:root {
  font-family: system-ui, Avenir, Helvetica, Arial, sans-serif;
  line-height: 1.5;
  font-weight: 400;

  color-scheme: light dark;
  color: rgba(255, 255, 255, 0.87);
  background-color: #242424;

  font-synthesis: none;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  font-weight: 500;
  color: #646cff;
  text-decoration: inherit;
}
a:hover {
  color: #535bf2;
}

body {
  margin: 0;
  display: flex;
  place-items: center;
  min-width: 320px;
  min-height: 100vh;
}

h1 {
  font-size: 3.2em;
  line-height: 1.1;
}

button {
  border-radius: 8px;
  border: 1px solid transparent;
  padding: 0.6em 1.2em;
  font-size: 1em;
  font-weight: 500;
  font-family: inherit;
  background-color: #1a1a1a;
  cursor: pointer;
  transition: border-color 0.25s;
}
button:hover {
  border-color: #646cff;
}
button:focus,
button:focus-visible {
  outline: 4px auto -webkit-focus-ring-color;
}

.card {
  padding: 2em;
}

#app {
  max-width: 1280px;
  margin: 0 auto;
  padding: 2rem;
  text-align: center;
}

/* Layout */
.editor-container {
  display: flex;
  flex-direction: row;
  height: 100vh;
  width: 100%;
}
@media (max-width: 768px) {
  .editor-container {
    flex-direction: column;
  }
}
.editor, .preview {
  flex: 1;
  padding: 1rem;
  box-sizing: border-box;
}

/* Editor textarea */
.editor textarea,
.editor input,
.editor .input {
  border: none;
  outline: none;
  background: transparent;
  line-height: 1.6;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  width: 100%;
  height: 100%;
  resize: none;
}

/* Selection */
.editor ::selection {
  background: rgba(200, 200, 200, 0.3);
}

/* Preview typography */
.preview p {
  line-height: 1.6;
}
.preview h1 { font-size: 2em; }
.preview h2 { font-size: 1.75em; }
.preview h3 { font-size: 1.5em; }
.preview h4 { font-size: 1.25em; }
.preview h5 { font-size: 1em; }
.preview h6 { font-size: 0.875em; }
.preview blockquote {
  border-left: 4px solid #ddd;
  padding-left: 1rem;
  color: #666;
}

/* Tables */
.preview table {
  border-collapse: collapse;
  width: 100%;
}
.preview th,
.preview td {
  border: 1px solid #ccc;
  padding: 0.4rem;
}

/* Code block */
.preview pre,
.preview code {
  background: #f5f5f5;
  border-radius: 4px;
  padding: 0.8rem;
  overflow-x: auto;
}

/* Global */
html,
body {
  margin: 0;
  padding: 0;
  height: 100%;
}

/* CSS variables (to be defined elsewhere) */
:root {
  --bg-color: var(--bg-color);
  --text-color: var(--text-color);
}

/* Light mode overrides (original) */
@media (prefers-color-scheme: light) {
  :root {
    color: #213547;
    background-color: #ffffff;
  }
  a:hover {
    color: #747bff;
  }
  button {
    background-color: #f9f9f9;
  }
}