/* ============================================
   REUSABLE COMPONENTS
   ============================================ */

/* ==================== BUTTONS ==================== */
.btn {
  padding: 10px var(--spacing-lg);
  border: none;
  border-radius: 999px;
  font-size: var(--font-size-sm);
  font-weight: 600;
  letter-spacing: 0.02em;
  cursor: pointer;
  transition: all var(--transition-fast);
  font-family: var(--font-family);
  display: inline-block;
  text-align: center;
  white-space: nowrap;
}

.btn:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn:active {
  transform: translateY(0);
  box-shadow: none;
}

.btn:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 3px;
}

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

/* Button Variants */
.btn-primary {
  background-color: var(--primary-color);
  color: var(--text-white);
  box-shadow: 0 1px 4px rgba(99, 102, 241, 0.3);
}

.btn-primary:hover {
  background-color: var(--primary-dark);
  box-shadow: 0 4px 14px rgba(99, 102, 241, 0.4);
}

.btn-secondary {
  background-color: var(--bg-hover);
  color: var(--text-primary);
  border: 2px solid var(--border-color);
}

.btn-secondary:hover {
  background-color: var(--border-color);
}

.btn-secondary.active {
  background-color: var(--primary-color);
  color: var(--text-white);
  border-color: var(--primary-color);
}

.btn-success {
  background-color: var(--secondary-color);
  color: var(--text-white);
  box-shadow: 0 1px 4px rgba(16, 185, 129, 0.3);
}

.btn-success:hover {
  background-color: var(--secondary-dark);
  box-shadow: 0 4px 14px rgba(16, 185, 129, 0.4);
}

.btn-danger {
  background-color: var(--accent-color);
  color: var(--text-white);
}

.btn-danger:hover {
  background-color: #e55555;
}

.btn-outline {
  background-color: transparent;
  color: var(--primary-color);
  border: 2px solid var(--primary-color);
}

.btn-outline:hover {
  background-color: var(--primary-color);
  color: var(--text-white);
}

/* Button Groups */
.btn-group {
  display: flex;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
  justify-content: center;
}

.btn-group .btn {
  flex: 1;
  min-width: 120px;
}

/* ==================== MODAL ==================== */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.6);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 3000;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-base);
  backdrop-filter: blur(4px);
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal-content {
  background: var(--bg-card);
  border-radius: var(--border-radius);
  padding: var(--spacing-xl);
  max-width: 600px;
  width: 90%;
  max-height: 80vh;
  overflow-y: auto;
  box-shadow: var(--shadow-lg);
  position: relative;
  transform: scale(0.9);
  transition: transform var(--transition-base);
}

.modal-overlay.active .modal-content {
  transform: scale(1);
}

.modal-close {
  position: absolute;
  top: var(--spacing-md);
  right: var(--spacing-md);
  background: transparent;
  border: none;
  font-size: 32px;
  line-height: 1;
  cursor: pointer;
  color: var(--text-light);
  transition: color var(--transition-fast);
  padding: 0;
  width: 32px;
  height: 32px;
}

.modal-close:hover {
  color: var(--text-primary);
}

#modal-body {
  padding-top: var(--spacing-md);
}

/* Modal Specific Content */
.modal-header {
  margin-bottom: var(--spacing-lg);
}

.modal-header h2 {
  color: var(--primary-color);
  margin-bottom: var(--spacing-sm);
}

.modal-actions {
  display: flex;
  gap: var(--spacing-md);
  justify-content: flex-end;
  margin-top: var(--spacing-lg);
}

/* ==================== PROGRESS BARS ==================== */
.progress-bar-container {
  margin-bottom: var(--spacing-lg);
}

.progress-bar-label {
  display: flex;
  justify-content: space-between;
  margin-bottom: var(--spacing-xs);
  font-weight: 600;
  color: var(--text-primary);
}

.progress-bar-track {
  width: 100%;
  height: 10px;
  background-color: var(--bg-hover);
  border-radius: 999px;
  overflow: hidden;
  position: relative;
}

.progress-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--primary-color), var(--primary-light));
  border-radius: 999px;
  transition: width var(--transition-slow);
  min-width: 4px;
}

.progress-bar-percentage {
  text-align: right;
  margin-top: 4px;
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
}

/* Progress Bar Variants */
.progress-bar-fill.success {
  background: linear-gradient(90deg, var(--secondary-color), #34d399);
}

.progress-bar-fill.warning {
  background: linear-gradient(90deg, #f59e0b, #fbbf24);
}

.progress-bar-fill.danger {
  background: linear-gradient(90deg, var(--accent-color), #fb7185);
}

/* ==================== CARDS ==================== */
.card {
  background: var(--bg-card);
  border-radius: var(--border-radius);
  padding: var(--spacing-lg);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-color);
  margin-bottom: var(--spacing-md);
}

.card-header {
  border-bottom: 1px solid var(--border-color);
  padding-bottom: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
}

.card-header h3 {
  margin: 0;
  color: var(--text-primary);
}

.card-body {
  color: var(--text-secondary);
}

.card-footer {
  border-top: 1px solid var(--border-color);
  padding-top: var(--spacing-md);
  margin-top: var(--spacing-md);
}

/* ==================== BADGES ==================== */
.badge {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.02em;
  line-height: 1.4;
}

.badge-primary {
  background-color: var(--primary-color);
  color: var(--text-white);
}

.badge-secondary {
  background-color: var(--text-light);
  color: var(--text-white);
}

.badge-success {
  background-color: var(--secondary-color);
  color: var(--text-white);
}

.badge-custom {
  background-color: #e8610a;
  color: #fff;
}

.btn-text-danger {
  background: none;
  border: 1px solid var(--accent-color);
  border-radius: 999px;
  padding: 3px 12px;
  font-size: 0.75rem;
  color: var(--accent-color);
  cursor: pointer;
  opacity: 0.7;
}

.btn-text-danger:hover {
  opacity: 1;
  background-color: rgba(var(--accent-rgb, 220, 80, 80), 0.08);
}

.badge-danger {
  background-color: var(--accent-color);
  color: var(--text-white);
}

/* ==================== FORMS ==================== */
.form-group {
  margin-bottom: var(--spacing-md);
}

.form-label {
  display: block;
  margin-bottom: var(--spacing-xs);
  font-weight: 600;
  color: var(--text-primary);
}

.form-input,
.form-textarea,
.form-select {
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-md);
  border: 1.5px solid var(--border-color);
  border-radius: var(--border-radius-sm);
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  background-color: var(--bg-card);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.12);
}

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

.form-help {
  display: block;
  margin-top: 4px;
  font-size: var(--font-size-sm);
  color: var(--text-light);
}

/* ==================== ALERTS ==================== */
.alert {
  padding: var(--spacing-md);
  border-radius: var(--border-radius-sm);
  margin-bottom: var(--spacing-md);
  border-left: 4px solid;
}

.alert-info {
  background-color: #eef2ff;
  border-color: var(--primary-color);
  color: #3730a3;
}

.alert-success {
  background-color: #ecfdf5;
  border-color: var(--secondary-color);
  color: #065f46;
}

.alert-warning {
  background-color: #fffbeb;
  border-color: #f59e0b;
  color: #92400e;
}

.alert-danger {
  background-color: #fff1f2;
  border-color: var(--accent-color);
  color: #9f1239;
}

/* ==================== LOADING SPINNER ==================== */
.spinner {
  width: 40px;
  height: 40px;
  border: 4px solid var(--border-color);
  border-top-color: var(--primary-color);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  margin: var(--spacing-lg) auto;
}

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

.spinner-small {
  width: 20px;
  height: 20px;
  border-width: 2px;
}

.loading-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-xl);
}

.loading-text {
  margin-top: var(--spacing-md);
  color: var(--text-secondary);
}

/* ==================== DIVIDER ==================== */
.divider {
  height: 1px;
  background-color: var(--border-color);
  margin: var(--spacing-lg) 0;
}

.divider-text {
  text-align: center;
  position: relative;
  margin: var(--spacing-lg) 0;
}

.divider-text:before {
  content: "";
  position: absolute;
  top: 50%;
  left: 0;
  right: 0;
  height: 1px;
  background-color: var(--border-color);
}

.divider-text span {
  background-color: var(--bg-main);
  padding: 0 var(--spacing-md);
  position: relative;
  color: var(--text-secondary);
  font-size: var(--font-size-sm);
}

/* ==================== EXERCISE COMPONENTS ==================== */
.exercise-question {
  background: var(--bg-hover);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-sm);
  margin-bottom: var(--spacing-md);
  font-size: var(--font-size-lg);
  line-height: 1.8;
}

.exercise-options {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  margin: var(--spacing-md) 0;
}

.exercise-option {
  padding: var(--spacing-md);
  background: var(--bg-card);
  border: 2px solid var(--border-color);
  border-radius: var(--border-radius-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
  font-size: var(--font-size-base);
}

.exercise-option:hover {
  border-color: var(--primary-color);
  background: var(--bg-hover);
}

.exercise-option.selected {
  border-color: var(--primary-color);
  background: var(--primary-light);
  color: var(--text-white);
}

.exercise-option.correct {
  border-color: var(--secondary-color);
  background: var(--secondary-color);
  color: var(--text-white);
}

.exercise-option.incorrect {
  border-color: var(--accent-color);
  background: var(--accent-color);
  color: var(--text-white);
}

.exercise-option:disabled {
  cursor: not-allowed;
  opacity: 0.7;
}

.exercise-feedback {
  padding: var(--spacing-md);
  border-radius: var(--border-radius-sm);
  margin-top: var(--spacing-md);
  font-weight: 500;
}

.exercise-feedback.correct {
  background: var(--secondary-color);
  color: var(--text-white);
}

.exercise-feedback.incorrect {
  background: var(--accent-color);
  color: var(--text-white);
}

/* Make buttons stand out inside exercise feedback */
.exercise-feedback .btn {
  background: var(--bg-card);
  color: var(--text-primary);
  border: 2px solid rgba(255, 255, 255, 0.3);
  font-weight: 600;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
}

.exercise-feedback .btn:hover {
  background: var(--text-white);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.exercise-feedback.correct .btn-success {
  background: var(--text-white);
  color: var(--secondary-color);
  border-color: var(--text-white);
}

.exercise-feedback.correct .btn-success:hover {
  background: var(--bg-card);
  color: var(--secondary-dark);
}

/* ==================== TOOLTIPS ==================== */
/* Custom tooltips that appear instantly */
[data-tooltip] {
  position: relative;
  cursor: pointer;
}

[data-tooltip]::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(-8px);
  background: rgba(0, 0, 0, 0.9);
  color: var(--text-white);
  padding: 8px 12px;
  border-radius: 6px;
  font-size: 13px;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.15s ease;
  z-index: 1000;
}

[data-tooltip]::before {
  content: '';
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(-2px);
  border: 5px solid transparent;
  border-top-color: rgba(0, 0, 0, 0.9);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.15s ease;
  z-index: 1000;
}

[data-tooltip]:hover::after,
[data-tooltip]:hover::before {
  opacity: 1;
}

/* ==================== UTILITY CLASSES ==================== */
.text-center {
  text-align: center;
}

.text-left {
  text-align: left;
}

.text-right {
  text-align: right;
}

.text-primary {
  color: var(--primary-color);
}

.text-secondary {
  color: var(--text-secondary);
}

.text-success {
  color: var(--secondary-color);
}

.text-danger {
  color: var(--accent-color);
}

.font-weight-bold {
  font-weight: 700;
}

.font-weight-semibold {
  font-weight: 600;
}

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: var(--spacing-xs); }
.mt-2 { margin-top: var(--spacing-sm); }
.mt-3 { margin-top: var(--spacing-md); }
.mt-4 { margin-top: var(--spacing-lg); }

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: var(--spacing-xs); }
.mb-2 { margin-bottom: var(--spacing-sm); }
.mb-3 { margin-bottom: var(--spacing-md); }
.mb-4 { margin-bottom: var(--spacing-lg); }

.hidden {
  display: none !important;
}

.visible {
  visibility: visible;
}

.invisible {
  visibility: hidden;
}

/* ==================== AUTH ==================== */

/* Nav button */
.nav-auth {
  display: flex;
  align-items: center;
  margin-left: var(--spacing-sm);
  position: relative;
}

.auth-nav-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border: 1.5px solid var(--border-color);
  border-radius: 999px;
  background: transparent;
  color: var(--text-secondary);
  font-size: var(--font-size-sm);
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.auth-nav-btn:hover {
  border-color: var(--primary-color);
  color: var(--primary-color);
}

.auth-nav-btn.signed-in {
  border-color: var(--secondary-color);
  color: var(--secondary-color);
}

.auth-nav-icon {
  font-size: 16px;
  line-height: 1;
}

/* Account dropdown */
.auth-account-menu {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  background: white;
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-md);
  min-width: 200px;
  z-index: 2000;
  padding: var(--spacing-sm);
}

.auth-account-email {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  padding: 4px 8px 8px;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 6px;
  word-break: break-all;
}

.auth-signout-btn {
  width: 100%;
  padding: 8px 12px;
  text-align: left;
  background: transparent;
  border: none;
  border-radius: 6px;
  color: var(--accent-color);
  font-size: var(--font-size-sm);
  font-weight: 500;
  cursor: pointer;
  transition: background var(--transition-fast);
}

.auth-signout-btn:hover {
  background: var(--bg-secondary);
}

/* Auth modal overlay */
.auth-modal-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
  z-index: 3000;
  align-items: center;
  justify-content: center;
  padding: 16px;
  box-sizing: border-box;
}

.auth-modal-overlay.active {
  display: flex;
}

/* Auth modal box */
.auth-modal {
  background: white;
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-lg);
  padding: 32px;
  width: 100%;
  max-width: 480px;
  position: relative;
  animation: fadeInUp 0.2s ease;
  box-sizing: border-box;
}

.auth-modal h2 {
  margin: 0 0 6px;
  font-size: var(--font-size-xl);
  color: var(--text-primary);
}

.auth-modal-subtitle {
  margin: 0 0 20px;
  color: var(--text-secondary);
  font-size: var(--font-size-sm);
}

.auth-modal-close {
  position: absolute;
  top: 14px;
  right: 16px;
  background: transparent;
  border: none;
  font-size: 22px;
  color: var(--text-secondary);
  cursor: pointer;
  line-height: 1;
  padding: 2px 6px;
  border-radius: 4px;
  transition: background var(--transition-fast);
}

.auth-modal-close:hover {
  background: var(--bg-secondary);
}

/* Auth form — each field group is label + input, stacked with consistent gap */
.auth-form {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.auth-form label {
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 4px;
  display: block;
}

.auth-form input {
  display: block;
  width: 100%;
  padding: 10px 12px;
  border: 1.5px solid var(--border-color);
  border-radius: 8px;
  font-size: var(--font-size-base);
  color: var(--text-primary);
  background: white;
  transition: border-color var(--transition-fast);
  box-sizing: border-box;
  margin-bottom: 14px;
}

.auth-form input:focus {
  outline: none;
  border-color: var(--primary-color);
}

.auth-error {
  font-size: var(--font-size-sm);
  color: var(--accent-color);
  min-height: 18px;
  margin: 0 0 8px;
}

.auth-submit-btn {
  width: 100%;
  margin-top: 4px;
}

/* Switch mode */
.auth-switch {
  margin: 16px 0 0;
  text-align: center;
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
}

.auth-switch a {
  color: var(--primary-color);
  font-weight: 500;
  text-decoration: none;
  margin-left: 4px;
}

.auth-switch a:hover {
  text-decoration: underline;
}

/* Signup-only fields */
.auth-signup-fields {
  padding-bottom: 14px;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 14px;
}

.auth-name-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.auth-name-col {
  display: flex;
  flex-direction: column;
  flex: 1;
  min-width: 140px;
}

.auth-name-col input {
  width: 100%;
}

.auth-required {
  color: var(--accent-color);
  font-size: 12px;
}

.auth-optional {
  color: var(--text-secondary);
  font-size: 12px;
  font-weight: 400;
}

.auth-field-hint {
  margin: -10px 0 6px;
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
}

/* Goal select */
.auth-form select {
  display: block;
  width: 100%;
  padding: 10px 12px;
  border: 1.5px solid var(--border-color);
  border-radius: 8px;
  font-size: var(--font-size-base);
  color: var(--text-primary);
  background: white;
  transition: border-color var(--transition-fast);
  box-sizing: border-box;
  margin-bottom: 14px;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%236b7280' stroke-width='2'%3E%3Cpolyline points='6 9 12 15 18 9'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 36px;
  cursor: pointer;
}

.auth-form select:focus {
  outline: none;
  border-color: var(--primary-color);
}

/* Password field with toggle */
.auth-password-wrapper {
  position: relative;
  margin-bottom: 14px;
}

.auth-password-wrapper input {
  margin-bottom: 0;
  padding-right: 44px;
}

.auth-password-toggle {
  position: absolute;
  right: 10px;
  top: 50%;
  transform: translateY(-50%);
  background: transparent;
  border: none;
  cursor: pointer;
  color: var(--text-secondary);
  padding: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 4px;
  transition: color var(--transition-fast);
}

.auth-password-toggle:hover {
  color: var(--text-primary);
}

/* ==================== ANIMATIONS ==================== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.8);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

.animate-fade-in-up {
  animation: fadeInUp var(--transition-base);
}

.animate-fade-in-down {
  animation: fadeInDown var(--transition-base);
}

.animate-scale-in {
  animation: scaleIn var(--transition-base);
}