/*
 * sd-card — card family (core sample Session 2.2; all variants and states Session 2.3; owner amendments D-026)
 * Variants: service (index number), product (1:1 image, category label, code chip), article (16:9 media, meta),
 *           category (illustration + count), information (not a link, no hover), featured (white, blue top line)
 * States: default, hover (stronger border, lift, arrow moves), focus-visible (ring around the whole card), active
 * Structure through borders and space, not shadows (Design_System_Plan.md 6.3).
 * The whole card is one link (stretched link on the title) — one tab stop, readable link name.
 * Responsive inside the component with a container query (Design_System_Plan.md 10.7).
 */

.sd-card {
  position: relative;
  display: flex;
  flex-direction: column;
  container-type: inline-size;
  height: 100%;
  background: var(--sd-color-card-bg);
  border: var(--sd-border-width) solid var(--sd-color-card-border);
  border-radius: var(--sd-radius-md);
  transition: border-color var(--sd-transition-feedback), transform var(--sd-transition-ui);
}

.sd-card__media {
  position: relative;
  aspect-ratio: 1 / 1;
  overflow: hidden;
  background: var(--sd-color-white);
  border-bottom: var(--sd-border-width) solid var(--sd-color-card-divider);
  border-radius: var(--sd-radius-md) var(--sd-radius-md) 0 0;
}

.sd-card__media img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  transition: transform var(--sd-transition-reveal);
}

.sd-card__body {
  display: flex;
  flex: 1;
  flex-direction: column;
  gap: var(--sd-space-3);
  padding: var(--sd-space-4);
}

@container (min-width: 22rem) {
  .sd-card__body { padding: var(--sd-space-5); }
}

.sd-card__title {
  font-size: var(--sd-font-size-h4);
  line-height: var(--sd-line-height-h4);
  font-weight: var(--sd-font-weight-semibold);
  letter-spacing: var(--sd-letter-spacing-heading);
  color: var(--sd-color-text-heading);
}

.sd-card__title a {
  color: inherit;
  text-decoration: none;
}

/* Stretched link: the whole card is clickable */
.sd-card__title a::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
}

.sd-card__text {
  color: var(--sd-color-text-muted);
  font-size: var(--sd-font-size-small);
  line-height: var(--sd-line-height-small);
}

.sd-card__meta {
  font-size: var(--sd-font-size-small);
  color: var(--sd-color-text-muted);
}

.sd-card__footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sd-space-3);
  margin-top: auto;
  padding-top: var(--sd-space-3);
  font-size: var(--sd-font-size-ui);
  font-weight: var(--sd-font-weight-medium);
  color: var(--sd-color-card-action);
}

.sd-card__arrow {
  width: 1.25rem;
  height: 1.25rem;
  flex: none;
  transition: transform var(--sd-transition-ui);
}

/* Index number for system cards (e.g. service 01–05) */
.sd-card__index {
  font-size: var(--sd-font-size-label);
  font-weight: var(--sd-font-weight-medium);
  letter-spacing: var(--sd-letter-spacing-label);
  color: var(--sd-color-card-index);
  font-variant-numeric: tabular-nums;
}

/* Hover / focus: blue border, title underline, arrow moves; image moves calmly */
.sd-card:hover,
.sd-card:focus-within,
.sd-card[data-state="hover"] {
  box-shadow: inset 0 0 0 1px var(--sd-color-card-border);  /* border reads as 2px */
}

.sd-card:hover .sd-card__title a,
.sd-card[data-state="hover"] .sd-card__title a {
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
}

.sd-card:hover,
.sd-card[data-state="hover"] { transform: translateY(-2px); }

.sd-card:hover .sd-card__arrow,
.sd-card[data-state="hover"] .sd-card__arrow { transform: translateX(0.25rem); }

.sd-card:hover .sd-card__media img,
.sd-card[data-state="hover"] .sd-card__media img { transform: scale(1.03); }

/* Focus ring around the whole card (the link inside has focus) */
.sd-card:has(a:focus-visible),
.sd-card[data-state="focus"] {
  outline: var(--sd-focus-ring-width) solid var(--sd-focus-ring-color);
  outline-offset: var(--sd-focus-ring-offset);
}

/* Without :has() support the link keeps its own focus ring */
@supports selector(:has(a)) {
  .sd-card__title a:focus-visible { outline: none; }
}

/* Product variant: product photo on white (photos keep their own colours, Blueprint 3.17), code in tabular figures */
.sd-card--product .sd-card__media img { padding: var(--sd-space-4); }

.sd-card__code {
  align-self: flex-start;
  padding: 0.125rem var(--sd-space-2);
  border: var(--sd-border-width) solid var(--sd-color-card-divider);
  border-radius: var(--sd-radius-sm);
  background: var(--sd-color-white);
  font-size: var(--sd-font-size-small);
  font-weight: var(--sd-font-weight-medium);
  color: var(--sd-color-text-default);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.02em;
}

/* The code moves to the next line as a whole (a short code such as TN-1201A never splits at its hyphen); a long code
   still wraps inside its own box (Session 9.2, R-3). */
.sd-card__code-value { display: inline-block; max-width: 100%; }

/* Featured variant (e.g. the flagship service): white surface, blue border and top line */
.sd-card--featured {
  background: var(--sd-color-white);
  box-shadow: inset 0 3px 0 var(--sd-color-card-border);
}

.sd-card--featured:hover,
.sd-card--featured[data-state="hover"] {
  box-shadow: inset 0 3px 0 var(--sd-color-card-border), inset 0 0 0 1px var(--sd-color-card-border);
}


.sd-card:active,
.sd-card[data-state="active"] { transform: none; }

/* Article variant: 16:9 media (cover photo or neutral placeholder), meta line, "Read Article" */
.sd-card--article .sd-card__media { aspect-ratio: 16 / 9; }
.sd-card--article .sd-card__media img { object-fit: cover; }

.sd-card__meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sd-space-1) var(--sd-space-3);
}

/* Missing image: neutral line placeholder, never a photorealistic fake (CLAUDE.md 7; Design_System_Plan.md 10.9) */
.sd-card__placeholder {
  display: grid;
  place-items: center;
  width: 100%;
  height: 100%;
  color: var(--sd-color-blue-700);
  background: var(--sd-color-white);
}

.sd-card__placeholder svg { width: 3rem; height: 3rem; }

/* Category variant: illustration on white, item count */
.sd-card--category .sd-card__media { aspect-ratio: 4 / 3; }
.sd-card--category .sd-card__media img { padding: var(--sd-space-4); }

/* Information variant: content only (no link, no lift); icon + title + text */
.sd-card--info {
  background: var(--sd-color-surface);
  border-color: var(--sd-color-border-subtle);
}

.sd-card--info:hover { transform: none; box-shadow: none; }

.sd-card__icon {
  width: 2rem;
  height: 2rem;
  color: var(--sd-color-brand-blue);
}

/* Small inline status marker inside a card (sd-badge in badge.css stays above the stretched link) */
.sd-card .sd-badge { position: relative; z-index: 2; }

@media (prefers-reduced-motion: reduce) {
  .sd-card:hover,
  .sd-card[data-state="hover"] { transform: none; }
}

/* ---------- Tile: square category card without description (Session 4.3 follow-up, owner choice option D — D-036) ----------
   Number (copper) and name at the top left, illustration below. Hover and keyboard focus: light blue surface, the picture
   rises a little, "Explore →" appears under the name (always visible on touch screens; hidden on narrow tiles).
   The whole tile is one link (stretched link on the name). Used for the six Instruments categories (Products, Instruments).
   Row: ul.sd-tiles — 2 per row on phones, 3 from 640px; beside a section header from 1024px both rows fit one laptop screen. */
.sd-tiles { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--sd-space-3); margin: 0; padding: 0; list-style: none; }
.sd-tiles > li { display: grid; }
@media (min-width: 640px) { .sd-tiles { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--sd-space-4); } }

.sd-tile {
  position: relative;
  display: grid;
  aspect-ratio: 1 / 1;
  overflow: hidden;
  container-type: inline-size;
  background: var(--sd-color-white);
  border: var(--sd-border-width) solid var(--sd-color-card-divider);
  border-radius: var(--sd-radius-md);
  transition: background-color var(--sd-transition-feedback), border-color var(--sd-transition-feedback);
}
.sd-tile__media { grid-area: 1 / 1; display: grid; place-items: center; }
.sd-tile__media img { width: 100%; height: 100%; object-fit: contain; padding-top: 30%; transition: transform var(--sd-transition-reveal); }
.sd-tile__head { grid-area: 1 / 1; align-self: start; display: grid; gap: var(--sd-space-1); padding: var(--sd-space-4); }
.sd-tile__index { font-size: var(--sd-font-size-label); font-weight: var(--sd-font-weight-medium); color: var(--sd-color-accent-copper-text); font-variant-numeric: tabular-nums; }
.sd-tile__title { margin: 0; color: var(--sd-color-text-heading); font-size: clamp(1rem, 10cqi, var(--sd-font-size-h3)); font-weight: var(--sd-font-weight-semibold); letter-spacing: var(--sd-letter-spacing-heading); line-height: 1.1; }
.sd-tile__title a { color: inherit; text-decoration: none; }
.sd-tile__title a::after { content: ""; position: absolute; inset: 0; z-index: 1; }
.sd-tile__more { display: inline-flex; align-items: center; gap: var(--sd-space-1); font-size: var(--sd-font-size-small); font-weight: var(--sd-font-weight-medium); color: var(--sd-color-brand-blue); opacity: 0; transform: translateY(-0.25rem); transition: opacity var(--sd-transition-ui), transform var(--sd-transition-ui); }
.sd-tile__more svg { width: 1rem; height: 1rem; }

.sd-tile:hover, .sd-tile:focus-within { background: var(--sd-color-blue-050); border-color: var(--sd-color-brand-blue); }
.sd-tile:hover .sd-tile__media img, .sd-tile:focus-within .sd-tile__media img { transform: translateY(-3%); mix-blend-mode: multiply; }
.sd-tile:hover .sd-tile__more, .sd-tile:focus-within .sd-tile__more { opacity: 1; transform: none; }
.sd-tile:has(a:focus-visible) { outline: var(--sd-focus-ring-width) solid var(--sd-focus-ring-color); outline-offset: var(--sd-focus-ring-offset); }
@supports selector(:has(a)) { .sd-tile__title a:focus-visible { outline: none; } }
@media (hover: none) { .sd-tile__more { opacity: 1; transform: none; } }

@container (max-width: 14rem) {
  .sd-tile__head { padding: var(--sd-space-3); }
  .sd-tile__more { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  .sd-tile, .sd-tile * { transition: none !important; }
  .sd-tile:hover .sd-tile__media img, .sd-tile:focus-within .sd-tile__media img { transform: none; }
}