/* ==========================================================================
   HERBALISSA UTILITIES
   Surface classes, layout helpers, and design system building blocks
   ========================================================================== */

/* ------------------------------------------------------------------
   SURFACES — "Stacked fine papers" tonal hierarchy
   Use these instead of borders to create visual separation
   ------------------------------------------------------------------ */

.surface                  { background-color: var(--color-surface); }
.surface-bright           { background-color: var(--color-surface-bright); }
.surface-dim              { background-color: var(--color-surface-dim); }
.surface-container-lowest { background-color: var(--color-surface-container-lowest); }
.surface-container-low    { background-color: var(--color-surface-container-low); }
.surface-container        { background-color: var(--color-surface-container); }
.surface-container-high   { background-color: var(--color-surface-container-high); }
.surface-container-highest{ background-color: var(--color-surface-container-highest); }
.surface-inverse          { background-color: var(--color-inverse-surface); color: var(--color-inverse-on-surface); }
.surface-primary          { background-color: var(--color-primary); color: var(--color-on-primary); }


/* ------------------------------------------------------------------
   GLASSMORPHISM — Floating elements
   ------------------------------------------------------------------ */

.glass {
  background-color: var(--glass-bg);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
}

.glass-heavy {
  background-color: var(--glass-bg);
  backdrop-filter: blur(var(--glass-blur-heavy));
  -webkit-backdrop-filter: blur(var(--glass-blur-heavy));
}


/* ------------------------------------------------------------------
   LAYOUT
   ------------------------------------------------------------------ */

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

.container-narrow {
  max-width: var(--container-narrow);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.container-wide {
  max-width: var(--container-wide);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section {
  padding-block: var(--space-section);
}

.section-hero {
  padding-block: var(--space-section-hero);
}


/* ------------------------------------------------------------------
   GRID
   ------------------------------------------------------------------ */

.grid {
  display: grid;
  gap: var(--gutter);
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
  .grid-2,
  .grid-3,
  .grid-4 { grid-template-columns: 1fr; }
}


/* ------------------------------------------------------------------
   FLEX HELPERS
   ------------------------------------------------------------------ */

.flex         { display: flex; }
.flex-col     { flex-direction: column; }
.flex-wrap    { flex-wrap: wrap; }
.items-center { align-items: center; }
.items-start  { align-items: flex-start; }
.items-end    { align-items: flex-end; }
.justify-between { justify-content: space-between; }
.justify-center  { justify-content: center; }
.gap-2  { gap: var(--space-2); }
.gap-3  { gap: var(--space-3); }
.gap-4  { gap: var(--space-4); }
.gap-6  { gap: var(--space-6); }
.gap-8  { gap: var(--space-8); }


/* ------------------------------------------------------------------
   RADIUS — "Organic" vibe, no sharp corners
   ------------------------------------------------------------------ */

.rounded-sm   { border-radius: var(--radius-sm); }
.rounded-md   { border-radius: var(--radius-md); }
.rounded-lg   { border-radius: var(--radius-lg); }
.rounded-xl   { border-radius: var(--radius-xl); }
.rounded-full { border-radius: var(--radius-full); }


/* ------------------------------------------------------------------
   ELEVATION
   ------------------------------------------------------------------ */

.shadow-ambient { box-shadow: var(--shadow-ambient); }
.shadow-low     { box-shadow: var(--shadow-low); }
.shadow-medium  { box-shadow: var(--shadow-medium); }
.ghost-border   { outline: var(--ghost-border); }


/* ------------------------------------------------------------------
   BUTTONS — Per design system spec
   ------------------------------------------------------------------ */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-md);
  font-family: var(--font-body);
  font-size: var(--text-body-md);
  font-weight: 600;
  line-height: 1;
  text-decoration: none;
  cursor: pointer;
  transition:
    background-color var(--duration-normal) var(--ease-default),
    color var(--duration-normal) var(--ease-default),
    transform var(--duration-fast) var(--ease-default);
  white-space: nowrap;
}

.btn:active {
  transform: scale(0.98);
}

/* Primary — gradient from primary to primary-container */
.btn-primary {
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-container));
  color: var(--color-on-primary);
}

.btn-primary:hover {
  background: linear-gradient(135deg, var(--color-primary-container), var(--color-primary));
}

/* Secondary — surface-container-highest, no border */
.btn-secondary {
  background-color: var(--color-surface-container-highest);
  color: var(--color-primary);
}

.btn-secondary:hover {
  background-color: var(--color-surface-container-high);
}

/* Tertiary — text only, underline on hover */
.btn-tertiary {
  background: none;
  color: var(--color-primary);
  padding-inline: 0;
  position: relative;
}

.btn-tertiary::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 100%;
  height: 1px;
  background-color: var(--color-primary);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform var(--duration-normal) var(--ease-default);
}

.btn-tertiary:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}


/* ------------------------------------------------------------------
   HERB CHIP — Signature component for ingredient tags
   ------------------------------------------------------------------ */

.herb-chip {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-1) var(--space-3);
  background-color: var(--color-secondary-container);
  color: var(--color-on-secondary-container);
  border-radius: var(--radius-full);
  font-family: var(--font-body);
  font-size: var(--text-label-md);
  line-height: var(--text-label-md-lh);
  letter-spacing: var(--text-label-md-tracking);
  font-weight: var(--text-label-md-weight);
  text-transform: uppercase;
  white-space: nowrap;
}


/* ------------------------------------------------------------------
   INPUT FIELDS — Minimalist, bottom-border only
   ------------------------------------------------------------------ */

.input-field {
  position: relative;
}

.input-field input,
.input-field textarea,
.input-field select {
  width: 100%;
  padding: var(--space-3) 0;
  background: transparent;
  border: none;
  border-bottom: 1px solid rgba(118, 120, 107, 0.3); /* outline @ 30% */
  font-family: var(--font-body);
  font-size: var(--text-body-lg);
  color: var(--color-on-surface);
  transition: border-color var(--duration-normal) var(--ease-default);
  outline: none;
}

.input-field input:focus,
.input-field textarea:focus,
.input-field select:focus {
  border-bottom-color: var(--color-primary);
}

.input-field label {
  position: absolute;
  top: var(--space-3);
  left: 0;
  font-size: var(--text-body-lg);
  color: var(--color-on-surface-variant);
  pointer-events: none;
  transition:
    top var(--duration-normal) var(--ease-default),
    font-size var(--duration-normal) var(--ease-default);
}

.input-field input:focus ~ label,
.input-field input:not(:placeholder-shown) ~ label,
.input-field textarea:focus ~ label,
.input-field textarea:not(:placeholder-shown) ~ label {
  top: calc(-1 * var(--space-4));
  font-size: var(--text-label-sm);
  letter-spacing: var(--text-label-sm-tracking);
  color: var(--color-primary);
}


/* ------------------------------------------------------------------
   PAPER GRAIN — Subtle artisanal texture overlay
   Applied to body or section backgrounds
   ------------------------------------------------------------------ */

.grain::after {
  content: '';
  position: fixed;
  inset: 0;
  opacity: 0.025;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");
  pointer-events: none;
  z-index: 9999;
}


/* ------------------------------------------------------------------
   VISUALLY HIDDEN — Accessibility
   ------------------------------------------------------------------ */

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