/* ==========================================================================
   Blueprint Biologics, Utilities and Base
   Phase 1 foundation. Reusable, framework-agnostic classes.
   Requires tokens.css to be loaded first.
   ========================================================================== */

/* --- Reset and base ------------------------------------------------------ */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  line-height: var(--lh-body);
  color: var(--text-body);
  background: var(--bg-base);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden; /* guard against horizontal overflow */
}

img,
picture,
svg,
video {
  display: block;
  max-width: 100%;
  height: auto;
}

h1, h2, h3, h4 {
  margin: 0;
  font-weight: 700;
  line-height: var(--lh-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--text-strong);
}

p {
  margin: 0;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

/* --- Accessibility ------------------------------------------------------- */
:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
  border-radius: var(--radius-sm);
}

.u-visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.u-skip-link {
  position: absolute;
  left: var(--space-3);
  top: -100px;
  background: var(--accent);
  color: #fff;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-sm);
  transition: top var(--dur-fast) var(--ease);
}

.u-skip-link:focus {
  top: var(--space-3);
}

/* --- Layout -------------------------------------------------------------- */
.u-container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.u-container--wide {
  max-width: var(--container-wide);
}

.u-section {
  padding-block: var(--section-pad-y);
}

.u-section--soft {
  background: var(--bg-soft);
}

.u-section--dark {
  background: var(--surface-dark);
  color: var(--text-on-dark);
}

/* Blueprint grid background texture, low contrast, decorative only */
.u-grid-bg {
  background-image:
    linear-gradient(var(--bg-grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--bg-grid) 1px, transparent 1px);
  background-size: 32px 32px;
}

/* --- Responsive grid ----------------------------------------------------- */
.u-grid {
  display: grid;
  gap: var(--space-5);
  grid-template-columns: 1fr;
}

@media (min-width: 768px) {
  .u-grid--2,
  .u-grid--3,
  .u-grid--4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .u-grid--3 {
    grid-template-columns: repeat(3, 1fr);
  }
  .u-grid--4 {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* --- Flex helpers -------------------------------------------------------- */
.u-flex {
  display: flex;
  gap: var(--space-3);
}

.u-flex--between {
  justify-content: space-between;
  align-items: center;
}

.u-flex--center {
  justify-content: center;
  align-items: center;
}

.u-flex--wrap {
  flex-wrap: wrap;
}

/* --- Typography helpers -------------------------------------------------- */
.u-eyebrow {
  font-size: var(--fs-small);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: var(--tracking-eyebrow);
  color: var(--accent);
}

.u-display { font-size: var(--fs-display); }
.u-h1 { font-size: var(--fs-h1); }
.u-h2 { font-size: var(--fs-h2); }
.u-h3 { font-size: var(--fs-h3); }

.u-text-muted { color: var(--text-muted); }
.u-text-center { text-align: center; }

/* Constrain body text line length for readability */
.u-measure {
  max-width: 65ch;
}

/* Mono, technical labels only, SKUs, dosages, catalog metadata */
.u-mono {
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
}

/* --- Buttons ------------------------------------------------------------- */
.u-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  min-height: 44px;
  padding: var(--space-3) var(--space-5);
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  font-weight: 600;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: background-color var(--dur-fast) var(--ease),
              transform var(--dur-fast) var(--ease),
              border-color var(--dur-fast) var(--ease);
}

.u-btn:hover {
  text-decoration: none;
}

.u-btn--primary {
  background: var(--accent);
  color: #fff;
}

.u-btn--primary:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
}

.u-btn--primary:active {
  transform: translateY(0);
}

.u-btn--secondary {
  background: transparent;
  border-color: var(--border-strong);
  color: var(--text-strong);
}

.u-btn--secondary:hover {
  background: var(--bg-muted);
}

.u-btn--ghost {
  background: transparent;
  color: var(--accent);
}

.u-btn--ghost:hover {
  background: var(--accent-soft);
}

.u-btn:disabled,
.u-btn[aria-disabled="true"] {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

/* --- Cards --------------------------------------------------------------- */
.u-card {
  background: var(--bg-base);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--dur-mid) var(--ease),
              transform var(--dur-mid) var(--ease);
}

.u-card--hover:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

/* Use sparingly, hero and feature highlights only. Solid fallback first. */
.u-card--glass {
  background: var(--bg-soft);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
}

@supports ((backdrop-filter: blur(10px)) or (-webkit-backdrop-filter: blur(10px))) {
  .u-card--glass {
    background: rgba(255, 255, 255, 0.7);
    border-color: rgba(255, 255, 255, 0.6);
    -webkit-backdrop-filter: blur(10px);
    backdrop-filter: blur(10px);
  }
}

/* --- Badges and pills ---------------------------------------------------- */
.u-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-1) var(--space-3);
  font-size: var(--fs-small);
  font-weight: 600;
  border-radius: var(--radius-pill);
  background: var(--accent-soft);
  color: var(--accent);
}

/* --- Compliance strip ---------------------------------------------------- */
.u-compliance-strip {
  font-size: var(--fs-small);
  color: var(--text-muted);
  background: var(--bg-muted);
  border-block: 1px solid var(--border);
  padding-block: var(--space-2);
  text-align: center;
}

/* Short research-use disclaimer line for catalog cards */
.u-disclaimer-note {
  font-size: var(--fs-small);
  color: var(--text-muted);
}

/* --- Forms --------------------------------------------------------------- */
.u-field {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  margin-bottom: var(--space-5);
}

.u-label {
  font-size: var(--fs-small);
  font-weight: 600;
  color: var(--text-strong);
}

.u-input,
.u-textarea,
.u-select {
  width: 100%;
  min-height: 44px;
  padding: var(--space-3);
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  color: var(--text-body);
  background: var(--bg-base);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  transition: border-color var(--dur-fast) var(--ease),
              box-shadow var(--dur-fast) var(--ease);
}

.u-input:focus-visible,
.u-textarea:focus-visible,
.u-select:focus-visible {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.u-textarea {
  min-height: 120px;
  resize: vertical;
}

.u-field--error .u-input,
.u-field--error .u-textarea {
  border-color: var(--danger);
}

.u-error-text {
  font-size: var(--fs-small);
  color: var(--danger);
}

.u-help-text {
  font-size: var(--fs-small);
  color: var(--text-muted);
}

/* --- Scroll reveal ------------------------------------------------------- */
/* Pair with a small IntersectionObserver that adds .is-visible */
.u-reveal {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity var(--dur-mid) var(--ease),
              transform var(--dur-mid) var(--ease);
}

.u-reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* --- Reduced motion ------------------------------------------------------ */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  .u-reveal {
    opacity: 1;
    transform: none;
  }
}