:root {
  --bg-primary: #1e1e1e;
  --bg-secondary: #252526;
  --bg-tertiary: #2d2d2d;
  --border: #3e3e42;
  --text-primary: #d4d4d4;
  --text-secondary: #858585;
  --accent: #007acc;
  --accent-hover: #1a8ad4;
  --success: #388a34;
  --error: #f44747;
  --warning: #cca700;
  --font-ui: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Cascadia Code', 'Fira Code', 'Consolas', monospace;
}

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

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

body {
  font-family: var(--font-ui);
  background: var(--bg-primary);
  color: var(--text-primary);
  display: flex;
  flex-direction: column;
}

/* Header */
header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 20px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.header-left {
  display: flex;
  align-items: baseline;
  gap: 12px;
}

header h1 {
  font-size: 16px;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.tagline {
  font-size: 12px;
  color: var(--text-secondary);
}

.github-link {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 13px;
  transition: color 0.15s;
}

.github-link:hover {
  color: var(--text-primary);
}

/* Toolbar */
.toolbar {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 6px 20px;
  background: var(--bg-tertiary);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.toolbar-label {
  font-size: 12px;
  color: var(--text-secondary);
}

.toolbar-sep {
  width: 1px;
  height: 20px;
  background: var(--border);
  flex-shrink: 0;
}

/* Mode toggle (Program / Compiler) */
.mode-toggle {
  display: flex;
  border: 1px solid var(--border);
  border-radius: 3px;
  overflow: hidden;
  flex-shrink: 0;
}

.mode-btn {
  background: var(--bg-secondary);
  color: var(--text-secondary);
  border: none;
  padding: 4px 12px;
  font-family: var(--font-ui);
  font-size: 12px;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
  white-space: nowrap;
}

.mode-btn:not(:last-child) {
  border-right: 1px solid var(--border);
}

.mode-btn:hover:not(.active) {
  color: var(--text-primary);
  background: var(--bg-tertiary);
}

.mode-btn.active {
  background: var(--accent);
  color: #fff;
}

/* Program / Compiler controls wrappers */
#program-controls,
#compiler-controls {
  display: flex;
  align-items: center;
  gap: 10px;
}

#compiler-controls.hidden {
  display: none;
}

/* Compiler mode indicator */
.compiler-mode-indicator {
  font-size: 11px;
  color: var(--text-secondary);
  font-family: var(--font-mono);
  white-space: nowrap;
  flex-shrink: 0;
}

.compiler-mode-indicator.custom {
  color: #4ec9b0;
}

#file-select, #compiler-file-select {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 1px solid var(--border);
  padding: 4px 10px;
  border-radius: 3px;
  font-family: var(--font-ui);
  font-size: 12px;
  cursor: pointer;
  outline: none;
}

#file-select:focus, #compiler-file-select:focus {
  border-color: var(--accent);
}

#run-btn, #build-compiler-btn {
  background: var(--accent);
  color: #fff;
  border: none;
  padding: 5px 14px;
  border-radius: 3px;
  font-family: var(--font-ui);
  font-size: 12px;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.15s, opacity 0.15s;
  white-space: nowrap;
}

#run-btn:hover:not(:disabled),
#build-compiler-btn:hover:not(:disabled) {
  background: var(--accent-hover);
}

#run-btn:disabled,
#build-compiler-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

#run-btn.success, #build-compiler-btn.success {
  background: var(--success);
}

#run-btn.error, #build-compiler-btn.error {
  background: var(--error);
}

#new-file-btn, #reset-source-btn {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 1px solid var(--border);
  padding: 4px 10px;
  border-radius: 3px;
  font-family: var(--font-ui);
  font-size: 12px;
  cursor: pointer;
  transition: border-color 0.15s, color 0.15s;
  white-space: nowrap;
}

#new-file-btn:hover, #reset-source-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

#delete-file-btn {
  display: none;
  background: transparent;
  color: var(--error);
  border: 1px solid var(--error);
  padding: 4px 10px;
  border-radius: 3px;
  font-family: var(--font-ui);
  font-size: 12px;
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
  white-space: nowrap;
}

#delete-file-btn:hover {
  background: var(--error);
  color: #fff;
}

.save-indicator {
  font-size: 11px;
  color: transparent;
  font-family: var(--font-mono);
  transition: color 0.2s;
}

.save-indicator.saved {
  color: var(--success);
}

.save-indicator.save-error {
  color: var(--error);
}

#status {
  font-size: 11px;
  color: var(--text-secondary);
  margin-left: auto;
  font-family: var(--font-mono);
}

/* Main layout */
main {
  flex: 1;
  display: flex;
  overflow: hidden;
  min-height: 0;
}

.editor-panel {
  flex: 0 0 60%;
  min-width: 200px;
  overflow: hidden;
}

.resize-handle {
  flex: 0 0 4px;
  background: var(--border);
  cursor: col-resize;
  transition: background 0.15s;
}

.resize-handle:hover,
.resize-handle.active {
  background: var(--accent);
}

.output-panel {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 200px;
  overflow: hidden;
}

/* Console wrapper (contains output + terminal input) */
.console-tab-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  min-height: 0;
}

/* Terminal input row (shown when program reads from stdin) */
.terminal-input-row {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 5px 16px 7px;
  background: var(--bg-primary);
  border-top: 1px solid var(--border);
  flex-shrink: 0;
}

.terminal-input-row.hidden {
  display: none;
}

.terminal-prompt {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--accent);
  user-select: none;
  flex-shrink: 0;
}

#terminal-input {
  flex: 1;
  background: transparent;
  border: none;
  color: var(--text-primary);
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.6;
  outline: none;
  caret-color: var(--text-primary);
}

/* Output */
.tab-content {
  flex: 1;
  overflow: auto;
  padding: 12px 16px;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.6;
  white-space: pre-wrap;
  word-break: break-all;
  background: var(--bg-primary);
}

.tab-content.hidden {
  display: none;
}

.output-error {
  color: var(--error);
}

.output-info {
  color: var(--text-secondary);
  font-style: italic;
}

.output-success {
  color: #4ec9b0;
}

/* Responsive */
@media (max-width: 768px) {
  .tagline { display: none; }

  /* Tighter header on mobile */
  header {
    padding: 8px 12px;
  }

  /* Toolbar: wrap to second line instead of overflowing off-screen */
  .toolbar {
    flex-wrap: wrap;
    gap: 6px;
    padding: 6px 12px;
  }

  /* Vertical separator doesn't make sense in a wrapping layout */
  .toolbar-sep {
    display: none;
  }

  /* Control groups: fill available line width, wrap buttons internally */
  #program-controls,
  #compiler-controls {
    flex: 1 1 auto;
    flex-wrap: wrap;
    row-gap: 4px;
  }

  main {
    flex-direction: column;
  }

  .editor-panel {
    /* No !important — JS inline style must be able to override for touch resize */
    flex: 0 0 50%;
    min-height: 150px;
    min-width: unset;
    border-right: none;
  }

  /* Taller resize handle: finger-sized touch target with pill affordance */
  .resize-handle {
    flex: 0 0 10px;
    cursor: row-resize;
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .resize-handle::after {
    content: '';
    display: block;
    width: 40px;
    height: 4px;
    border-radius: 2px;
    background: var(--text-secondary);
    opacity: 0.5;
    pointer-events: none;
  }

  .output-panel {
    flex: 1;
    min-height: 80px;
    min-width: unset;
  }
}

/* Extra-small phones */
@media (max-width: 480px) {
  .toolbar {
    padding: 6px 10px;
  }

  /* Show GitHub icon only — free up ~60px on 320px screens */
  .github-text {
    display: none;
  }
}

/* ── Debugger UI ── */

/* Debug button — same secondary style as #new-file-btn */
#debug-btn {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 1px solid var(--border);
  padding: 4px 10px;
  border-radius: 3px;
  font-family: var(--font-ui);
  font-size: 12px;
  cursor: pointer;
  transition: border-color 0.15s, color 0.15s;
  white-space: nowrap;
}

#debug-btn:hover:not(:disabled) {
  border-color: var(--warning);
  color: var(--warning);
}

#debug-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

/* Debug control strip — inline in toolbar, separated by a border */
#debug-controls {
  display: flex;
  align-items: center;
  gap: 6px;
  border-left: 1px solid var(--border);
  padding-left: 10px;
}

#debug-controls.hidden {
  display: none;
}

/* "Debug" label — same as .toolbar-label */
.debug-label {
  font-size: 11px;
  color: var(--text-secondary);
  font-weight: 500;
  white-space: nowrap;
}

/* Step Into / Step Over / Continue — secondary toolbar buttons */
#debug-step-into-btn,
#debug-step-over-btn,
#debug-continue-btn {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 1px solid var(--border);
  padding: 4px 10px;
  border-radius: 3px;
  font-family: var(--font-ui);
  font-size: 12px;
  cursor: pointer;
  transition: border-color 0.15s, color 0.15s;
  white-space: nowrap;
}

#debug-step-into-btn:hover,
#debug-step-over-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

#debug-continue-btn:hover {
  border-color: var(--success);
  color: #4ec9b0;
}

/* Stop — danger style matching #delete-file-btn */
#debug-stop-btn {
  background: transparent;
  color: var(--error);
  border: 1px solid var(--error);
  padding: 4px 10px;
  border-radius: 3px;
  font-family: var(--font-ui);
  font-size: 12px;
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
  white-space: nowrap;
}

#debug-stop-btn:hover {
  background: var(--error);
  color: #fff;
}

/* Debug status text */
.debug-status {
  font-size: 11px;
  color: var(--text-secondary);
  min-width: 60px;
  white-space: nowrap;
}

/* Monaco current-execution-line decoration */
.debug-current-line {
  background: rgba(0, 122, 204, 0.12);
  border-left: 2px solid var(--accent);
}

.debug-current-line-gutter {
  background: var(--accent);
  border-radius: 2px;
  width: 4px !important;
  margin-left: 2px;
}

/* Breakpoint dot in the glyph margin */
.debug-breakpoint-glyph {
  background: var(--error);
  border-radius: 50%;
  width: 12px !important;
  height: 12px !important;
  margin: 3px 2px;
  cursor: pointer;
}

/* Faint red tint on breakpointed lines */
.debug-breakpoint-line {
  background: rgba(244, 71, 71, 0.07);
}

/* Clickable cursor over the gutter in program mode */
.monaco-editor .margin-view-overlays > div:hover {
  cursor: pointer;
}