/* ============================================================
   Component: BUTTONS
   Variants: primary, success, danger, warning, neutral,
             outline, ghost, soft, surface
   Sizes: xs, sm, default, lg
   Mods: high-contrast, radius-full, radius-none, loading, block
   Theme-ready: uses --color-link, --color-bg, etc.
   ============================================================ */

/* ── Base button reset ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  font-family: inherit;
  font-size: 0.88rem;
  font-weight: 600;
  line-height: 1;           /* tight: height = padding×2 + font-size */
  padding: 10px 20px;
  border-radius: var(--border-radius);
  border: 2px solid transparent;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, color 0.15s, box-shadow 0.15s, transform 0.1s;
  text-decoration: none;
  white-space: nowrap;
  user-select: none;
  vertical-align: middle;
}
.btn:active { transform: scale(0.97); }
.btn:disabled,
.btn--disabled {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
}

/* ── Solid variants ── */

/* Primary (link color) */
.btn--primary {
  background: var(--color-link);
  border-color: var(--color-link);
  color: var(--color-button-text, #fff);
}
.btn--primary:hover { filter: brightness(1.1); }

/* Success (green) */
.btn--success {
  background: var(--color-success);
  border-color: var(--color-success);
  color: #fff;
}
.btn--success:hover { background: var(--color-success-hover); border-color: var(--color-success-hover); }

/* Danger (red) */
.btn--danger {
  background: var(--color-danger);
  border-color: var(--color-danger);
  color: #fff;
}
.btn--danger:hover { background: var(--color-danger-hover); border-color: var(--color-danger-hover); }

/* Warning (amber) */
.btn--warning {
  background: var(--color-warning);
  border-color: var(--color-warning);
  color: #fff;
}
.btn--warning:hover { background: var(--color-warning-hover); border-color: var(--color-warning-hover); }

/* Neutral (grey, theme-aware) */
.btn--neutral {
  background: var(--color-bg-secondary);
  border-color: var(--color-bg-secondary);
  color: var(--color-text);
}
.btn--neutral:hover { filter: brightness(0.95); }

/* ── Subtle variants ── */

/* Outline */
.btn--outline {
  background: transparent;
  border-color: var(--color-link);
  color: var(--color-link);
}
.btn--outline:hover { background: var(--color-link); color: var(--color-button-text, #fff); }

/* Ghost */
.btn--ghost {
  background: transparent;
  border-color: transparent;
  color: var(--color-text);
}
.btn--ghost:hover { background: var(--color-bg-secondary); }

/* Soft — subtle tint, no border, inherits link hue */
.btn--soft {
  background: color-mix(in srgb, var(--color-link) 12%, transparent);
  border-color: transparent;
  color: var(--color-link);
}
.btn--soft:hover { background: color-mix(in srgb, var(--color-link) 20%, transparent); }

/* Surface — card-like, raised */
.btn--surface {
  background: var(--color-bg);
  border-color: var(--color-bg-secondary);
  color: var(--color-text);
  box-shadow: 0 1px 3px color-mix(in srgb, var(--color-text-secondary) 12%, transparent);
}
.btn--surface:hover { background: var(--color-bg-secondary); border-color: color-mix(in srgb, var(--color-text-secondary) 30%, transparent); }

/* ── High Contrast Modifier ── */
.btn--high-contrast.btn--outline,
.btn--high-contrast.btn--ghost,
.btn--high-contrast.btn--soft,
.btn--high-contrast.btn--surface {
  background: var(--color-link);
  border-color: var(--color-link);
  color: var(--color-button-text, #fff);
}
.btn--high-contrast.btn--outline:hover,
.btn--high-contrast.btn--ghost:hover,
.btn--high-contrast.btn--soft:hover,
.btn--high-contrast.btn--surface:hover { filter: brightness(1.1); }

/* ── Sizes ── */

.btn--xs {
  font-size: 0.7rem;
  padding: 4px 10px;
  border-radius: calc(var(--border-radius) * 0.6);
  gap: 4px;
}

.btn--sm {
  font-size: 0.78rem;
  padding: 6px 14px;
  border-radius: calc(var(--border-radius) * 0.75);
  gap: 5px;
}

.btn--lg {
  font-size: 1rem;
  padding: 13px 26px;
  border-radius: calc(var(--border-radius) * 1.25);
  gap: 8px;
}

/* ── Icon-only button ── */
.btn--icon {
  width: 40px;
  height: 40px;
  padding: 0;
  border-radius: 50%;
}
.btn--icon.btn--xs { width: 26px; height: 26px; }
.btn--icon.btn--sm { width: 32px; height: 32px; }
.btn--icon.btn--lg { width: 50px; height: 50px; }

/* ── Block (full width) ── */
.btn--block { display: flex; width: 100%; }

/* ── Radius variants ── */
.btn--radius-full { border-radius: 9999px; }
.btn--radius-none  { border-radius: 0; }

/* ── Loading state ── */
.btn--loading {
  position: relative;
  color: transparent !important;
  pointer-events: none;
}
.btn--loading::after {
  content: '';
  position: absolute;
  inset: 0;
  margin: auto;
  width: 18px; height: 18px;
  border: 2px solid rgba(255,255,255,0.3);
  border-top-color: #fff;
  border-radius: 50%;
  animation: btn-spin 0.6s linear infinite;
}
/* Spinner color for light-background variants */
.btn--loading.btn--outline::after,
.btn--loading.btn--ghost::after,
.btn--loading.btn--soft::after,
.btn--loading.btn--surface::after,
.btn--loading.btn--neutral::after {
  border-color: color-mix(in srgb, var(--color-link) 25%, transparent);
  border-top-color: var(--color-link);
}
@keyframes btn-spin { to { transform: rotate(360deg); } }