/* styles.css – Light green theme + dark VS Code code area with always-visible line numbers */
:root {
  --bg: #edf5ed;
  --panel: #f6faf6;
  --panel-alt: #edf5ed;
  --border: #c8dcc8;
  --text: #1a2e1a;
  --muted: #4a6a4a;
  --muted-2: #7a9a7a;
  --green: #3a8a5a;
  --green-bg: #3a8a5a12;
  --green-bg-2: #3a8a5a1f;
  --blue: #4a8aaa;
  --blue-bg: #4a8aaa12;
  --orange: #b0784a;
  --orange-bg: #b0784a22;
  --purple: #8a7aaa;
  --purple-bg: #8a7aaa12;
  --red: #b05a5a;
  --red-bg: #b05a5a12;
  --yellow: #a0904a;
  --yellow-bg: #a0904a1f;
  --radius: 10px;
  --mono: "JetBrains Mono", ui-monospace, "SF Mono", Consolas, "Liberation Mono", Menlo, monospace;
  --sans: "Plus Jakarta Sans", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;

  /* VS Code dark theme colors for code area */
  --vscode-bg: #1e1e2e;
  --vscode-panel: #181825;
  --vscode-border: #313244;
  --vscode-text: #cdd6f4;
  --vscode-muted: #6c7086;
  --vscode-green: #a6e3a1;
  --vscode-blue: #89b4fa;
  --vscode-orange: #fab387;
  --vscode-purple: #cba6f7;
  --vscode-red: #f38ba8;
  --vscode-yellow: #f9e2af;
  --vscode-cyan: #94e2d5;
  --vscode-pink: #f5c2e7;
  --vscode-line-highlight: #31324455;
  --vscode-selection: #585b7055;
  --vscode-line-number: #6c7086;
  --vscode-active-line-number: #a6e3a1;
  --vscode-gutter-border: #313244;
}

* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
button { font-family: inherit; }
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-thumb { background: #b8d0b8; border-radius: 6px; }
::-webkit-scrollbar-thumb:hover { background: #a0c0a0; }

/* ---------- Header ---------- */
header {
  height: 48px; flex: 0 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 16px; border-bottom: 1px solid var(--border);
  background: var(--panel);
}
.brand { display: flex; align-items: center; gap: 10px; }
.brand .logo {
  width: 26px; height: 26px; border-radius: 7px;
  background: linear-gradient(135deg, var(--green), #5aaa7a);
  display: flex; align-items: center; justify-content: center;
  color: #fff; font-weight: 800; font-size: 13px; font-family: var(--mono);
}
.brand h1 { font-size: 14px; font-weight: 800; letter-spacing: -.01em; margin: 0; }
.brand h1 span { color: var(--green); }
.divider { width: 1px; height: 20px; background: var(--border); margin: 0 4px; }
select#exampleSelect {
  height: 28px; font-size: 12px; border: 1px solid var(--border); border-radius: 7px;
  background: var(--panel); color: var(--text); padding: 0 8px; max-width: 220px;
}
.header-right { display: flex; align-items: center; gap: 8px; }
.hint { font-size: 11px; color: var(--muted-2); display: none; }
@media (min-width: 700px) { .hint { display: inline; } }
.icon-btn {
  width: 26px; height: 26px; border-radius: 7px; border: 1px solid transparent; background: transparent;
  display: flex; align-items: center; justify-content: center; cursor: pointer; color: var(--muted);
}
.icon-btn:hover { background: var(--panel-alt); color: var(--text); border-color: var(--border); }

/* ---------- Layout ---------- */
main { flex: 1; min-height: 0; display: flex; }
.col-left {
  flex: 1 1 56%; min-width: 0; display: flex; flex-direction: column; border-right: 1px solid var(--border);
}
.col-right {
  flex: 1 1 44%; min-width: 0; display: flex; flex-direction: column; overflow: hidden; background: var(--panel-alt);
}

/* ---------- Code area – VS Code Dark Theme with always-visible line numbers ---------- */
.code-wrap {
  flex: 1 1 55%; min-height: 0; position: relative;
  background: var(--vscode-bg);
  overflow: hidden;
}

.editor-wrap {
  position: absolute;
  inset: 0;
  display: flex;
  background: var(--vscode-bg);
  overflow: hidden;
}
.editor-wrap.hidden { display: none; }

/* Line numbers gutter - always visible, in sync with editor scroll */
.code-gutter {
  flex: 0 0 auto;
  width: 46px;
  padding: 12px 0;
  background: var(--vscode-panel);
  border-right: 1px solid var(--vscode-gutter-border);
  overflow: hidden;
  user-select: none;
  z-index: 3;
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.6;
  text-align: right;
  color: var(--vscode-line-number);
  pointer-events: none;
}

.code-gutter .gutter-line {
  padding: 0 10px 0 0;
  height: 20.8px;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  font-size: 12px;
  font-feature-settings: "tnum";
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
  transition: color 0.2s;
}

.code-gutter .gutter-line.active-line {
  color: var(--vscode-active-line-number);
  font-weight: 700;
}

/* Code content area next to the gutter */
.code-content {
  position: relative;
  flex: 1 1 auto;
  min-width: 0;
  overflow: auto;
  background: var(--vscode-bg);
}

pre#codeHighlight {
  position: absolute; inset: 0; margin: 0; padding: 12px 14px;
  font-family: var(--mono); font-size: 13px; line-height: 1.6;
  color: var(--vscode-text);
  white-space: pre-wrap; word-wrap: break-word; overflow: hidden; pointer-events: none;
  tab-size: 4; box-sizing: border-box;
  background: transparent;
  min-height: 100%;
}
pre#codeHighlight code { font: inherit; }

textarea#codeInput {
  position: absolute; inset: 0; width: 100%; height: 100%; resize: none; border: 0; outline: none;
  padding: 12px 14px;
  font-family: var(--mono); font-size: 13px; line-height: 1.6;
  color: transparent; caret-color: var(--vscode-text);
  background: transparent; tab-size: 4; white-space: pre-wrap; word-wrap: break-word;
  box-sizing: border-box; z-index: 1;
  min-height: 100%;
}
textarea#codeInput::selection {
  background: var(--vscode-selection);
}
textarea#codeInput::-moz-selection {
  background: var(--vscode-selection);
}

#codeView {
  width: 100%; height: 100%; overflow: auto;
  font-family: var(--mono); font-size: 13px; line-height: 1.6;
  background: var(--vscode-bg); display: none;
  color: var(--vscode-text);
}
#codeView.active { display: block; }

.code-line {
  display: flex; padding: 0 14px; white-space: pre;
  background: var(--vscode-bg);
  min-height: 20.8px;
}
.code-line .ln {
  width: 36px; flex: 0 0 36px; text-align: right; padding-right: 10px;
  color: var(--vscode-muted); user-select: none; font-size: 12px;
  font-feature-settings: "tnum";
  font-variant-numeric: tabular-nums;
}
.code-line .src { flex: 1; color: var(--vscode-text); }
.code-line.current-line {
  background: var(--vscode-line-highlight);
  border-left: 3px solid var(--vscode-green);
}
.code-line.current-line .ln { color: var(--vscode-green); font-weight: 700; }
.code-line.next-line {
  background: #89b4fa22;
  border-left: 3px solid var(--vscode-blue);
}

/* VS Code syntax highlighting colors */
.kw { color: var(--vscode-purple); font-weight: 600; }
.ty { color: var(--vscode-blue); }
.str { color: var(--vscode-green); }
.num { color: var(--vscode-orange); }
.cm { color: var(--vscode-muted); font-style: italic; }
.fn { color: var(--vscode-yellow); }
.va { color: var(--vscode-pink); }
.op { color: var(--vscode-cyan); }
.pp { color: var(--vscode-red); }

/* ---------- Controls ---------- */
.controls {
  flex: 0 0 auto; display: flex; align-items: center; gap: 8px; padding: 8px 12px;
  border-top: 1px solid var(--border); background: var(--panel);
  flex-wrap: wrap;
}
.controls .sep { width: 1px; height: 22px; background: var(--border); }
.btn {
  display: inline-flex; align-items: center; gap: 6px; height: 30px; padding: 0 10px;
  border-radius: 7px; border: 1px solid var(--border); background: var(--panel);
  font-size: 12px; font-weight: 600; color: var(--text); cursor: pointer;
}
.btn:hover { background: var(--panel-alt); }
.btn:disabled { opacity: .4; cursor: not-allowed; }
.btn.icon-only { width: 30px; padding: 0; justify-content: center; }
.btn.primary { background: var(--green); border-color: var(--green); color: #fff; }
.btn.primary:hover { background: #2a7a4a; }
select#speedSelect { height: 30px; border-radius: 7px; border: 1px solid var(--border); background: var(--panel); font-size: 12px; padding: 0 6px; }
#stepLabel { font-size: 11px; color: var(--muted); font-family: var(--mono); white-space: nowrap; }
input#stepSlider { flex: 1; min-width: 60px; accent-color: var(--green); }

/* ---------- IO panels ---------- */
.io-wrap { flex: 0 0 30%; display: flex; border-top: 1px solid var(--border); min-height: 110px; }
.io-panel { flex: 1; display: flex; flex-direction: column; min-width: 0; }
.io-panel + .io-panel { border-left: 1px solid var(--border); }
.io-title {
  font-size: 10.5px; font-weight: 700; letter-spacing: .06em; text-transform: uppercase; color: var(--muted);
  padding: 6px 10px; border-bottom: 1px solid var(--border); background: var(--panel-alt);
}
textarea#stdinInput {
  flex: 1; border: 0; outline: none; resize: none; padding: 8px 10px; font-family: var(--mono);
  font-size: 12.5px; background: var(--panel); color: var(--text);
  overflow: auto;
  white-space: pre-wrap;
  word-wrap: break-word;
}
#outputView {
  flex: 1; overflow: auto; padding: 8px 10px; font-family: var(--mono); font-size: 12.5px;
  white-space: pre-wrap; background: var(--panel); color: var(--text);
  word-wrap: break-word;
  overflow-x: auto;
}
#outputView .placeholder { color: var(--muted-2); font-style: italic; }
.error-banner {
  background: var(--red-bg); color: var(--red); border-top: 1px solid #b05a5a33;
  font-family: var(--mono); font-size: 12px; padding: 8px 12px; display: none;
}
.error-banner.show { display: block; }

/* ---------- Right panel ---------- */
.right-scroll { 
  flex: 1; 
  overflow: auto; 
  padding: 14px;
  overflow-x: auto;
}
.empty-state {
  height: 100%; display: flex; align-items: center; justify-content: center; text-align: center;
  color: var(--muted-2); flex-direction: column; gap: 8px;
}
.empty-state svg { opacity: .4; }
.section { margin-bottom: 16px; }
.section-title {
  display: flex; align-items: center; gap: 8px; font-size: 11px; font-weight: 700; text-transform: uppercase;
  letter-spacing: .06em; color: var(--muted); margin-bottom: 8px;
}
.dot { width: 8px; height: 8px; border-radius: 50%; }
.dot.green { background: var(--green); }
.dot.blue { background: var(--blue); }
.dot.orange { background: var(--orange); }

.frame-card {
  border: 1px solid var(--border); border-radius: var(--radius); background: var(--panel); margin-bottom: 10px; overflow: hidden;
  overflow-x: auto;
}
.frame-card.top { border-color: #3a8a5a55; box-shadow: 0 0 0 1px #3a8a5a22; }
.frame-head {
  display: flex; align-items: center; justify-content: space-between; gap: 8px; padding: 7px 10px;
  background: var(--green-bg); border-bottom: 1px solid var(--border); font-family: var(--mono);
  font-size: 12.5px; font-weight: 700; color: var(--green);
}
.frame-head .fname { display: flex; align-items: center; gap: 6px; }
.pulse { width: 6px; height: 6px; border-radius: 50%; background: var(--green); }
table.vars { 
  width: 100%; 
  border-collapse: collapse; 
  font-family: var(--mono); 
  font-size: 12px;
  min-width: 200px;
}
table.vars td { padding: 5px 10px; border-top: 1px solid var(--border); vertical-align: top; }
table.vars tr:first-child td { border-top: none; }
.vname { color: var(--blue); font-weight: 600; }
.vname.ptr { color: var(--orange); }
.vtype { color: var(--muted-2); font-size: 11px; }
.vval { font-weight: 700; text-align: right; transition: background .3s; }
.vval.changed { background: var(--yellow-bg); border-radius: 4px; }
.novars { padding: 10px; color: var(--muted-2); font-size: 12px; font-style: italic; }

.array-block { margin-bottom: 12px; }
.array-label { font-family: var(--mono); font-size: 11.5px; color: var(--muted); margin-bottom: 5px; }
.array-label b { color: var(--blue); }
.array-cells { 
  display: flex; 
  flex-wrap: wrap; 
  gap: 4px;
  overflow-x: auto;
  padding-bottom: 4px;
}
.cell { display: flex; flex-direction: column; align-items: center; flex-shrink: 0; }
.cell .box {
  width: 38px; height: 32px; border: 1px solid var(--border); border-radius: 6px; background: var(--blue-bg);
  display: flex; align-items: center; justify-content: center; font-family: var(--mono); font-size: 12.5px; font-weight: 700;
  transition: background .3s, border-color .3s;
  min-width: 30px;
}
.cell.changed .box { background: var(--yellow-bg); border-color: #a0904a88; }
.cell.swap-cell .box { background: var(--purple-bg); border-color: #8a7aaa88; }
.cell .idx { font-size: 9.5px; color: var(--muted-2); margin-top: 2px; }
.array-block { position: relative; }
.array-block.has-swap-arrow { margin-top: 26px; }
.swap-arrow-layer { position: absolute; left: 0; top: -24px; overflow: visible; pointer-events: none; }
.swap-arrow-layer .swap-arc { fill: none; stroke: var(--purple); stroke-width: 2; stroke-linecap: round;
  stroke-dasharray: 4 3; animation: swapArcFlow .5s linear infinite; }
.swap-arrow-layer .swap-arrowhead { fill: var(--purple); }
@keyframes swapArcFlow { from { stroke-dashoffset: 14; } to { stroke-dashoffset: 0; } }
@keyframes swapPulse {
  0% { transform: scale(1); box-shadow: 0 0 0 0 rgba(138,122,170,.45); }
  40% { transform: scale(1.14); box-shadow: 0 0 0 5px rgba(138,122,170,.22); }
  100% { transform: scale(1); box-shadow: 0 0 0 0 rgba(138,122,170,0); }
}
.cell .box.swap-pulse { animation: swapPulse .6s ease; }

.output-line { font-family: var(--mono); font-size: 12px; color: var(--muted); white-space: pre-wrap; padding: 6px 10px; border-top: 1px dashed var(--border); }

/* ---------- Modal ---------- */
.modal-overlay {
  position: fixed; inset: 0; background: #00000055; display: none; align-items: center; justify-content: center; z-index: 50;
}
.modal-overlay.show { display: flex; }
.modal {
  width: 100%; max-width: 520px; max-height: 80vh; overflow: auto; background: var(--panel);
  border-radius: 14px; border: 1px solid var(--border); padding: 20px 22px; box-shadow: 0 20px 50px #00000022;
}
.modal h2 { font-size: 15px; margin: 0 0 14px; }
.modal h3 { font-size: 11px; text-transform: uppercase; letter-spacing: .06em; margin: 16px 0 8px; display: flex; align-items: center; gap: 6px; }
.modal ul { margin: 0; padding-left: 0; list-style: none; }
.modal li { display: flex; gap: 8px; font-size: 13px; padding: 3px 0; color: #333; }
.modal li:before { content: ""; width: 6px; height: 6px; border-radius: 50%; margin-top: 6px; flex: 0 0 auto; background: currentColor; }
.modal .close-x {
  position: absolute; top: 14px; right: 14px; border: none; background: transparent; cursor: pointer; color: var(--muted);
  width: 26px; height: 26px; border-radius: 7px;
}
.modal .close-x:hover { background: var(--panel-alt); }
.modal-wrap { position: relative; }

/* ---------- MOBILE / RESPONSIVE - FIXED OUTPUT SIZE ---------- */
@media (max-width: 860px) {
  main { 
    flex-direction: column; 
    overflow: hidden;
  }
  
  .col-left, .col-right { 
    flex: none; 
    border-right: none;
    height: auto;
    min-height: 0;
  }
  
  .col-left { 
    height: 45vh; 
    min-height: 300px;
    border-bottom: 1px solid var(--border);
    display: flex;
    flex-direction: column;
  }
  
  .col-right { 
    height: 45vh; 
    min-height: 300px;
    overflow: hidden;
  }
  
  .code-wrap { 
    flex: 1 1 auto; 
    min-height: 0;
    overflow: hidden;
  }
  
  .code-content {
    overflow: auto !important;
    -webkit-overflow-scrolling: touch;
  }
  
  .io-wrap { 
    flex: 0 0 120px; 
    min-height: 120px;
    overflow: hidden;
  }
  
  .io-panel {
    overflow: hidden;
  }
  
  textarea#stdinInput {
    overflow: auto !important;
    min-height: 60px;
    white-space: pre-wrap;
    word-wrap: break-word;
  }
  
  #outputView {
    overflow: auto !important;
    min-height: 60px;
    max-height: 100%;
    white-space: pre-wrap;
    word-wrap: break-word;
    overflow-x: auto !important;
    -webkit-overflow-scrolling: touch;
  }
  
  .right-scroll {
    overflow: auto !important;
    flex: 1;
    overflow-x: auto !important;
    -webkit-overflow-scrolling: touch;
  }
  
  .controls { 
    gap: 4px; 
    padding: 6px 8px;
    flex-shrink: 0;
  }
  
  .btn { height: 28px; font-size: 11px; padding: 0 8px; }
  .btn.icon-only { width: 28px; }
  .brand h1 { font-size: 13px; }
  select#exampleSelect { max-width: 140px; font-size: 11px; }
  .header-right .hint { display: none; }
  
  .code-gutter { width: 36px; }
  .code-gutter .gutter-line { font-size: 11px; height: 17.6px; padding: 0 8px 0 0; }
  
  /* Horizontal scroll for array cells on mobile */
  .array-cells {
    flex-wrap: nowrap;
    overflow-x: auto !important;
    -webkit-overflow-scrolling: touch;
    padding-bottom: 8px;
  }
  
  .frame-card {
    overflow-x: auto !important;
    -webkit-overflow-scrolling: touch;
  }
  
  table.vars {
    min-width: 250px;
  }
}

/* ---------- Struct values in variable table ---------- */
.vval.struct-val { font-weight: 600; text-align: right; font-size: 11px; color: var(--purple); white-space: nowrap; }
.vval.heap-val { color: var(--orange); }

/* ---------- Footer ---------- */
.site-footer {
  flex: 0 0 auto; display: flex; align-items: center; justify-content: center; gap: 18px;
  padding: 9px 16px; border-top: 1px solid var(--border); background: var(--panel);
  font-size: 12px; color: var(--muted); flex-wrap: wrap; font-family: var(--sans);
}
.site-footer a { color: var(--green); text-decoration: none; font-weight: 700; }
.site-footer a:hover { text-decoration: underline; }
.site-footer .heart { color: var(--red); }
.site-footer .gh-link { display: inline-flex; align-items: center; gap: 6px; color: var(--muted); font-weight: 600; }
.site-footer .gh-link:hover { color: var(--text); }

@media (max-width: 480px) {
  .site-footer { font-size: 10.5px; padding: 7px 10px; gap: 10px; }
}

@media (max-width: 480px) {
  header { flex-wrap: wrap; height: auto; padding: 6px 10px; gap: 4px; }
  .brand { gap: 6px; }
  .brand .logo { width: 22px; height: 22px; font-size: 11px; }
  .brand h1 { font-size: 12px; }
  .divider { display: none; }
  select#exampleSelect { max-width: 100px; font-size: 10px; height: 24px; }
  .header-right { gap: 4px; }
  .icon-btn { width: 22px; height: 22px; }
  
  .col-left { 
    height: 40vh; 
    min-height: 250px;
  }
  .col-right { 
    height: 40vh; 
    min-height: 250px;
  }
  
  .io-wrap { 
    flex: 0 0 100px;
    min-height: 100px;
  }
  
  textarea#stdinInput {
    min-height: 50px;
    font-size: 11px;
    padding: 6px 8px;
  }
  
  #outputView {
    min-height: 50px;
    font-size: 11px;
    padding: 6px 8px;
  }
  
  .controls { gap: 3px; padding: 4px 6px; }
  .btn { height: 24px; font-size: 10px; padding: 0 6px; }
  .btn.icon-only { width: 24px; }
  input#stepSlider { min-width: 40px; }
  #stepLabel { font-size: 10px; }
  select#speedSelect { height: 24px; font-size: 10px; }
  .frame-head { font-size: 11px; padding: 5px 8px; }
  table.vars td { padding: 4px 6px; font-size: 11px; }
  table.vars { min-width: 180px; }
  .cell .box { width: 30px; height: 26px; font-size: 11px; min-width: 26px; }
  .array-label { font-size: 10px; }
  .code-line { font-size: 12px; padding: 0 8px; }
  .code-line .ln { width: 28px; flex: 0 0 28px; padding-right: 6px; font-size: 10px; }
  textarea#codeInput, pre#codeHighlight { font-size: 12px; padding: 8px 10px; }
  .modal { padding: 14px 16px; max-width: 96%; }
  .code-gutter { width: 28px; }
  .code-gutter .gutter-line { font-size: 10px; height: 16px; padding: 0 6px 0 0; }
  
  .code-content {
    overflow: auto !important;
    -webkit-overflow-scrolling: touch;
  }
  
  .array-cells {
    flex-wrap: nowrap;
    overflow-x: auto !important;
    -webkit-overflow-scrolling: touch;
    gap: 3px;
  }
}

/* Extra small screens */
@media (max-width: 380px) {
  .col-left { height: 35vh; min-height: 200px; }
  .col-right { height: 35vh; min-height: 200px; }
  .io-wrap { flex: 0 0 80px; min-height: 80px; }
}