:root {
  --color-primary: #0d6efd;
  --color-primary-hover: #0b5ed7;
  --color-secondary: #6c757d;
  --color-secondary-hover: #5a6268;
  --color-success: #198754;
  --color-success-hover: #157347;
  --color-danger: #dc3545;
  --color-danger-hover: #c82333;

  --color-text-body: #212529;
  --color-text-muted: #6c757d;
  --color-text-emphasis: #495057;
  --color-text-header: #343a40;
  --color-text-light: #fff;

  --color-bg-body: #f8f9fa;
  --color-bg-surface: #fff;
  --color-bg-muted: #e9ecef;
  --color-bg-input-disabled: #f8f9fa;

  --color-border: #dee2e6;
  --color-border-light: #e9ecef;
  --color-border-input: #ced4da;
  --color-border-focus: #80bdff;
  --color-border-focus-alt: #7abaff;

  --shadow-focus: 0 0 0 3px rgba(13, 110, 253, 0.15);
  --shadow-card: 0 6px 20px rgba(0, 0, 0, 0.07);
  --shadow-drag: 0 2px 5px rgba(0, 0, 0, 0.1);

  --font-family-sans-serif: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-family-monospace: Consolas, Monaco, "Andale Mono", "Ubuntu Mono", monospace;
  --font-size-base: 1rem;
  --font-size-sm: 0.8rem;
  --font-size-xs: 0.7em;
  --font-size-input: 0.95rem;
  --font-size-h1: 1.75rem;
  --font-size-h2: 1.1rem;
  --font-size-h4: 1rem;
  --font-size-code: 0.85em;
  --line-height-base: 1.5;

  --border-width: 1px;
  --border-radius-xs: 3px;
  --border-radius-sm: 5px;
  --border-radius-md: 6px;
  --border-radius-lg: 8px;
  --border-radius-xl: 10px;

  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 10px;
  --spacing-lg: 12px;
  --spacing-xl: 15px;
  --spacing-xxl: 20px;
  --spacing-xxxl: 25px;
  --spacing-xxxxl: 30px;
  --spacing-xxxxxl: 35px;

  --transition-fast: 0.2s ease;
  --transition-medium: 0.3s ease;
  --transition-transform: 0.2s ease-in-out;

  --textarea-height: 300px;
  --help-scroll-max-height: 300px;
  --modal-textarea-min-height: 150px;
}

body.dark-theme {
    --color-text-body: #e9ecef;
    --color-text-muted: #adb5bd;
    --color-text-emphasis: #ced4da;
    --color-text-header: #f8f9fa;
    --color-text-light: #f8f9fa;

    --color-bg-body: #212529;
    --color-bg-surface: #343a40;
    --color-bg-muted: #495057;
    --color-bg-input-disabled: #495057;

    --color-border: #495057;
    --color-border-light: #6c757d;
    --color-border-input: #6c757d;
    --color-border-focus: #0d6efd;
    --color-border-focus-alt: #0b5ed7;

    --shadow-focus: 0 0 0 3px rgba(13, 110, 253, 0.3);
    --shadow-card: 0 6px 20px rgba(0, 0, 0, 0.2);
}

body {
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0;
  padding: var(--spacing-xxl);
  min-height: 100vh;
  box-sizing: border-box;
  font-family: var(--font-family-sans-serif);
  background-color: var(--color-bg-body);
  color: var(--color-text-body);
  transition: background-color var(--transition-medium), color var(--transition-medium);
}

.app-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 90%;
  max-width: 1000px;
  padding: var(--spacing-xxxxl);
  background-color: var(--color-bg-surface);
  border-radius: var(--border-radius-xl);
  box-shadow: var(--shadow-card);
  transition: background-color var(--transition-medium);
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    margin-bottom: var(--spacing-xxxxxl);
}

h1 {
  text-align: center;
  margin: 0;
  color: var(--color-text-header);
  font-size: var(--font-size-h1);
}

.theme-switcher {
    display: flex;
    align-items: center;
}

#theme-toggle-button {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1.5rem;
    padding: 0;
    margin: 0;
    color: var(--color-text-body);
}

.version-info {
  margin-left: var(--spacing-sm);
  vertical-align: middle;
  color: var(--color-text-muted);
  font-size: var(--font-size-xs);
}

.text-areas-container {
  display: flex;
  justify-content: space-between;
  width: 100%;
  gap: var(--spacing-xxxl);
  margin-bottom: var(--spacing-xxl);
}

.text-area-wrapper {
  flex: 1;
  display: flex;
  flex-direction: column;
}

.label-button-wrapper {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--spacing-sm);
}

label {
  margin-bottom: 0;
  color: var(--color-text-emphasis);
  font-weight: bold;
}

.text-area-action-button {
  padding: var(--spacing-xs) var(--spacing-md);
  background-color: transparent;
  color: var(--color-text-muted);
  border: var(--border-width) solid var(--color-border-input);
  border-radius: var(--border-radius-sm);
  font-size: var(--font-size-sm);
  cursor: pointer;
  transition: background-color var(--transition-fast), color var(--transition-fast);
}

.text-area-action-button:hover {
  background-color: var(--color-secondary-hover);
  color: var(--color-text-light);
}

textarea {
  width: 100%;
  height: var(--textarea-height);
  padding: var(--spacing-xl);
  box-sizing: border-box;
  font-size: var(--font-size-base);
  line-height: var(--line-height-base);
  border: var(--border-width) solid var(--color-border);
  border-radius: var(--border-radius-md);
  resize: vertical;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast), background-color var(--transition-medium), color var(--transition-medium);
  background-color: var(--color-bg-surface);
  color: var(--color-text-body);
}

textarea:focus {
  outline: none;
  border-color: var(--color-border-focus);
  box-shadow: var(--shadow-focus);
}

#output-text {
  background-color: var(--color-bg-input-disabled);
}

#regex-list-container {
  width: 100%;
  margin-bottom: var(--spacing-xxl);
  background-color: var(--color-bg-surface);
  border: var(--border-width) solid var(--color-border-light);
  border-radius: var(--border-radius-xl);
  transition: background-color var(--transition-medium), border-color var(--transition-medium);
}

.regex-list-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-xl) var(--spacing-xl) 0 var(--spacing-xl);
}

.regex-list-header h2 {
  margin-top: 0;
  margin-bottom: 0;
  color: var(--color-text-header);
  font-size: var(--font-size-h2);
}

.regex-help-examples {
  margin: 0 var(--spacing-xl) var(--spacing-xl) var(--spacing-xl);
  padding: 0;
  background-color: var(--color-bg-body);
  border: var(--border-width) solid var(--color-border-light);
  border-radius: var(--border-radius-md);
  transition: background-color var(--transition-medium), border-color var(--transition-medium);
}

.regex-help-examples h4 {
  margin: 0;
  padding: var(--spacing-md) var(--spacing-xl) var(--spacing-md) var(--spacing-xxxxxl);
  color: var(--color-text-emphasis);
  font-size: var(--font-size-h4);
  font-weight: 500;
  border-bottom: var(--border-width) solid var(--color-border);
  transition: color var(--transition-medium), border-color var(--transition-medium);
}

.collapsible-header {
  position: relative;
  cursor: pointer;
  user-select: none;
}

.collapsible-header::before {
  content: "▶";
  position: absolute;
  left: var(--spacing-xl);
  top: 50%;
  transform: translateY(-50%);
  transition: transform var(--transition-transform);
}

.regex-help-examples:not(.collapsed) .collapsible-header::before {
  transform: translateY(-50%) rotate(90deg);
}

.help-scroll-area {
  max-height: var(--help-scroll-max-height);
  margin-top: var(--spacing-xl);
  padding: var(--spacing-xl);
  overflow-y: auto;
  background-color: var(--color-bg-surface);
  transition: background-color var(--transition-medium);
}

.regex-help-examples.collapsed .help-scroll-area {
  display: none;
}

.regex-help-examples .help-scroll-area dl {
  margin-top: 0;
  margin-bottom: 0;
  color: var(--color-text-emphasis);
  font-size: var(--font-size-code);
}

.regex-help-examples dt {
  margin-top: var(--spacing-md);
  font-weight: 600;
}

.regex-help-examples dd {
  margin-left: var(--spacing-xl);
  margin-bottom: var(--spacing-xs);
}

.regex-help-examples code {
  padding: 2px var(--spacing-xs);
  font-family: var(--font-family-monospace);
  background-color: var(--color-bg-muted);
  border: none;
  border-radius: var(--border-radius-xs);
  color: var(--color-text-body);
  transition: background-color var(--transition-medium), color var(--transition-medium);
}

#regex-items-wrapper {
  padding: var(--spacing-xl);
  padding-top: 0;
}

.regex-row {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
}

.drag-handle {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 var(--spacing-md);
  color: var(--color-text-muted);
  cursor: move;
}

.drag-handle::before {
  content: "☰";
  font-size: 1.2em;
}

.regex-row label {
  display: none;
}

.regex-row .regex-input-wrapper {
  flex: 1;
  display: flex;
  flex-direction: column;
}

input[type="text"] {
  padding: var(--spacing-md);
  box-sizing: border-box;
  font-size: var(--font-size-input);
  border: var(--border-width) solid var(--color-border-input);
  border-radius: var(--border-radius-md);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast), background-color var(--transition-medium), color var(--transition-medium);
  background-color: var(--color-bg-surface);
  color: var(--color-text-body);
}

input[type="text"]:focus {
  outline: none;
  border-color: var(--color-border-focus-alt);
  box-shadow: var(--shadow-focus);
}

.regex-row select {
  padding: calc(var(--spacing-md) - 1px);
  font-size: var(--font-size-input);
  background-color: var(--color-bg-surface);
  border: var(--border-width) solid var(--color-border-input);
  border-radius: var(--border-radius-md);
  color: var(--color-text-body);
  transition: background-color var(--transition-medium), color var(--transition-medium), border-color var(--transition-medium);
}

.delete-pattern-button {
  align-self: center;
  height: fit-content;
  padding: var(--spacing-xs) var(--spacing-md);
  color: var(--color-text-light);
  background-color: var(--color-danger);
  border: none;
  border-radius: var(--border-radius-md);
  font-size: var(--font-size-sm);
  cursor: pointer;
  transition: background-color var(--transition-medium);
}

.delete-pattern-button:hover {
  background-color: var(--color-danger-hover);
}

.regex-list-actions {
  display: flex;
  gap: var(--spacing-md);
}

.regex-list-actions button {
  padding: var(--spacing-xs) var(--spacing-md);
  border: 1px solid transparent;
  border-radius: var(--border-radius-lg);
  font-size: var(--font-size-sm);
  cursor: pointer;
  transition: background-color var(--transition-fast);
}

.button-container {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  width: 100%;
  gap: var(--spacing-xl);
  margin-top: var(--spacing-xxxl);
}

.button-container button {
  padding: var(--spacing-lg) var(--spacing-xxxl);
  color: var(--color-text-light);
  border: none;
  border-radius: var(--border-radius-md);
  font-size: var(--font-size-base);
  cursor: pointer;
  transition: background-color var(--transition-medium);
}

#add-pattern-button,
#save-patterns-button,
#load-patterns-button,
#export-json-clipboard-button,
#import-json-clipboard-button {
  color: var(--color-text-light);
  background-color: var(--color-success);
}

#add-pattern-button:hover,
#save-patterns-button:hover,
#load-patterns-button:hover,
#export-json-clipboard-button:hover,
#import-json-clipboard-button:hover {
  background-color: var(--color-success-hover);
}

#apply-patterns-button {
  background-color: var(--color-primary);
}

#apply-patterns-button:hover {
  background-color: var(--color-primary-hover);
}

.secondary-button {
  background-color: var(--color-secondary);
}

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

.secondary-button:disabled {
  background-color: var(--color-text-muted);
  cursor: not-allowed;
}

.modal {
  display: none;
  position: fixed;
  z-index: 1000;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  overflow: auto;
  background-color: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(3px);
}

.modal-content {
  background-color: var(--color-bg-surface);
  margin: 10% auto;
  padding: var(--spacing-xxl);
  border: var(--border-width) solid var(--color-border);
  width: 90%;
  max-width: 600px;
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-card);
  position: relative;
  animation: fadeInModal 0.3s ease-out;
  transition: background-color var(--transition-medium), border-color var(--transition-medium);
}

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

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.modal-close-button {
  color: var(--color-text-muted);
  position: absolute;
  top: var(--spacing-md);
  right: var(--spacing-lg);
  font-size: 28px;
  font-weight: bold;
  line-height: 1;
}

.modal-close-button:hover,
.modal-close-button:focus {
  color: var(--color-text-body);
  text-decoration: none;
  cursor: pointer;
}

.modal-content h2 {
  margin-top: 0;
  margin-bottom: var(--spacing-lg);
  font-size: var(--font-size-h2);
  color: var(--color-text-header);
}

.modal-content p {
  margin-bottom: var(--spacing-md);
  font-size: 0.9rem;
  color: var(--color-text-emphasis);
}

#json-import-textarea {
  width: 100%;
  padding: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
  border: var(--border-width) solid var(--color-border-input);
  border-radius: var(--border-radius-md);
  font-family: var(--font-family-monospace);
  font-size: 0.9rem;
  box-sizing: border-box;
  resize: vertical;
  min-height: var(--modal-textarea-min-height);
  background-color: var(--color-bg-surface);
  color: var(--color-text-body);
  transition: background-color var(--transition-medium), color var(--transition-medium), border-color var(--transition-medium);
}

.modal-actions {
  margin-top: var(--spacing-xl);
  text-align: right;
}

.modal-actions button {
  padding: var(--spacing-md) var(--spacing-xl);
  background-color: var(--color-primary);
  color: var(--color-text-light);
  border: none;
  border-radius: var(--border-radius-md);
  cursor: pointer;
  font-size: var(--font-size-base);
  transition: background-color var(--transition-medium);
}

.modal-actions button:hover {
  background-color: var(--color-primary-hover);
}

@media (max-width: 800px) {
  .text-areas-container {
    flex-direction: column;
    gap: var(--spacing-xxxxl);
  }

  .regex-row {
    flex-direction: row;
    gap: var(--spacing-sm);
  }

  .regex-row input[type="text"],
  .regex-row select {
    font-size: 0.9rem;
    padding: calc(var(--spacing-md) - 1px);
  }

  .delete-pattern-button {
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: 0.75rem;
  }

  .regex-list-actions button {
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: var(--font-size-sm);
  }

  .text-area-action-button {
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: 0.75rem;
  }

  .button-container {
    flex-direction: column;
    width: 100%;
    align-items: stretch;
  }

  .button-container button {
    margin-bottom: var(--spacing-md);
  }

  textarea {
    height: 250px;
  }

  .app-container {
    width: 95%;
    padding: var(--spacing-xxl);
  }

  h1 {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-xxl);
  }

  .modal-content {
    margin: 5% auto;
    padding: var(--spacing-xl);
  }

  #json-import-textarea {
    min-height: 100px;
  }
}

footer {
  width: 100%;
  margin-top: var(--spacing-xxxxl);
  text-align: center;
  color: var(--color-text-muted);
  font-size: 0.9rem;
}

.sortable-ghost {
  opacity: 0.4;
  background-color: var(--color-bg-muted);
  border: var(--border-width) dashed var(--color-border-input);
}

.sortable-chosen,
.sortable-drag {
  background-color: var(--color-border);
  box-shadow: var(--shadow-drag);
}

.sortable-drag .drag-handle {
  cursor: grabbing;
}