:root {
  --bg-url: url("../book-cover-bg.png");

  --panel: transparent;
  --border: #d7dce5;
  --text: white;
  --muted: #dce2ee;
  --button-text: #1e1e1e;
  --button-border: #b9c2d0;
  --button-hover: #c9a7ff;
  --button-hover-border: #c9a7ff;
  --button-corner-hover: white;

  --accent: #c9a7ff;
  --accent-text: purple;
  --accent-border: purple;
  --accent-hover: magenta;
  --accent-hover-border: white;
  --accent-hover-text: white;
  --danger: #dc2626;
  --disabled: #e5e7eb;
  --handle: #cbd5e1;
  --error: red !important;
  --alert: rgb(255, 0, 0);
  --warn: orange;
  --action: rgb(30, 196, 238);
  --info: #18d318;

  --editor-tab-size: 4;
  --editor-bg: #1e1e1e;
  --editor-border: #2c2c2c;
  --editor-text: #d4d4d4;
  --editor-font: 15px/1.5 Consolas, "Courier New", monospace;
  --editor-line-height: 1.5;
  --editor-line-numbers-width: 48px;
  --editor-line-numbers-color: rgba(107, 114, 128, 0.9);
  --editor-line-number-active-bg: rgba(255, 255, 255, 0.25);
  --editor-line-number-active-color: #e5e7eb;
  --editor-calc-width: calc(100% - var(--editor-line-numbers-width));
  --editor-padding: 16px 16px 32px 16px;
  --editor-find-replace-bar: rgba(15, 23, 42, 0.92);
  --editor-status-bar: rgb(85, 81, 84);

  --shell-bg: #0f172a;
  --shell-text: #e5e7eb;
  --shell-input: #111827;
  --shell-prompt: #93c5fd;
  --shell-border: var(--border);

  --min-editor-width: 480px;
  --min-shell-width: 240px;

  --control-padding: 4px 8px;
  --control-radius: 6px;

  --backdrop-blur: blur(10px);
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
}

body {
  color: var(--button-text);
  background-image: var(--bg-url);
  background-size: cover;
  background-attachment: fixed;
  backdrop-filter: var(--backdrop-blur);
}

.app-header {
  position: sticky;
  top: 0;
  display: flex;
  flex-direction: row;
  align-items: center;
  justify-content: space-between; 
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
  background: rgb(38, 3, 63);
}

.app-header nav {
  display: flex;
  gap: 12px;
}

.app-header nav a {
  color: var(--text);
  text-decoration: none;
  font-size: 14px;
  padding: 4px 8px;
  border-radius: var(--control-radius);
}

.app-header nav a:hover{
  animation: glow 0.5s infinite alternate;
  color: var(--accent);
}

.app-title {
  font-size: 22px;
  font-weight: 700;
  color: var(--text);
}

.app-subtitle {
  margin-top: 4px;
  font-size: 18px;
  color: var(--muted);
}

.app-subtitle a {
  color: var(--text);
  text-decoration: none;
  font-size: 10px;
  padding: 2px 4px;
  border-radius: var(--control-radius);
}

.app-subtitle a:hover{
  animation: glow 0.5s infinite alternate;
  color: var(--accent);
}

.workspace {
  display: flex;
  height: calc(100vh - 76px);
  overflow: hidden;
}

.frame-pane {
  min-width: 0;
  min-height: 0;
}

.editor-host {
  width: 60%;
  min-width: var(--min-editor-width);
}

.shell-host {
  width: 40%;
  min-width: var(--min-shell-width);
}

.host-frame {
  width: 100%;
  height: 100%;
  border: 0;
  background: transparent;
}

.resizer {
  width: 10px;
  flex: 0 0 10px;
  cursor: col-resize;
  user-select: none;
  background: linear-gradient(
    to right,
    transparent 0,
    transparent 3px,
    var(--handle) 3px,
    var(--handle) 7px,
    transparent 7px
  );
}

.page-pane {
  display: flex;
  flex-direction: column;
  height: 100vh;
  background: var(--panel);
}

.pane-header,
.editor-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 10px 12px;
  background: var(--panel);
  color: var(--text);
}

.pane-header {
  border-bottom: 1px solid var(--border);
}

.editor-footer {
  display: flex;
  align-items: start;
  border-top: 1px solid var(--border);
}

.pane-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--text);
}

.toolbar,
.control-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}

.toolbar fieldset {
  border-radius: 8px;
  padding: 4px;
}

.control {
  display: flex;
  align-items: center;
  gap: 4px;
  white-space: nowrap;
}

.corner-button {
  position: sticky;
  top: 0;
  left: 0;
  z-index: 4;
  padding: 1px;
  border: 1px solid var(--button-border);
  border-radius: 0;
  background: transparent;
  color: var(--text);
  opacity: 0.50;
  cursor: pointer;
}

.corner-button:hover {
  border: 1px solid var(--button-border);
  background: transparent;
  opacity: .75;
  transition: all 0.15s ease;
}

.corner-button.active:hover {
  opacity: 1;
  filter: brightness(1.1);
}

.corner-button.active {
  color: var(--text);
  background-color: transparent;
  border-color: var(--text);
  opacity: 1;
}

button,
input,
label {
  font-size: 13px;
}

input[type="text"] {
  padding: var(--control-padding);
  border: 1px solid var(--border);
  border-radius: var(--control-radius);
}

button {
  padding: var(--control-padding);
  border: 1px solid var(--border);
  border-radius: var(--control-radius);
  background: white;
  color: var(--button-text);
  cursor: pointer;
  border-color: var(--button-border);
}

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

button.primary {
  color: var(--accent-text);
  background: var(--accent);
  border-color: var(--accent-border);
}

button.primary:hover {
  color: var(--accent-hover-text);
  border-color: var(--accent-hover-border);
}

button.danger {
  color: var(--danger);
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.55;
  border-color: var(--disabled);
}

button.active {
  background: var(--accent);
  border-color: var(--accent-border);
}

button.active:hover {
  filter: brightness(1.1);
}

.hidden {
  display: none !important;
}

.normal {
  opacity: 1;
  animation: none;
}

.pulse {
  opacity: 1;
  animation: glow 1s infinite alternate;
}

@keyframes glow {
  from {
    opacity: 0.75;
    box-shadow: 0 0 10px;
  }
  to {
    opacity: 1;
    box-shadow: 0 0 40px;
  }
}