/* ============================================================================
 * Button system
 *   .wb-btn                     → base
 *   .wb-btn--primary | --secondary | --ghost | --link | --ink
 *   .wb-btn--sm | --md (default) | --lg
 *   .wb-btn--block              → full width
 *   .wb-btn--icon               → square icon button
 * ========================================================================== */

.wb-btn {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--wb-space-2);
  padding: 0.75rem 1.375rem;
  font-family: var(--wb-font-sans);
  font-size: var(--wb-text-sm);
  font-weight: var(--wb-fw-semibold);
  line-height: 1;
  letter-spacing: -0.005em;
  color: var(--wb-color-ink);
  background-color: transparent;
  border: var(--wb-border-width) solid transparent;
  border-radius: var(--wb-radius-md);
  cursor: pointer;
  user-select: none;
  text-decoration: none;
  white-space: nowrap;
  overflow: hidden;
  transition:
    background-color var(--wb-duration-base) var(--wb-ease),
    border-color var(--wb-duration-base) var(--wb-ease),
    color var(--wb-duration-base) var(--wb-ease),
    transform var(--wb-duration-fast) var(--wb-ease),
    box-shadow var(--wb-duration-base) var(--wb-ease);
}

.wb-btn:focus-visible {
  outline: var(--wb-focus-width) solid var(--wb-color-focus-ring);
  outline-offset: 2px;
}

.wb-btn[disabled],
.wb-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
}

/* Primary — solid brand with subtle inner highlight and hover state */
.wb-btn--primary {
  background-image: linear-gradient(180deg, #333333 0%, var(--wb-color-brand) 100%);
  background-color: var(--wb-color-brand);
  color: var(--wb-color-white);
  border-color: var(--wb-color-brand);
  box-shadow:
    0 1px 0 rgba(255, 255, 255, 0.15) inset,
    0 4px 12px rgba(17, 17, 17, 0.12);
}
.wb-btn--primary:hover {
  background-image: linear-gradient(180deg, #444444 0%, #000000 100%);
  color: var(--wb-color-white);
  box-shadow:
    0 1px 0 rgba(255, 255, 255, 0.2) inset,
    0 6px 16px rgba(17, 17, 17, 0.18);
  transform: translateY(-1px);
}
.wb-btn--primary:active:not(:disabled) { transform: translateY(0); }

/* Secondary — refined outline that is visible on light/white backgrounds */
.wb-btn--secondary {
  background-color: var(--wb-color-bg-soft);
  color: var(--wb-color-ink);
  border-color: var(--wb-color-border);
  box-shadow: 0 1px 1px rgba(0, 0, 0, 0.02);
}
.wb-btn--secondary:hover {
  background-color: var(--wb-color-bg-muted);
  border-color: var(--wb-color-border-strong);
  color: var(--wb-color-ink);
  transform: translateY(-1px);
}

.wb-btn--ghost {
  background-color: transparent;
  color: var(--wb-color-ink);
  border-color: transparent;
}
.wb-btn--ghost:hover {
  background-color: var(--wb-color-bg-muted);
}

.wb-btn--link {
  padding: 0;
  background: transparent;
  border: 0;
  color: var(--wb-color-brand);
  border-radius: 0;
}
.wb-btn--link:hover {
  color: var(--wb-color-brand-hover);
  text-decoration: underline;
  text-underline-offset: 4px;
}

.wb-btn--ink {
  background-color: var(--wb-color-ink);
  color: var(--wb-color-white);
  border-color: var(--wb-color-ink);
}
.wb-btn--ink:hover {
  background-color: var(--wb-color-ink-2);
  border-color: var(--wb-color-ink-2);
  color: var(--wb-color-white);
}

/* Sizes */
.wb-btn--sm {
  padding: 0.5rem 1rem;
  font-size: var(--wb-text-xs);
  border-radius: var(--wb-radius-sm);
}

.wb-btn--lg {
  padding: 1rem 1.75rem;
  font-size: var(--wb-text-base);
  border-radius: var(--wb-radius-lg);
}

.wb-btn--block {
  display: flex;
  width: 100%;
}

.wb-btn--icon {
  padding: 0.625rem;
  aspect-ratio: 1 / 1;
}

/* Subtle press feedback (kept understated, no bounce) */
.wb-btn:active:not(:disabled) {
  transform: translateY(1px);
}

/* Icon slots inside buttons — accept svg or <i> */
.wb-btn__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1em;
  height: 1em;
  flex-shrink: 0;
  line-height: 1;
}
.wb-btn__icon svg { width: 100%; height: 100%; display: block; }

.wb-btn--with-icon-trail .wb-btn__icon { transition: transform var(--wb-duration-base) var(--wb-ease); }
.wb-btn--with-icon-trail:hover .wb-btn__icon { transform: translateX(2px); }

/* Loading state — spinner overlay, content hidden but space preserved */
.wb-btn--loading {
  position: relative;
  color: transparent !important;
  pointer-events: none;
}
.wb-btn--loading::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 1em;
  height: 1em;
  margin: -0.5em 0 0 -0.5em;
  border-radius: 50%;
  border: 1.75px solid currentColor;
  border-right-color: transparent;
  color: var(--wb-color-white);
  animation: wb-btn-spin 0.65s linear infinite;
}
.wb-btn--secondary.wb-btn--loading::after,
.wb-btn--ghost.wb-btn--loading::after { color: var(--wb-color-ink); }

@keyframes wb-btn-spin {
  to { transform: rotate(360deg); }
}
.wb-reduce-motion .wb-btn--loading::after { animation-duration: 1.5s; }

/* Button group — adjacent buttons sit flush with no extra wrapping */
.wb-btn-group {
  display: inline-flex;
  flex-wrap: wrap;
  gap: var(--wb-space-3);
}
.wb-btn-group--tight { gap: var(--wb-space-2); }
.wb-btn-group--block { display: flex; width: 100%; }
.wb-btn-group--block .wb-btn { flex: 1 1 0; }