:root {
  color-scheme: light;
  --bg: #f6f7f9;
  --surface: #ffffff;
  --surface-alt: #eef2f6;
  --text: #18202b;
  --muted: #697386;
  --border: #d7dde6;
  --accent: #0f766e;
  --accent-strong: #0b5f59;
  --danger: #b42318;
  --code-bg: #111827;
  --shadow: 0 12px 30px rgba(24, 32, 43, 0.08);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
}

[data-theme="dark"] {
  color-scheme: dark;
  --bg: #121417;
  --surface: #1b1f24;
  --surface-alt: #242a31;
  --text: #eef2f6;
  --muted: #a8b3c2;
  --border: #343c46;
  --accent: #2dd4bf;
  --accent-strong: #5eead4;
  --danger: #fb7185;
  --shadow: 0 16px 34px rgba(0, 0, 0, 0.24);
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
  overflow: hidden;
}

body {
  margin: 0;
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--text);
}

button,
textarea,
input {
  font: inherit;
}

.app-header {
  flex: 0 0 auto;
  min-height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 8px 14px;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}

.app-header h1 {
  margin: 0;
  font-size: 1.1rem;
  line-height: 1.2;
}

.app-header p {
  margin: 1px 0 0;
  color: var(--muted);
  font-size: 0.8rem;
}

.toolbar {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 6px;
}

button,
.file-button,
.switch {
  min-height: 32px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--surface-alt);
  color: var(--text);
  padding: 0 10px;
  cursor: pointer;
}

button:hover,
.file-button:hover,
.switch:hover {
  border-color: var(--accent);
}

button:focus-visible,
.file-button:focus-within,
.switch:focus-within,
textarea:focus,
.markdown-body:focus {
  outline: 3px solid color-mix(in srgb, var(--accent), transparent 70%);
  outline-offset: 2px;
}

.file-button input {
  position: absolute;
  inline-size: 1px;
  block-size: 1px;
  opacity: 0;
}

.switch input {
  accent-color: var(--accent);
}

.workspace {
  flex: 1 1 auto;
  min-height: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 10px;
  padding: 10px;
}

.pane {
  min-width: 0;
  min-height: 0;
  display: flex;
  flex-direction: column;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.pane-head {
  min-height: 36px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 0 12px;
  border-bottom: 1px solid var(--border);
  background: var(--surface-alt);
  color: var(--muted);
  font-size: 0.86rem;
}

.pane-head h2 {
  margin: 0;
  color: var(--text);
  font-size: 0.92rem;
}

#editor,
.markdown-body {
  flex: 1;
  width: 100%;
  min-height: 0;
  overflow: auto;
}

#editor {
  border: 0;
  resize: none;
  padding: 20px;
  background: var(--surface);
  color: var(--text);
  line-height: 1.55;
  font-family: "JetBrains Mono", "SFMono-Regular", Consolas, monospace;
  font-size: 0.88rem;
}

.markdown-body {
  padding: 20px;
  line-height: 1.7;
}

.markdown-body > :first-child {
  margin-top: 0;
}

.markdown-body > :last-child {
  margin-bottom: 0;
}

.markdown-body h1,
.markdown-body h2,
.markdown-body h3 {
  line-height: 1.25;
}

.markdown-body h1 {
  padding-bottom: 0.35em;
  border-bottom: 1px solid var(--border);
  font-size: 2rem;
}

.markdown-body h2 {
  margin-top: 1.7em;
  padding-bottom: 0.25em;
  border-bottom: 1px solid var(--border);
  font-size: 1.45rem;
}

.markdown-body a {
  color: var(--accent-strong);
}

.markdown-body blockquote {
  margin-inline: 0;
  padding: 0.1rem 1rem;
  border-left: 4px solid var(--accent);
  color: var(--muted);
  background: color-mix(in srgb, var(--accent), transparent 92%);
}

.markdown-body code:not(pre code) {
  border-radius: 6px;
  background: var(--surface-alt);
  padding: 0.1em 0.35em;
  font-size: 0.88em;
}

.markdown-body pre {
  overflow: auto;
  border-radius: 8px;
  background: var(--code-bg);
  padding: 14px;
}

.markdown-body pre code {
  background: transparent;
  padding: 0;
}

.markdown-body table {
  display: block;
  width: 100%;
  border-spacing: 0;
  border-collapse: collapse;
  overflow: auto;
}

.markdown-body th,
.markdown-body td {
  border: 1px solid var(--border);
  padding: 8px 10px;
}

.markdown-body th {
  background: var(--surface-alt);
}

.markdown-body img {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
}

.markdown-body hr {
  border: 0;
  border-top: 1px solid var(--border);
}

@media (max-width: 860px) {
  .app-header {
    align-items: stretch;
    flex-direction: column;
  }

  .toolbar {
    justify-content: flex-start;
  }

  .workspace {
    min-height: 0;
    grid-template-columns: 1fr;
    grid-template-rows: minmax(0, 1fr) minmax(0, 1fr);
  }

  .pane {
    min-height: 0;
  }
}

@media print {
  html,
  body {
    height: auto;
    overflow: visible;
    background: #fff;
  }

  .app-header,
  .editor-pane,
  .pane-head {
    display: none;
  }

  .workspace,
  .pane,
  .markdown-body {
    display: block;
    height: auto;
    padding: 0;
    border: 0;
    box-shadow: none;
    overflow: visible;
  }
}