/* Base Button Styles */
.button {
  /* Layout */
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  
  /* Typography */
  font-family: inherit;
  font-weight: 500;
  text-decoration: none;
  white-space: nowrap;
  
  /* Interaction */
  cursor: pointer;
  transition: all 0.2s ease;
  border: 1px solid transparent;
  
  /* Appearance */
  border-radius: 0.375rem;
  outline: none;
}

.button:focus-visible {
  outline: 2px solid var(--focus-ring);
  outline-offset: var(--focus-ring-offset);
}

.button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  pointer-events: none;
}

/* Size Variants */
.button-small {
  padding: 0.375rem 0.75rem;
  font-size: 0.75rem;
  border-radius: 0.25rem;
}

.button-medium {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

.button-large {
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  font-weight: 600;
}

/* Primary Variant */
.button-primary {
  background: var(--btn-primary-bg);
  color: var(--btn-primary-text);
  border-color: var(--btn-primary-border);
}

.button-primary:hover:not(:disabled) {
  background: var(--btn-primary-bg-hover);
  border-color: var(--btn-primary-border-hover);
}

.button-primary:active:not(:disabled) {
  background: var(--btn-primary-bg-active);
  border-color: var(--btn-primary-bg-active);
}

/* Secondary Variant */
.button-secondary {
  background: var(--btn-secondary-bg);
  color: var(--btn-secondary-text);
  border-color: var(--btn-secondary-border);
}

.button-secondary:hover:not(:disabled) {
  background: var(--btn-secondary-bg-hover);
  color: var(--btn-secondary-text-hover);
  border-color: var(--btn-secondary-border-hover);
}

.button-secondary:active:not(:disabled) {
  background: var(--btn-secondary-bg-active);
  color: var(--btn-secondary-text-active);
}

/* Danger Variant */
.button-danger {
  background: var(--btn-danger-bg);
  color: var(--btn-danger-text);
  border-color: var(--btn-danger-border);
}

.button-danger:hover:not(:disabled) {
  background: var(--btn-danger-bg-hover);
  border-color: var(--btn-danger-border-hover);
}

.button-danger:active:not(:disabled) {
  background: var(--btn-danger-bg-active);
  border-color: var(--btn-danger-bg-active);
}

/* Link Variant */
.button-link {
  background: none;
  color: var(--text-secondary);
  border: none;
  text-decoration: underline;
  padding: 0.25rem 0.5rem;
}

.button-link:hover:not(:disabled) {
  color: var(--text-primary);
}

.button-link:active:not(:disabled) {
  color: var(--text-primary);
}

/* Loading State */
.button-loading {
  position: relative;
  color: transparent;
}

.button-loading::after {
  content: '';
  position: absolute;
  width: 1rem;
  height: 1rem;
  border: 2px solid transparent;
  border-top: 2px solid currentColor;
  border-radius: 50%;
  animation: button-spin 1s linear infinite;
  color: inherit;
}

@keyframes button-spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}