/**
 * Commerce Learning Hub - Extended Form Components
 * 
 * Input groups, validation states, custom controls, range sliders.
 */

/* ============================================
   INPUT GROUPS (with prefix/suffix)
   ============================================ */
.input-group {
  display: flex;
  align-items: stretch;
  width: 100%;
}

.input-group__prefix,
.input-group__suffix {
  display: flex;
  align-items: center;
  padding: 0 var(--space-3);
  background: var(--color-surface-elevated);
  border: 1px solid var(--color-border);
  color: var(--color-text-secondary);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  white-space: nowrap;
}

.input-group__prefix {
  border-right: none;
  border-radius: var(--radius-md) 0 0 var(--radius-md);
}

.input-group__suffix {
  border-left: none;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

.input-group .form-input {
  flex: 1;
  min-width: 0;
}

.input-group .form-input:not(:first-child):not(:last-child) {
  border-radius: 0;
}

.input-group .form-input:first-child {
  border-radius: var(--radius-md) 0 0 var(--radius-md);
}

.input-group .form-input:last-child {
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

/* ============================================
   VALIDATION STATES
   ============================================ */
.form-group--success .form-input,
.form-group--success .form-select,
.form-group--success .form-textarea {
  border-color: var(--color-success);
}

.form-group--success .form-input:focus,
.form-group--success .form-select:focus {
  box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.15);
}

.form-group--error .form-input,
.form-group--error .form-select,
.form-group--error .form-textarea {
  border-color: var(--color-error);
}

.form-group--error .form-input:focus,
.form-group--error .form-select:focus {
  box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.15);
}

.form-group--warning .form-input,
.form-group--warning .form-select,
.form-group--warning .form-textarea {
  border-color: var(--color-warning);
}

.form-group--warning .form-input:focus {
  box-shadow: 0 0 0 3px rgba(245, 158, 11, 0.15);
}

.form-validation-icon {
  position: absolute;
  right: 0.75rem;
  top: 50%;
  transform: translateY(-50%);
  font-size: var(--text-base);
}

.form-group--success .form-validation-icon::before { content: '✓'; color: var(--color-success); }
.form-group--error .form-validation-icon::before { content: '✕'; color: var(--color-error); }
.form-group--warning .form-validation-icon::before { content: '⚠'; color: var(--color-warning); }

.form-input-wrapper {
  position: relative;
}

/* ============================================
   RANGE SLIDER
   ============================================ */
.range-slider {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 6px;
  background: var(--color-border);
  border-radius: var(--radius-full);
  outline: none;
  transition: background var(--transition-fast);
}

.range-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 20px;
  height: 20px;
  background: var(--color-primary);
  border-radius: 50%;
  cursor: pointer;
  border: 3px solid var(--color-surface);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-fast);
}

.range-slider::-webkit-slider-thumb:hover {
  transform: scale(1.15);
  background: var(--color-primary-hover);
}

.range-slider::-moz-range-thumb {
  width: 20px;
  height: 20px;
  background: var(--color-primary);
  border-radius: 50%;
  cursor: pointer;
  border: 3px solid var(--color-surface);
  box-shadow: var(--shadow-md);
}

.range-slider:focus-visible {
  outline: none;
}

.range-slider:focus-visible::-webkit-slider-thumb {
  box-shadow: 0 0 0 3px var(--color-primary-light);
}

.range-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.range-group__header {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.range-group__value {
  font-weight: var(--font-semibold);
  color: var(--color-primary);
  font-size: var(--text-sm);
  min-width: 4rem;
  text-align: right;
}

.range-group__ticks {
  display: flex;
  justify-content: space-between;
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  margin-top: var(--space-1);
}

/* ============================================
   TOGGLE SWITCH
   ============================================ */
.toggle {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  cursor: pointer;
  user-select: none;
}

.toggle__input {
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
}

.toggle__slider {
  position: relative;
  width: 44px;
  height: 24px;
  background: var(--color-border-strong);
  border-radius: var(--radius-full);
  transition: background var(--transition-fast);
  flex-shrink: 0;
}

.toggle__slider::before {
  content: '';
  position: absolute;
  top: 2px;
  left: 2px;
  width: 20px;
  height: 20px;
  background: white;
  border-radius: 50%;
  transition: transform var(--transition-fast);
  box-shadow: var(--shadow-sm);
}

.toggle__input:checked + .toggle__slider {
  background: var(--color-primary);
}

.toggle__input:checked + .toggle__slider::before {
  transform: translateX(20px);
}

.toggle__input:focus-visible + .toggle__slider {
  box-shadow: 0 0 0 3px var(--color-primary-light);
}

.toggle__label {
  font-size: var(--text-sm);
  color: var(--color-text);
  font-weight: var(--font-medium);
}

/* ============================================
   CUSTOM CHECKBOX & RADIO
   ============================================ */
.checkbox,
.radio {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  cursor: pointer;
  user-select: none;
  font-size: var(--text-sm);
  color: var(--color-text);
}

.checkbox__input,
.radio__input {
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
}

.checkbox__box,
.radio__box {
  width: 18px;
  height: 18px;
  border: 2px solid var(--color-border-strong);
  background: var(--color-surface);
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.checkbox__box {
  border-radius: var(--radius-sm);
}

.radio__box {
  border-radius: 50%;
}

.checkbox__input:checked + .checkbox__box {
  background: var(--color-primary);
  border-color: var(--color-primary);
}

.checkbox__input:checked + .checkbox__box::after {
  content: '✓';
  color: white;
  font-size: 12px;
  font-weight: bold;
}

.radio__input:checked + .radio__box {
  border-color: var(--color-primary);
  border-width: 6px;
}

.checkbox__input:focus-visible + .checkbox__box,
.radio__input:focus-visible + .radio__box {
  box-shadow: 0 0 0 3px var(--color-primary-light);
}

/* ============================================
   FILE UPLOAD
   ============================================ */
.file-upload {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--space-8);
  border: 2px dashed var(--color-border-strong);
  border-radius: var(--radius-lg);
  background: var(--color-surface);
  cursor: pointer;
  transition: all var(--transition-fast);
  text-align: center;
}

.file-upload:hover {
  border-color: var(--color-primary);
  background: var(--color-primary-light);
}

.file-upload__input {
  position: absolute;
  inset: 0;
  opacity: 0;
  cursor: pointer;
}

.file-upload__icon {
  font-size: var(--text-4xl);
  margin-bottom: var(--space-2);
}

.file-upload__text {
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
}

.file-upload__text strong {
  color: var(--color-primary);
}

/* ============================================
   SEARCH INPUT
   ============================================ */
.search-input {
  position: relative;
}

.search-input__icon {
  position: absolute;
  left: 0.875rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--color-text-muted);
  pointer-events: none;
}

.search-input__input {
  width: 100%;
  padding: var(--space-2) var(--space-3) var(--space-2) 2.5rem;
}

.search-input__clear {
  position: absolute;
  right: 0.5rem;
  top: 50%;
  transform: translateY(-50%);
  width: 1.5rem;
  height: 1.5rem;
  border-radius: 50%;
  background: var(--color-surface-elevated);
  display: none;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}

.search-input__clear--visible {
  display: flex;
}

/* ============================================
   FORM LAYOUT HELPERS
   ============================================ */
.form-row {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-4);
}

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

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

.form-actions {
  display: flex;
  gap: var(--space-3);
  margin-top: var(--space-6);
  flex-wrap: wrap;
}

.form-divider {
  height: 1px;
  background: var(--color-border);
  margin: var(--space-6) 0;
}

.form-section-title {
  font-size: var(--text-sm);
  font-weight: var(--font-semibold);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-muted);
  margin-bottom: var(--space-3);
}