* Compact 40px pill, 44px hit area, same trick tokens.css uses on chips. */
.view-tab::before {
  content: "";
  position: absolute;
  inset: 50% 0 auto 0;
  transform: translateY(-50%);
  height: 44px;
}

.view-tab:hover {
  color: var(--ink-primary);
}

.view-tab.is-active {
  background: var(--surface-raised);
  color: var(--brand-primary);
  box-shadow: var(--shadow-xs);
}

.select {
  min-height: 46px;
  padding: 0 34px 0 14px;
  border: 1px solid var(--line-base);
  border-radius: var(--r-md);
  background: var(--surface-raised);
  color: var(--ink-primary);
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  font-weight: 600;
  cursor: pointer;
  outline: none;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%236b7a74' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
}

.select:focus {
  border-color: var(--brand-primary);
}

.select-block {
  width: 100%;
  max-width: 320px;
}

/* --- Filters panel ------------------------------------------------------- */

.filters-scrim {
  display: none;
}

.filters-panel {
  padding: 18px 20px 16px;
  border: 1px solid var(--line-strong);
  border-radius: var(--r-lg);
  background: var(--surface-raised);
  box-shadow: var(--shadow-md);
}

.filters-panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 14px;
}

.filters-panel-title {
  font-size: 0.8125rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-muted);
}

.filters-close {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  margin: -10px -10px -10px 0;
  border: 0;
  border-radius: var(--r-pill);
  background: transparent;
  color: var(--ink-muted);
  cursor: pointer;
}

.filters-close svg {
  width: 18px;
  height: 18px;
}

.filters-close:hover {
  color: var(--ink-primary);
}

.filters-panel-body {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.filter-group {
  min-width: 0;
  padding: 0;
  border: 0;
}

.filter-legend {
  padding: 0;
  margin-bottom: 10px;
  font-size: 0.8125rem;
  font-weight: 700;
  color: var(--ink-primary);
}

.filter-hint {
  margin: -6px 0 10px;
  font-size: 0.75rem;
  color: var(--ink-muted);
}

.filter-group-quiet {
  padding-top: 14px;
  border-top: 1px dashed var(--line-dashed);
}

.filter-group-quiet .filter-legend {
  color: var(--ink-secondary);
}

/* 14px row gap keeps the 44px hit areas from overlapping between rows. */
.chip-set {
  display: flex;
  flex-wrap: wrap;
  gap: 14px 8px;
}

/* Compact pill, 44px target. tokens.css grows .filter-chip with a pseudo
   element, so only the look is defined here. */
.filter-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  min-height: 34px;
  padding: 0 13px;
  border: 1px solid var(--line-base);
  border-radius: var(--r-pill);
  background: var(--surface-raised);
  color: var(--ink-secondary);
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  font-weight: 600;
  white-space: nowrap;
  cursor: pointer;
  transition: background var(--transition-fast), color var(--transition-fast), border-color var(--transition-fast);
}

.filter-chip:hover {
  border-color: var(--line-strong);
  background: var(--bg-subtle);
  color: var(--ink-primary);
}

.filter-chip[aria-pressed="true"] {
  border-color: var(--brand-primary);
  background: var(--brand-primary);
  color: var(--brand-on);
}

.filter-chip-count {
  font-size: 0.6875rem;
  font-variant-numeric: tabular-nums;
  opacity: 0.62;
}

.filters-panel-foot {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 10px;
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid var(--line-subtle);
}

/* --- Results line -------------------------------------------------------- */

.results-row {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.results-line {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--ink-muted);
}

.results-reset {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0;
  border: 0;
  background: none;
  color: var(--brand-primary);
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  font-weight: 650;
  text-decoration: underline;
  text-underline-offset: 3px;
  cursor: pointer;
}

/* --- Recommended next rail ---------------------------------------------- */

.rail {
  margin-bottom: 34px;
  padding-bottom: 30px;
  border-bottom: 1px solid var(--line-subtle);
}

.rail-head {
  margin-bottom: 16px;
}

.rail-title {
  font-family: var(--font-serif);
  font-size: 1.375rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--ink-primary);
}

.rail-note {
  margin-top: 4px;
  font-size: 0.8125rem;
  color: var(--ink-muted);
}

.rail-track {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(280px, 100%), 1fr));
  gap: 16px;
}

/* --- Cases grid --------------------------------------------------------- */

.cases-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(300px, 100%), 1fr));
  gap: 18px;
}

/* The library can take a moment to personalise. Case-shaped placeholders make
   that wait legible without a decorative spinner that can be distorted by a
   browser or cached stylesheet. */
.cases-loading {
  display: contents;
}

.case-skeleton {
  min-height: 276px;
  border: 1px solid var(--line-base);
  border-radius: var(--r-lg);
  background:
    linear-gradient(var(--paper-deep), var(--paper-deep)) 20px 22px / 38% 10px no-repeat,
    linear-gradient(var(--paper-deep), var(--paper-deep)) 20px 56px / 68% 24px no-repeat,
    linear-gradient(var(--paper-deep), var(--paper-deep)) 20px 112px / 88% 9px no-repeat,
    linear-gradient(var(--paper-deep), var(--paper-deep)) 20px 132px / 72% 9px no-repeat,
    linear-gradient(var(--paper-deep), var(--paper-deep)) 20px calc(100% - 48px) / 34% 30px no-repeat,
    var(--surface-raised);
  box-shadow: var(--shadow-xs);
}

/* One result used to sit in the left third of a three-column grid. A single
   hit gets a wider card plus a deliberate companion panel instead. */
.cases-grid[data-density="single"] {
  grid-template-columns: minmax(0, 600px) minmax(0, 300px);
  align-items: start;
}

.cases-grid[data-density="pair"] {
  grid-template-columns: repeat(2, minmax(min(300px, 100%), 430px));
}

.cases-grid[data-density="empty"] {
  grid-template-columns: minmax(0, 1fr);
}

.grid-state {
  grid-column: 1 / -1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  padding: 64px 20px;
  border: 1px dashed var(--line-dashed);
  border-radius: var(--r-lg);
  color: var(--ink-muted);
  text-align: center;
}

.grid-state-title {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--ink-primary);
}

.grid-state p {
  font-size: 0.875rem;
  max-width: 42ch;
}

/* --- Case card ---------------------------------------------------------- */

.case-card {
  position: relative;
  display: flex;
  flex-direction: column;
  min-width: 0;
  padding: 18px 20px 20px;
  border: 1px solid var(--line-base);
  border-radius: var(--r-lg);
  background: var(--surface-raised);
  box-shadow: var(--shadow-xs);
  transition: border-color var(--transition-base), box-shadow var(--transition-base), transform var(--transition-base);
}

.case-card:hover,
.case-card:focus-within {
  transform: translateY(-2px);
  border-color: var(--brand-primary);
  box-shadow: var(--shadow-card);
}

/* Progress reads on the card edge before any text is parsed. */
.case-card[data-state="in_progress"] {
  border-left: 3px solid var(--gold-primary);
}

.case-card[data-state="solved"] {
  border-left: 3px solid var(--brand-primary);
}

.case-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 10px;
}

.case-kind {
  display: flex;
  align-items: center;
  gap: 8px;
  flex: 1 1 auto;
  flex-wrap: wrap;
  min-width: 0;
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.07em;
  text-transform: uppercase;
}

.case-type {
  color: var(--brand-primary);
}

.case-level {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  color: var(--ink-muted);
}

.case-level::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: currentColor;
}

.case-level-foundation { color: var(--status-info); }
.case-level-intermediate { color: var(--gold-deep); }
.case-level-advanced { color: var(--status-danger); }

.case-state {
  flex: none;
  padding: 2px 8px;
  border-radius: var(--r-pill);
  font-size: 0.625rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  white-space: nowrap;
}

.case-state-in_progress {
  background: var(--gold-light);
  color: var(--gold-deep);
}

.case-state-solved {
  background: var(--brand-light);
  color: var(--brand-primary);
}

.case-name {
  font-family: var(--font-serif);
  font-size: 1.3125rem;
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--ink-primary);
  margin-bottom: 7px;
}

/* The real decision question, three lines at most in the dense grid. */
.case-question {
  font-size: 0.875rem;
  line-height: 1.5;
  color: var(--ink-secondary);
  margin-bottom: 14px;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.case-origin {
  margin-top: auto;
  padding-top: 12px;
  border-top: 1px solid var(--line-subtle);
  font-size: 0.75rem;
  color: var(--ink-muted);
}

.case-foot {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 12px;
}

.case-secondary {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  color: var(--ink-secondary);
  font-size: 0.8125rem;
  font-weight: 650;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.case-secondary:hover {
  color: var(--brand-primary);
}

.case-skills {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 14px;
}

.case-skill {
  padding: 3px 8px;
  border-radius: var(--r-xs);
  background: var(--bg-subtle);
  color: var(--ink-secondary);
  font-size: 0.6875rem;
  font-weight: 600;
}

.case-reason {
  margin-bottom: 12px;
  font-size: 0.8125rem;
  line-height: 1.45;
  color: var(--gold-deep);
}

/* Rail and single-result cards have room to breathe, so the question is
   not clamped and the skills are worth showing. */
.case-card-wide .case-name {
  font-size: 1.5rem;
}

.case-card-wide .case-question {
  display: block;
  font-size: 0.9375rem;
  overflow: visible;
}

/* --- Companion panel for a single result -------------------------------- */

.nudge {
  padding: 18px 20px;
  border: 1px dashed var(--line-dashed);
  border-radius: var(--r-lg);
  background: var(--bg-subtle);
}

.nudge-title {
  font-size: 0.8125rem;
  font-weight: 700;
  color: var(--ink-primary);
  margin-bottom: 4px;
}

.nudge-note {
  font-size: 0.75rem;
  line-height: 1.5;
  color: var(--ink-muted);
  margin-bottom: 10px;
}

.nudge-list {
  display: flex;
  flex-direction: column;
}

.nudge-list a,
.nudge-list button {
  display: flex;
  align-items: center;
  min-height: 44px;
  padding: 0;
  border: 0;
  background: none;
  color: var(--brand-primary);
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  font-weight: 650;
  text-align: left;
  cursor: pointer;
}

.nudge-list a:hover,
.nudge-list button:hover {
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* --- Card primary action ------------------------------------------------ */
/* Stretched over the whole card, so the target is the card, not the pill. */
.btn-start-case {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  min-height: 44px;
  padding: 0 18px;
  border: 1px solid var(--brand-primary);
  border-radius: var(--r-pill);
  background: var(--brand-primary);
  color: #ffffff;
  font-size: 0.8125rem;
  font-weight: 650;
  transition: background var(--transition-fast), border-color var(--transition-fast);
}

.btn-start-case::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: var(--r-lg);
}

.btn-start-case:hover,
.case-card:hover .btn-start-case {
  background: var(--brand-lift);
  border-color: var(--brand-lift);
}

.btn-reset-case {
  position: relative;
  z-index: 1;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0;
  border: 0;
  background: none;
  color: var(--ink-muted);
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  font-weight: 600;
  cursor: pointer;
}

.btn-reset-case:hover {
  color: var(--status-danger);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.btn-reset-case[disabled] {
  opacity: 0.5;
  cursor: default;
}

/* Controls the stretched action must not swallow. Non-interactive card
   content stays underneath so a tap anywhere still opens the case. */
.case-secondary,
.nudge-list a,
.nudge-list button {
  position: relative;
  z-index: 1;
}

/* --- Responsive --------------------------------------------------------- */

@media (max-width: 1200px) {
  .cases-grid {
    grid-template-columns: repeat(auto-fill, minmax(min(280px, 100%), 1fr));
  }
}

@media (max-width: 900px) {
  .page-main {
    padding: 32px 0 56px;
  }

  .cases-grid[data-density="single"],
  .cases-grid[data-density="pair"] {
    grid-template-columns: minmax(0, 1fr);
  }

  .view-row {
    align-items: stretch;
  }

  .view-switch {
    flex: 1 1 240px;
  }

  .sort-field .select {
    width: 100%;
  }
}

@media (max-width: 640px) {
  .lib-head {
    margin-bottom: 26px;
  }

  .cases-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .search-row {
    flex-wrap: wrap;
  }

  .filters-toggle {
    flex: 1 1 auto;
    justify-content: center;
  }

  .view-row {
    flex-direction: column;
    align-items: stretch;
  }

  .sort-field .select {
    width: 100%;
  }

  /* Compact sheet rather than a panel that pushes the grid down a screen. */
  .filters-scrim:not(.hidden) {
    display: block;
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    z-index: 120;
    background: rgba(0, 0, 0, 0.42);
  }

  .filters-panel {
    position: fixed;
    top: auto;
    right: 0;
    bottom: 0;
    left: 0;
    z-index: 130;
    max-height: 86vh;
    overflow-y: auto;
    padding: 16px 18px 20px;
    border: 0;
    border-top: 1px solid var(--line-strong);
    border-radius: var(--r-lg) var(--r-lg) 0 0;
    box-shadow: var(--shadow-xl);
  }

  .filters-panel-foot {
    position: sticky;
    bottom: -20px;
    padding-bottom: 4px;
    background: var(--surface-raised);
  }

  .select-block {
    max-width: none;
  }
}