/*
 * AGPL-3.0-or-later License - See LICENSE file for full text
 * Copyright (c) 2026 Mike Gifford
 * 
 * A11y Mermaid Studio Styles
 * Light/dark mode support with accessible color contrasts
 */

:root {
  --color-bg: #ffffff;
  --color-text: #1a1a1a;
  --color-border: #d0d0d0;
  --color-primary: #0066cc;
  --color-primary-hover: #0052a3;
  --color-success: #22863a;
  --color-error: #cb2431;
  --color-info: #1f6feb;
  --color-focus: #0066cc;
  
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  --font-size-base: 16px;
  --font-size-sm: 14px;
  --font-size-lg: 18px;
  
  --contrast-ratio: 7:1;
  --focus-ring-width: 3px;
  --focus-ring-color: var(--color-focus);
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #1a1a1a;
    --color-text: #ffffff;
    --color-border: #333333;
    --color-primary: #4da6ff;
    --color-primary-hover: #66b3ff;
    --color-success: #34d399;
    --color-error: #f85149;
  }
}

html[data-theme="dark"] {
  --color-bg: #1a1a1a;
  --color-text: #ffffff;
  --color-border: #333333;
  --color-primary: #4da6ff;
  --color-primary-hover: #66b3ff;
  --color-success: #34d399;
  --color-error: #f85149;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: 1.6;
}

body {
  background-color: var(--color-bg);
  color: var(--color-text);
  transition: background-color 0.3s ease, color 0.3s ease;
}

/* Skip to main content link */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--color-primary);
  color: white;
  padding: var(--space-sm) var(--space-md);
  text-decoration: none;
  z-index: 100;
}

.skip-link:focus {
  top: 0;
}

/* Main container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--space-lg);
}

/* Header */
header {
  background-color: var(--color-bg);
  border-bottom: 2px solid var(--color-border);
  padding: var(--space-lg) 0;
  margin-bottom: var(--space-xl);
}

.header-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-lg);
}

.top-actions {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-left: auto;
}

.note {
  margin: 0 auto var(--space-lg);
  padding: var(--space-sm) var(--space-md);
  text-align: center;
  color: var(--color-text);
}

.top-actions button {
  padding: var(--space-sm) var(--space-md);
  font-size: var(--font-size-sm);
}

h1 {
  margin: 0 0 var(--space-sm) 0;
  font-size: 28px;
  font-weight: 600;
}

.subtitle {
  margin: 0;
  font-size: var(--font-size-sm);
  color: var(--color-text);
  opacity: 0.8;
}

/* Theme toggle button */
#theme-toggle-btn {
  min-width: 64px;
  padding: var(--space-sm) var(--space-md);
  background: var(--color-border);
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

#theme-toggle-btn[aria-pressed="true"] {
  background: var(--color-text);
  color: var(--color-bg);
  border-color: var(--color-text);
}

/* Form elements */
textarea,
input {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  padding: var(--space-md);
  border: 2px solid var(--color-border);
  border-radius: 4px;
  background-color: var(--color-bg);
  color: var(--color-text);
  transition: border-color 0.2s;
}

textarea:focus,
input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 var(--focus-ring-width) rgba(0, 102, 204, 0.2);
}

textarea {
  width: 100%;
  min-height: 200px;
  font-family: 'Monaco', 'Menlo', 'Courier New', monospace;
  font-size: var(--font-size-sm);
  resize: vertical;
}

.pane textarea {
  min-height: 320px;
  flex: 1;
}

/* Buttons */
button {
  padding: var(--space-md) var(--space-lg);
  font-size: var(--font-size-base);
  font-weight: 500;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.2s;
  background-color: var(--color-primary);
  color: white;
}

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

button:focus {
  outline: none;
  box-shadow: 0 0 0 var(--focus-ring-width) rgba(0, 102, 204, 0.4);
}

button:active {
  transform: scale(0.98);
}

button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* Status messages */
#status {
  padding: var(--space-md);
  border-radius: 4px;
  margin-bottom: var(--space-lg);
  min-height: 1em;
  display: flex;
  align-items: center;
}

#status.error {
  background-color: rgba(203, 36, 49, 0.1);
  color: var(--color-error);
  border: 1px solid var(--color-error);
}

#status:not(.error):not(:empty) {
  background-color: rgba(34, 134, 58, 0.1);
  color: var(--color-success);
  border: 1px solid var(--color-success);
}

/* Code split layout */
.code-split {
  --split-left: 50%;
  --split-right: 50%;
  display: grid;
  grid-template-columns: var(--split-left) 12px var(--split-right);
  gap: var(--space-md);
  align-items: stretch;
  margin-bottom: var(--space-xl);
}

.pane {
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: var(--space-md);
  background: var(--color-bg);
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.pane-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-sm);
}

.svg-controls {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.mode-toggle {
  display: flex;
  gap: var(--space-sm);
  font-size: var(--font-size-sm);
}

.mode-toggle label {
  display: flex;
  align-items: center;
  gap: 4px;
  cursor: pointer;
  padding: 4px 8px;
  border-radius: 4px;
  transition: background-color 0.2s;
}

.mode-toggle label .size-hint {
  font-size: 11px;
  opacity: 0.7;
  margin-left: 4px;
  font-weight: normal;
}

.mode-toggle label:hover {
  background-color: rgba(0, 102, 204, 0.1);
}

.mode-toggle input[type="radio"] {
  margin: 0;
  cursor: pointer;
}

.help-text {
  margin: 0;
  font-size: var(--font-size-sm);
  opacity: 0.8;
}

.code-shell {
  position: relative;
  font-family: 'SFMono-Regular', Menlo, Monaco, Consolas, 'Liberation Mono', 'Courier New', monospace;
  font-size: 14px;
  line-height: 1.5;
  min-height: 320px;
  height: 360px;
}

#svg-code-highlight {
  position: absolute;
  inset: 0;
  margin: 0;
  padding: var(--space-sm);
  background: #0b1021;
  color: #e5e9f0;
  white-space: pre-wrap;
  word-break: break-word;
  overflow: auto;
  border: 1px solid var(--color-border);
  border-radius: 4px;
  pointer-events: none;
  z-index: 0;
}

#svg-code {
  position: relative;
  z-index: 1;
  width: 100%;
  height: 100%;
  min-height: 320px;
  padding: var(--space-sm);
  background: transparent;
  color: transparent;
  caret-color: var(--color-text);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  font-family: 'SFMono-Regular', Menlo, Monaco, Consolas, 'Liberation Mono', 'Courier New', monospace;
  font-size: 14px;
  line-height: 1.5;
  resize: vertical;
}

#svg-code:focus {
  outline: none;
  box-shadow: 0 0 0 var(--focus-ring-width) rgba(0, 102, 204, 0.3);
}

.hl-tag { color: #88c0d0; }
.hl-attr { color: #d8dee9; }
.hl-aria { color: #a3be8c; font-weight: 600; }
.hl-style { color: #ebcb8b; }
.hl-text { color: #eceff4; }
.hl-comment { color: #616e88; font-style: italic; }

.toggle-inline {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.splitter {
  width: 12px;
  cursor: col-resize;
  background: linear-gradient(90deg, transparent 0%, var(--color-border) 50%, transparent 100%);
  border-radius: 6px;
}

.splitter:focus,
.splitter:hover {
  outline: none;
  box-shadow: 0 0 0 var(--focus-ring-width) rgba(0, 102, 204, 0.2);
  background: linear-gradient(90deg, transparent 0%, var(--color-primary) 50%, transparent 100%);
}

.button-row {
  display: flex;
  gap: var(--space-sm);
  justify-content: flex-end;
}

@media (max-width: 900px) {
  .code-split {
    grid-template-columns: 1fr;
  }
  .splitter {
    display: none;
  }
}

@media (max-width: 720px) {
  .header-row {
    flex-direction: column;
    align-items: flex-start;
  }
  .top-actions {
    width: 100%;
    justify-content: flex-start;
  }
}

/* Preview section */
.preview-section {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.preview-section h2 {
  margin: 0 0 var(--space-md) 0;
  font-size: var(--font-size-lg);
}

/* Split preview (light/dark) */
.preview-split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
}

@media (max-width: 1400px) {
  .preview-split {
    grid-template-columns: 1fr;
  }
}

.preview-pane {
  border: 1px solid var(--color-border);
  border-radius: 4px;
  padding: var(--space-lg);
  min-height: 300px;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: var(--color-bg);
}

.preview-pane[id="preview-light"] {
  background-color: #ffffff;
  color: #1a1a1a;
}

.preview-pane[id="preview-dark"] {
  background-color: #1a1a1a;
  color: #ffffff;
}

.preview-pane svg {
  max-width: 100%;
  height: auto;
  min-height: 240px;
  display: block;
}

.preview-pane:empty::before {
  content: 'Render a diagram to see preview';
  opacity: 0.5;
  font-size: var(--font-size-sm);
}

.preview-label {
  margin: 0 0 0.5rem 0;
  font-size: 14px;
  opacity: 0.8;
}

/* Editor inline error display */
.editor-error {
  margin-top: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  border-radius: 4px;
  font-size: var(--font-size-sm);
  color: var(--color-error);
  background-color: rgba(203, 36, 49, 0.08);
  border: 1px solid rgba(203, 36, 49, 0.3);
  display: none;
}

.editor-error.show {
  display: block;
}

/* Footer */
footer {
  border-top: 1px solid var(--color-border);
  padding: var(--space-lg) 0;
  margin-top: var(--space-xl);
  font-size: var(--font-size-sm);
  opacity: 0.8;
}

/* Accessibility utilities */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

.render-help {
  margin-top: 0.5rem;
  border: 1px solid var(--color-border);
  background: var(--color-bg-muted, #f8f8f8);
  border-radius: 4px;
  padding: 0.5rem 0.75rem;
  font-size: 0.95rem;
}

.render-help summary {
  cursor: pointer;
  font-weight: 600;
}

.render-help ul {
  margin: 0.25rem 0 0 1rem;
  padding: 0;
  list-style: disc;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* Toast notifications */
.toast-container {
  position: fixed;
  top: 16px;
  right: 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  z-index: 1100;
}

.toast {
  display: flex;
  align-items: start;
  justify-content: space-between;
  gap: 12px;
  background: var(--color-bg);
  color: var(--color-text);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: 12px 12px 12px 14px;
  box-shadow: 0 6px 16px rgba(0,0,0,0.18);
  min-width: 280px;
  max-width: 480px;
}

.toast-message.info { color: var(--color-info); font-weight: 600; }
.toast-message.success { color: var(--color-success); font-weight: 600; }
.toast-message.error { color: var(--color-error); font-weight: 600; }

.toast-close {
  background: transparent;
  border: none;
  color: var(--color-text);
  font-size: 20px;
  line-height: 1;
  padding: 4px 6px;
  cursor: pointer;
}

.toast-close:hover { opacity: 0.75; }

/* Modal styles */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
}

.modal {
  background: var(--color-bg);
  color: var(--color-text);
  width: min(520px, 92vw);
  border: 2px solid var(--color-border);
  border-radius: 6px;
  padding: var(--space-lg);
  box-shadow: 0 10px 24px rgba(0,0,0,0.25);
}

#modal-message.info {
  color: var(--color-info);
  font-weight: 600;
}

#modal-message.success {
  color: var(--color-success);
  font-weight: 600;
}

#modal-message.error {
  color: var(--color-error);
  font-weight: 600;
}

/* Print styles */
@media print {
  .editor-section,
  .toolbar,
  footer {
    display: none;
  }
  
  .preview-split {
    grid-template-columns: 1fr;
  }
  
  .preview-pane[id="preview-dark"] {
    display: none;
  }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}