:root{
  --bg: #f4f6f8;
  --nav: #1a2b3c;
  --nav-text: #e9edf1;
  --panel: #ffffff;
  --panel-border: #dfe4e8;
  --editor-bg: #ffffff;
  --editor-text: #2b2f33;
  --gutter-bg: #f7f8fa;
  --gutter-text: #a8b0b8;
  --console-bg: #1e1e1e;
  --console-text: #d4d4d4;
  --console-err: #f27967;
  --console-echo: #6a9955;
  --console-sys: #808080;
  --accent: #2fb170;
  --accent-dark: #24935c;
  --accent-soft: #e6f6ee;
  --muted: #6b7480;
  --radius: 6px;
  --topbar-h: 56px;
}
:root[data-theme="dark"]{
  --bg: #14181d;
  --nav: #0e1318;
  --nav-text: #e9edf1;
  --panel: #1b2126;
  --panel-border: #2c343b;
  --editor-bg: #1b2126;
  --editor-text: #dde3e8;
  --gutter-bg: #171c21;
  --gutter-text: #565f68;
  --console-bg: #111417;
  --console-text: #d4d4d4;
  --console-err: #f27967;
  --console-echo: #6a9955;
  --console-sys: #808080;
  --accent: #2fb170;
  --accent-dark: #3fd189;
  --accent-soft: #1c3327;
  --muted: #8a94a0;
}
*{box-sizing:border-box;}
html,body{margin:0;padding:0;height:100%;}
body{
  background:var(--bg);
  color:var(--editor-text);
  font-family:'Inter','Segoe UI',sans-serif;
  display:flex;
  flex-direction:column;
  min-height:100vh;
  transition:background .2s, color .2s;
}

/* ---------- Top bar ---------- */
.topbar{
  height:var(--topbar-h);
  background:var(--nav);
  color:var(--nav-text);
  display:flex;
  align-items:center;
  justify-content:space-between;
  padding:0 20px;
  flex-shrink:0;
  gap:16px;
}
.topbar .brand{
  display:flex;
  align-items:baseline;
  gap:8px;
  font-family:'Spectral', serif;
  font-size:20px;
  font-weight:600;
}
.topbar .brand span{ color:var(--accent); }
.topbar .brand small{
  font-family:'JetBrains Mono', monospace;
  font-size:11px;
  font-weight:400;
  color:#9aa7b3;
  letter-spacing:.5px;
}
.topbar .status{
  font-size:12px;
  color:#aeb8c2;
  display:flex;
  align-items:center;
  gap:7px;
  font-family:'JetBrains Mono', monospace;
}
.topbar .status .dot{
  width:7px; height:7px; border-radius:50%;
  background:#6b7480;
  transition:background .3s;
}
.topbar .status.ready .dot{ background:var(--accent); }
.topbar .status.error .dot{ background:var(--console-err); }

.topbar-right{
  display:flex;
  align-items:center;
  gap:10px;
}

.run-btn{
  background:var(--accent);
  color:#08301e;
  border:none;
  border-radius:var(--radius);
  padding:9px 22px;
  font-family:'JetBrains Mono', monospace;
  font-size:13px;
  font-weight:700;
  cursor:pointer;
  display:flex;
  align-items:center;
  gap:7px;
  transition:background .15s, transform .1s;
}
.run-btn:hover:not(:disabled){ background:#3fd189; }
.run-btn:active:not(:disabled){ transform:scale(0.97); }
.run-btn:disabled{ opacity:0.45; cursor:not-allowed; }
.run-btn svg{ width:12px; height:12px; }

.theme-btn{
  background:transparent;
  color:var(--nav-text);
  border:1px solid rgba(255,255,255,0.18);
  border-radius:var(--radius);
  width:34px;
  height:34px;
  display:flex;
  align-items:center;
  justify-content:center;
  cursor:pointer;
  flex-shrink:0;
  transition:background .15s, border-color .15s;
}
.theme-btn:hover{ background:rgba(255,255,255,0.08); border-color:rgba(255,255,255,0.32); }
.theme-btn svg{ width:16px; height:16px; }
.theme-btn .icon-sun{ display:none; }
:root[data-theme="dark"] .theme-btn .icon-moon{ display:none; }
:root[data-theme="dark"] .theme-btn .icon-sun{ display:block; }

/* ---------- Layout: editor left / console right ---------- */
.workspace{
  flex:1;
  display:flex;
  min-height:0;
  padding:14px;
  gap:14px;
}

.pane{
  flex:1;
  min-width:0;
  display:flex;
  flex-direction:column;
  background:var(--panel);
  border:1px solid var(--panel-border);
  border-radius:var(--radius);
  overflow:hidden;
  box-shadow:0 1px 2px rgba(20,30,40,0.04);
  transition:background .2s, border-color .2s;
}

.pane-header{
  padding:9px 14px;
  font-size:11.5px;
  font-weight:600;
  letter-spacing:.4px;
  text-transform:uppercase;
  color:var(--muted);
  border-bottom:1px solid var(--panel-border);
  display:flex;
  align-items:center;
  justify-content:space-between;
  background:#fafbfc;
  flex-shrink:0;
}
.pane-header .action{
  font-size:11px;
  font-weight:500;
  text-transform:none;
  color:var(--muted);
  cursor:pointer;
  letter-spacing:0;
}
.pane-header .action:hover{ color:var(--editor-text); }

/* ---------- Editor pane ---------- */
.editor-pane{ flex:1.15; }

.examples{
  display:flex;
  flex-wrap:wrap;
  gap:6px;
  padding:10px 14px 0;
  flex-shrink:0;
}
.chip{
  font-family:'JetBrains Mono', monospace;
  font-size:11px;
  color:var(--muted);
  background:#fff;
  border:1px solid var(--panel-border);
  border-radius:999px;
  padding:4px 12px;
  cursor:pointer;
  transition:border-color .15s, color .15s, background .15s;
}
.chip:hover{ border-color:var(--accent); color:var(--accent-dark); background:var(--accent-soft); }

.editor-body{
  flex:1;
  display:flex;
  min-height:0;
  margin-top:10px;
  font-family:'JetBrains Mono', monospace;
  font-size:13.5px;
  line-height:1.65;
}
.gutter{
  background:var(--gutter-bg);
  color:var(--gutter-text);
  text-align:right;
  padding:12px 10px 12px 0;
  user-select:none;
  white-space:pre;
  overflow:hidden;
  border-right:1px solid var(--panel-border);
  min-width:38px;
}
.editor-container {
  position: relative;
  flex: 1;
  min-height: 0;
  background: var(--editor-bg);
}
#highlight-backdrop {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  margin: 0;
  padding: 12px 14px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 13.5px;
  line-height: 1.65;
  white-space: pre-wrap;
  word-wrap: break-word;
  pointer-events: none;
  overflow: hidden;
  box-sizing: border-box;
  background: transparent;
  color: var(--editor-text);
  border: none;
}
#code-input {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  margin: 0;
  padding: 12px 14px;
  width: 100%;
  height: 100%;
  background: transparent;
  color: transparent;
  caret-color: var(--editor-text);
  overflow: auto;
  box-sizing: border-box;
  font-family: 'JetBrains Mono', monospace;
  font-size: 13.5px;
  line-height: 1.65;
  border: none;
  outline: none;
  resize: none;
  tab-size: 4;
}
#code-input::placeholder { color: #b7bfc6; }
#code-input:disabled { background: var(--bg); }

/* Syntax Highlighting Colors */
.hl-comment {
  color: #6a9955;
  font-style: italic;
}
.hl-string {
  color: #ce9178;
}
.hl-keyword {
  color: #569cd6;
  font-weight: bold;
}
.hl-constant {
  color: #b5cea8;
}
.hl-builtin {
  color: #4ec9b0;
}
.hl-number {
  color: #b5cea8;
}

/* Custom dark vs light colors */
:root[data-theme="light"] .hl-keyword { color: #0000ff; }
:root[data-theme="light"] .hl-string { color: #a31515; }
:root[data-theme="light"] .hl-comment { color: #008000; }
:root[data-theme="light"] .hl-builtin { color: #0451a5; }
:root[data-theme="light"] .hl-constant { color: #098658; }
:root[data-theme="light"] .hl-number { color: #098658; }

/* ---------- Console pane ---------- */
.console-pane{ flex:1; }
#output{
  flex:1;
  background:var(--console-bg);
  color:var(--console-text);
  padding:14px 16px;
  overflow-y:auto;
  font-family:'JetBrains Mono', monospace;
  font-size:13px;
  line-height:1.7;
  white-space:pre-wrap;
  word-break:break-word;
}
#output .line-out{ color:var(--console-text); }
#output .line-err{ color:var(--console-err); }
#output .line-echo{ color:var(--console-echo); }
#output .line-sys{ color:var(--console-sys); font-style:italic; }

/* ---------- Interactive stdin bar ---------- */
.console-pane {
  display: flex;
  flex-direction: column;
}
#output {
  flex: 1;
  min-height: 0;
}
.stdin-bar {
  display: flex;
  align-items: center;
  gap: 0;
  background: var(--console-bg);
  border-top: 1px solid rgba(255,255,255,0.08);
  padding: 6px 10px;
  flex-shrink: 0;
}
.stdin-prompt {
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px;
  color: var(--console-echo);
  white-space: pre;
  flex-shrink: 0;
  max-width: 200px;
  overflow: hidden;
  text-overflow: ellipsis;
}
.stdin-input {
  flex: 1;
  background: rgba(255,255,255,0.06);
  color: var(--console-text);
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: 4px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px;
  padding: 5px 10px;
  outline: none;
  min-width: 0;
}
.stdin-input:focus {
  border-color: var(--accent);
  background: rgba(255,255,255,0.09);
}
.stdin-send {
  background: var(--accent);
  color: #08301e;
  border: none;
  border-radius: 4px;
  margin-left: 8px;
  padding: 5px 14px;
  font-size: 15px;
  cursor: pointer;
  font-family: 'JetBrains Mono', monospace;
  font-weight: 700;
  transition: background .15s;
  flex-shrink: 0;
}
.stdin-send:hover { background: #3fd189; }

footer{
  text-align:center;
  padding:9px 20px 16px;
  font-size:11px;
  color:var(--muted);
  flex-shrink:0;
}

@media (max-width:840px){
  .workspace{ flex-direction:column; }
  .pane{ min-height:280px; }
  .topbar .brand small{ display:none; }
}