/**
 * Shared Components - Reusable UI Components
 * Theme-agnostic components using CSS variables
 */

/* ============================================
   BUTTONS
   ============================================ */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-md) var(--space-lg);
  font-size: var(--text-base);
  font-weight: var(--font-semibold);
  line-height: var(--leading-none);
  text-align: center;
  text-decoration: none;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-base);
  min-height: var(--touch-target-min);
  white-space: nowrap;
  user-select: none;
}

.btn:focus-visible {
  outline: var(--focus-ring-width) solid currentColor;
  outline-offset: var(--focus-ring-offset);
}

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

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

/* Button Variants */
.btn-primary {
  background-color: var(--primary-color);
  color: var(--white);
}

.btn-primary:hover:not(:disabled) {
  background-color: var(--primary-dark, var(--primary-color));
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background-color: var(--secondary-color, var(--gray-200));
  color: var(--text-color, var(--gray-900));
}

.btn-secondary:hover:not(:disabled) {
  background-color: var(--secondary-dark, var(--gray-300));
}

.btn-ghost {
  background-color: transparent;
  color: var(--text-sub, var(--gray-600));
  font-weight: var(--font-medium);
}

.btn-ghost:hover:not(:disabled) {
  background-color: var(--gray-100);
  color: var(--text-color, var(--gray-900));
}

.btn-danger {
  background-color: var(--error-600);
  color: var(--white);
}

.btn-danger:hover:not(:disabled) {
  background-color: var(--error-700);
}

/* Button Sizes */
.btn-sm {
  padding: var(--space-sm) var(--space-md);
  font-size: var(--text-sm);
  min-height: 36px;
}

.btn-lg {
  padding: var(--space-lg) var(--space-xl);
  font-size: var(--text-lg);
  min-height: 52px;
}

/* Button States */
.btn.is-loading {
  position: relative;
  color: transparent;
  pointer-events: none;
}

.btn.is-loading::after {
  content: '';
  position: absolute;
  width: 16px;
  height: 16px;
  top: 50%;
  left: 50%;
  margin-left: -8px;
  margin-top: -8px;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top-color: white;
  animation: spin 0.6s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ============================================
   FORMS
   ============================================ */

.form-group {
  margin-bottom: var(--space-lg);
}

.form-label {
  display: block;
  font-size: var(--text-sm);
  font-weight: var(--font-semibold);
  margin-bottom: var(--space-sm);
  color: var(--text-color, var(--gray-700));
}

.form-label.required::after {
  content: ' *';
  color: var(--error-600);
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: var(--space-md);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--text-color, var(--gray-900));
  background-color: var(--input-bg, var(--white));
  border: 1px solid var(--border-color, var(--gray-300));
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
  min-height: var(--touch-target-min);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px var(--primary-light, rgba(59, 130, 246, 0.1));
}

.form-input::placeholder {
  color: var(--gray-400);
}

.form-textarea {
  min-height: 100px;
  resize: vertical;
}

/* Form States */
.form-input.is-valid,
.form-select.is-valid,
.form-textarea.is-valid {
  border-color: var(--success-600);
  background-color: var(--success-50);
}

.form-input.is-invalid,
.form-select.is-invalid,
.form-textarea.is-invalid {
  border-color: var(--error-600);
  background-color: var(--error-50);
  animation: shake 0.4s ease;
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  10%, 30%, 50%, 70%, 90% { transform: translateX(-4px); }
  20%, 40%, 60%, 80% { transform: translateX(4px); }
}

.form-input.is-verified {
  border-color: var(--success-600);
  background-color: var(--success-50);
  color: var(--success-700);
  padding-right: 48px;
}

.form-input[readonly] {
  background-color: var(--gray-50);
  cursor: not-allowed;
}

/* Helper text */
.form-helper {
  display: block;
  margin-top: var(--space-xs);
  font-size: var(--text-sm);
  color: var(--gray-600);
}

.form-error {
  display: block;
  margin-top: var(--space-xs);
  font-size: var(--text-sm);
  color: var(--error-600);
  font-weight: var(--font-medium);
}

/* Verified Icon */
.verified-icon {
  position: absolute;
  right: 12px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--success-600);
  font-size: var(--text-xl);
  font-weight: var(--font-bold);
  pointer-events: none;
  animation: checkmark 0.4s cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

@keyframes checkmark {
  0% {
    transform: translateY(-50%) scale(0);
    opacity: 0;
  }
  50% {
    transform: translateY(-50%) scale(1.2);
  }
  100% {
    transform: translateY(-50%) scale(1);
    opacity: 1;
  }
}

/* ============================================
   CARDS
   ============================================ */

.card {
  background-color: var(--card-bg, var(--white));
  border: 1px solid var(--border-color, var(--gray-200));
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-base);
}

.card:hover {
  box-shadow: var(--shadow-md);
}

.card-header {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-bottom: var(--space-md);
  padding-bottom: var(--space-md);
  border-bottom: 1px solid var(--border-color, var(--gray-200));
}

.card-title {
  font-size: var(--text-lg);
  font-weight: var(--font-bold);
  color: var(--heading-color, var(--gray-900));
  margin: 0;
}

.card-body {
  line-height: var(--leading-relaxed);
}

.card-footer {
  margin-top: var(--space-lg);
  padding-top: var(--space-lg);
  border-top: 1px solid var(--border-color, var(--gray-200));
}

/* ============================================
   BADGES
   ============================================ */

.badge {
  display: inline-flex;
  align-items: center;
  padding: var(--space-xs) var(--space-sm);
  font-size: var(--text-xs);
  font-weight: var(--font-semibold);
  line-height: var(--leading-none);
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: var(--tracking-wide);
}

.badge-success {
  background-color: var(--success-100);
  color: var(--success-700);
}

.badge-error {
  background-color: var(--error-100);
  color: var(--error-700);
}

.badge-warning {
  background-color: var(--warning-100);
  color: var(--warning-700);
}

.badge-info {
  background-color: var(--info-100);
  color: var(--info-700);
}

/* ============================================
   ALERTS / BANNERS
   ============================================ */

.alert {
  display: flex;
  align-items: flex-start;
  gap: var(--space-md);
  padding: var(--space-md);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  line-height: var(--leading-relaxed);
  margin-bottom: var(--space-md);
  animation: slideDown 0.5s ease;
}

@keyframes slideDown {
  from {
    transform: translateY(-100%);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

.alert svg {
  flex-shrink: 0;
  width: 20px;
  height: 20px;
}

.alert-success {
  background-color: var(--success-50);
  border: 1px solid var(--success-200, var(--success-100));
  color: var(--success-700);
}

.alert-error {
  background-color: var(--error-50);
  border: 1px solid var(--error-200, var(--error-100));
  color: var(--error-700);
}

.alert-warning {
  background-color: var(--warning-50);
  border: 1px solid var(--warning-200, var(--warning-100));
  color: var(--warning-700);
}

.alert-info {
  background-color: var(--info-50);
  border: 1px solid var(--info-200, var(--info-100));
  color: var(--info-700);
}

/* ============================================
   DIVIDER
   ============================================ */

.divider {
  display: flex;
  align-items: center;
  text-align: center;
  margin: var(--space-lg) 0;
  color: var(--gray-600);
  font-size: var(--text-sm);
  text-transform: uppercase;
  letter-spacing: var(--tracking-wide);
}

.divider::before,
.divider::after {
  content: '';
  flex: 1;
  border-bottom: 1px solid var(--border-color, var(--gray-300));
}

.divider span {
  padding: 0 var(--space-md);
}

/* ============================================
   LOADING STATES
   ============================================ */

.spinner {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 2px solid rgba(0, 0, 0, 0.1);
  border-top-color: currentColor;
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

.spinner-lg {
  width: 48px;
  height: 48px;
  border-width: 4px;
}

/* Skeleton Loading */
.skeleton {
  background: linear-gradient(
    90deg,
    var(--gray-200) 25%,
    var(--gray-100) 50%,
    var(--gray-200) 75%
  );
  background-size: 200% 100%;
  animation: shimmer 1.5s infinite;
  border-radius: var(--radius-sm);
}

@keyframes shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

.skeleton-text {
  height: 16px;
  margin-bottom: var(--space-sm);
}

.skeleton-text.short {
  width: 60%;
}

.skeleton-heading {
  height: 24px;
  width: 80%;
  margin-bottom: var(--space-md);
}

/* ============================================
   MODAL OVERLAY
   ============================================ */

.overlay {
  position: fixed;
  inset: 0;
  background-color: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: var(--z-modal-backdrop);
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.overlay.hidden {
  display: none;
}

/* ============================================
   FILE UPLOAD
   ============================================ */

.file-upload {
  border: 2px dashed var(--border-color, var(--gray-300));
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  text-align: center;
  cursor: pointer;
  transition: all var(--transition-base);
}

.file-upload:hover,
.file-upload.drag-over {
  border-color: var(--primary-color);
  background-color: var(--primary-light, rgba(59, 130, 246, 0.05));
}

.file-upload-icon {
  font-size: 48px;
  margin-bottom: var(--space-sm);
  opacity: 0.5;
}

.file-upload-text {
  font-size: var(--text-base);
  font-weight: var(--font-medium);
  margin-bottom: var(--space-xs);
}

.file-upload-sub {
  font-size: var(--text-sm);
  color: var(--gray-600);
}

/* ============================================
   PROGRESS BAR
   ============================================ */

.progress {
  width: 100%;
  height: 8px;
  background-color: var(--gray-200);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.progress-bar {
  height: 100%;
  background-color: var(--primary-color);
  border-radius: var(--radius-full);
  transition: width var(--transition-base);
}

/* ============================================
   BACK BUTTON
   ============================================ */

.back-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  min-height: var(--touch-target-min);
  min-width: var(--touch-target-min);
  border-radius: var(--radius-full);
  transition: background-color var(--transition-fast);
  cursor: pointer;
}

.back-btn:hover {
  background-color: rgba(255, 255, 255, 0.2);
}

.back-btn svg {
  width: 24px;
  height: 24px;
}