* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg-primary: #0d1117;
  --bg-secondary: #161b22;
  --bg-tertiary: #1c2128;
  --border-default: #30363d;
  --border-muted: #21262d;
  --text-primary: #e6edf3;
  --text-secondary: #8b949e;
  --text-muted: #6e7681;
  --accent-blue: #58a6ff;
  --accent-green: #3fb950;
  --accent-red: #f85149;
  --accent-orange: #d29922;
  --accent-purple: #bc8cff;
  --accent-pink: #f778ba;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.5);
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: flex-start;
  padding: 2rem 1rem;
  line-height: 1.5;
}

.container {
  width: 100%;
  max-width: 780px;
  background: var(--bg-secondary);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-lg);
}

header {
  margin-bottom: 1.25rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border-muted);
}

.header-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
}

h1 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.board-label {
  font-size: 0.8rem;
  color: var(--text-secondary);
  background: var(--bg-tertiary);
  padding: 0.35rem 0.75rem;
  border-radius: 20px;
  border: 1px solid var(--border-default);
  font-weight: 500;
}

.note-info {
  background: var(--bg-tertiary);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  padding: 0.75rem 1rem;
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  font-size: 0.85rem;
}

.note-info-row {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.note-icon {
  font-size: 0.9rem;
}

.note-text {
  color: var(--accent-blue);
  font-weight: 600;
}

.note-expiry {
  color: var(--accent-orange);
  font-family: 'SF Mono', 'Monaco', 'Consolas', monospace;
  font-size: 0.8rem;
  font-weight: 500;
}

.note-lock {
  font-size: 1.1rem;
  margin-left: auto;
}

.locked-banner {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  background: rgba(248, 81, 73, 0.08);
  border: 1px solid rgba(248, 81, 73, 0.3);
  border-radius: var(--radius-md);
  padding: 0.65rem 1rem;
  margin-bottom: 1rem;
  font-size: 0.82rem;
  color: var(--accent-red);
  flex-wrap: wrap;
}

.locked-banner-icon {
  font-size: 1rem;
}

.locked-banner-text {
  flex: 1;
  font-weight: 500;
}

.editor-wrapper {
  position: relative;
}

.editor-blurred {
  filter: blur(6px);
  user-select: none;
  pointer-events: none;
}

.hidden-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(13, 17, 23, 0.75);
  backdrop-filter: blur(2px);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 0.75rem;
  border-radius: var(--radius-md);
  cursor: pointer;
  z-index: 10;
  transition: opacity 0.3s ease;
}

.hidden-overlay:hover {
  background: rgba(13, 17, 23, 0.6);
}

.hidden-overlay-icon {
  font-size: 2rem;
}

.hidden-overlay-text {
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
}

#editor {
  width: 100%;
  min-height: 320px;
  background: var(--bg-primary);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-size: 0.95rem;
  padding: 1rem 1.25rem;
  resize: vertical;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
  font-family: 'SF Mono', 'Monaco', 'Consolas', 'Courier New', monospace;
  line-height: 1.7;
}

#editor:focus {
  border-color: var(--accent-blue);
  box-shadow: 0 0 0 3px rgba(88, 166, 255, 0.15);
}

#editor::placeholder {
  color: var(--text-muted);
}

.markdown-preview {
  width: 100%;
  min-height: 320px;
  background: var(--bg-primary);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-size: 0.95rem;
  padding: 1rem 1.25rem;
  line-height: 1.7;
  overflow-y: auto;
}

.markdown-preview h1,
.markdown-preview h2,
.markdown-preview h3 {
  color: var(--text-primary);
  margin: 1em 0 0.5em;
  font-weight: 600;
  border-bottom: 1px solid var(--border-muted);
  padding-bottom: 0.3em;
}

.markdown-preview h1 { font-size: 1.6em; }
.markdown-preview h2 { font-size: 1.35em; }
.markdown-preview h3 { font-size: 1.15em; border-bottom: none; }

.markdown-preview p {
  margin: 0.6em 0;
}

.markdown-preview code {
  background: var(--bg-tertiary);
  padding: 0.2em 0.45em;
  border-radius: 4px;
  font-size: 0.88em;
  font-family: 'SF Mono', 'Monaco', 'Consolas', monospace;
  border: 1px solid var(--border-muted);
}

.markdown-preview pre {
  background: var(--bg-tertiary);
  padding: 1rem;
  border-radius: var(--radius-md);
  overflow-x: auto;
  margin: 0.75em 0;
  border: 1px solid var(--border-default);
}

.markdown-preview pre code {
  background: none;
  padding: 0;
  border: none;
}

.markdown-preview a {
  color: var(--accent-blue);
  text-decoration: none;
}

.markdown-preview a:hover {
  text-decoration: underline;
}

.markdown-preview blockquote {
  border-left: 4px solid var(--accent-blue);
  padding-left: 1rem;
  margin: 0.75em 0;
  color: var(--text-secondary);
  background: var(--bg-tertiary);
  padding: 0.5rem 1rem;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.markdown-preview ul,
.markdown-preview ol {
  padding-left: 1.75em;
  margin: 0.6em 0;
}

.markdown-preview li {
  margin: 0.25em 0;
}

.markdown-preview table {
  border-collapse: collapse;
  width: 100%;
  margin: 0.75em 0;
}

.markdown-preview th,
.markdown-preview td {
  border: 1px solid var(--border-default);
  padding: 0.5rem 0.75rem;
  text-align: left;
}

.markdown-preview th {
  background: var(--bg-tertiary);
  font-weight: 600;
}

.markdown-preview tr:nth-child(even) {
  background: var(--bg-tertiary);
}

.toolbar {
  margin-top: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.toolbar-group {
  background: var(--bg-tertiary);
  border: 1px solid var(--border-muted);
  border-radius: var(--radius-md);
  padding: 0.75rem 1rem;
}

.toolbar-label {
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-bottom: 0.6rem;
}

.toolbar-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 1px solid var(--border-default);
  padding: 0.5rem 0.9rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.82rem;
  font-weight: 500;
  transition: all 0.15s ease;
  white-space: nowrap;
}

.btn:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

.btn:active:not(:disabled) {
  transform: translateY(0);
}

.btn:disabled {
  opacity: 0.35;
  cursor: not-allowed;
  pointer-events: none;
}

.btn-primary {
  background: rgba(88, 166, 255, 0.1);
  border-color: rgba(88, 166, 255, 0.4);
  color: var(--accent-blue);
}

.btn-primary:hover:not(:disabled) {
  background: rgba(88, 166, 255, 0.2);
  border-color: var(--accent-blue);
}

.btn-success {
  background: rgba(63, 185, 80, 0.1);
  border-color: rgba(63, 185, 80, 0.4);
  color: var(--accent-green);
}

.btn-success:hover:not(:disabled) {
  background: rgba(63, 185, 80, 0.2);
  border-color: var(--accent-green);
}

.btn-danger {
  background: rgba(248, 81, 73, 0.1);
  border-color: rgba(248, 81, 73, 0.4);
  color: var(--accent-red);
}

.btn-danger:hover:not(:disabled) {
  background: rgba(248, 81, 73, 0.2);
  border-color: var(--accent-red);
}

.btn-warning {
  background: rgba(210, 153, 34, 0.1);
  border-color: rgba(210, 153, 34, 0.4);
  color: var(--accent-orange);
}

.btn-warning:hover:not(:disabled) {
  background: rgba(210, 153, 34, 0.2);
  border-color: var(--accent-orange);
}

.btn-info {
  background: rgba(188, 140, 255, 0.1);
  border-color: rgba(188, 140, 255, 0.4);
  color: var(--accent-purple);
}

.btn-info:hover:not(:disabled) {
  background: rgba(188, 140, 255, 0.2);
  border-color: var(--accent-purple);
}

.btn-purple {
  background: rgba(247, 120, 186, 0.1);
  border-color: rgba(247, 120, 186, 0.4);
  color: var(--accent-pink);
}

.btn-purple:hover:not(:disabled) {
  background: rgba(247, 120, 186, 0.2);
  border-color: var(--accent-pink);
}

.url-section {
  margin-top: 1rem;
  display: flex;
  gap: 0.5rem;
  align-items: stretch;
}

.url-input-wrapper {
  flex: 1;
  display: flex;
  align-items: center;
  background: var(--bg-primary);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-sm);
  padding: 0 0.75rem;
  gap: 0.5rem;
}

.url-icon {
  color: var(--text-muted);
  font-size: 0.9rem;
}

#generated-url {
  flex: 1;
  background: transparent;
  border: none;
  color: var(--accent-blue);
  padding: 0.5rem 0;
  font-size: 0.85rem;
  outline: none;
  font-family: 'SF Mono', 'Monaco', 'Consolas', monospace;
}

.qr-section {
  margin-top: 1rem;
  display: flex;
  justify-content: center;
}

.qr-wrapper {
  background: #fff;
  padding: 1.25rem;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
}

#qr-image {
  max-width: 260px;
  width: 100%;
  display: block;
}

.hidden {
  display: none !important;
}

.toast {
  position: fixed;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border: 1px solid var(--border-default);
  padding: 0.65rem 1.25rem;
  border-radius: var(--radius-md);
  font-size: 0.85rem;
  font-weight: 500;
  z-index: 1000;
  box-shadow: var(--shadow-lg);
  animation: toastSlide 2.5s ease forwards;
}

@keyframes toastSlide {
  0% { opacity: 0; transform: translateX(-50%) translateY(20px); }
  12% { opacity: 1; transform: translateX(-50%) translateY(0); }
  88% { opacity: 1; transform: translateX(-50%) translateY(0); }
  100% { opacity: 0; transform: translateX(-50%) translateY(-10px); }
}

.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(4px);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 999;
  animation: fadeIn 0.2s ease;
}

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

.modal {
  background: var(--bg-secondary);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  width: 90%;
  max-width: 420px;
  box-shadow: var(--shadow-lg);
  animation: modalSlide 0.25s ease;
  overflow: hidden;
}

@keyframes modalSlide {
  from { opacity: 0; transform: translateY(-20px) scale(0.95); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--border-muted);
}

.modal-header h3 {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-primary);
}

.modal-close {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 1.1rem;
  cursor: pointer;
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  transition: all 0.15s;
}

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

.modal-body {
  padding: 1.25rem;
}

.modal-body p {
  color: var(--text-secondary);
  font-size: 0.88rem;
  margin-bottom: 1rem;
  line-height: 1.5;
}

.modal-footer {
  display: flex;
  gap: 0.5rem;
  justify-content: flex-end;
  padding: 1rem 1.25rem;
  border-top: 1px solid var(--border-muted);
  background: var(--bg-tertiary);
}

.form-group {
  margin-bottom: 1rem;
}

.form-group:last-child {
  margin-bottom: 0;
}

.form-group label {
  display: block;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 0.4rem;
}

.form-group input,
.form-group select {
  width: 100%;
  background: var(--bg-primary);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  padding: 0.55rem 0.75rem;
  font-size: 0.88rem;
  outline: none;
  transition: border-color 0.15s, box-shadow 0.15s;
}

.form-group input:focus,
.form-group select:focus {
  border-color: var(--accent-blue);
  box-shadow: 0 0 0 3px rgba(88, 166, 255, 0.15);
}

.form-group input::placeholder {
  color: var(--text-muted);
}

.form-group select {
  cursor: pointer;
}

.checkbox-label {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  cursor: pointer;
  font-size: 0.85rem;
  color: var(--text-primary);
  margin-bottom: 0;
}

.checkbox-label input[type="checkbox"] {
  width: auto;
  accent-color: var(--accent-blue);
  cursor: pointer;
}

.checkbox-label span {
  user-select: none;
}

@media (max-width: 600px) {
  body {
    padding: 1rem 0.5rem;
  }

  .container {
    padding: 1rem;
  }

  h1 {
    font-size: 1.25rem;
  }

  .toolbar-buttons {
    flex-direction: column;
  }

  .btn {
    justify-content: center;
  }

  .url-section {
    flex-direction: column;
  }

  .note-info {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }

  .note-lock {
    margin-left: 0;
  }
}