@import url('https://fonts.googleapis.com/css2?family=DM+Sans:opsz,wght@9..40,400;9..40,500&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
  --bg:        #0f0f0f;
  --surface:   #0f0f0f;
  --border:    #1e1e1e;
  --text:      #d4d4d4;
  --muted:     #4a4a4a;
  --accent:    #a8ff78;
  --error:     #f87171;
  --comment:   #3a3a3a;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', 'Menlo', monospace;
  --font-ui:   'DM Sans', system-ui, -apple-system, sans-serif;
}

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

html, body {
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-ui);
  font-size: 13px;
  line-height: 1.5;
  overflow: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ── Header ──────────────────────────────────────────────────────────────── */

header {
  display: flex;
  align-items: center;
  gap: 0.625rem;
  padding: 0 1rem;
  height: 40px;
  border-bottom: 1px solid var(--border);
  background: var(--bg);
  flex-shrink: 0;
  position: relative;
  z-index: 10;
}

.back-link {
  color: var(--muted);
  text-decoration: none;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  line-height: 1;
  padding: 2px 4px;
  transition: color 0.1s;
}
.back-link:hover { color: var(--text); }

.logo {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text);
  letter-spacing: 0.04em;
}

.header-right {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 1rem;
}

.examples-select {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  padding: 3px 6px;
  border-radius: 2px;
  cursor: pointer;
  outline: none;
  appearance: none;
  -webkit-appearance: none;
}
.examples-select:hover { color: var(--text); border-color: #333; }
.examples-select option { background: #1a1a1a; color: var(--text); }

.gh-link {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--muted);
  text-decoration: none;
}
.gh-link:hover { color: var(--text); }

/* ── Layout ──────────────────────────────────────────────────────────────── */

main {
  display: flex;
  height: calc(100vh - 40px - 22px);
  overflow: hidden;
}

.divider {
  width: 1px;
  background: var(--border);
  flex-shrink: 0;
}

/* ── Editor pane ─────────────────────────────────────────────────────────── */

#editor-pane {
  flex: 1;
  min-width: 0;
  overflow: hidden;
  position: relative;
}

/* CodeMirror — force dark background, override CDN defaults */
.CodeMirror {
  height: 100% !important;
  background: var(--bg) !important;
  color: var(--text) !important;
  font-family: var(--font-mono) !important;
  font-size: 13px !important;
  line-height: 1.75 !important;
  padding: 0.75rem 0;
}

.CodeMirror-scroll { padding-bottom: 40px; }

.CodeMirror-gutters {
  background: var(--bg) !important;
  border-right: 1px solid var(--border) !important;
}

.CodeMirror-linenumber {
  color: var(--muted) !important;
  padding: 0 10px 0 6px;
}

.CodeMirror-cursor { border-left: 1px solid var(--text) !important; }
.CodeMirror-selected { background: rgba(255,255,255,0.05) !important; }
.CodeMirror-focused .CodeMirror-selected { background: rgba(255,255,255,0.06) !important; }
.CodeMirror-activeline-background { background: rgba(255,255,255,0.02) !important; }

/* Syntax tokens */
.cm-keyword  { color: #c792ea !important; }
.cm-def      { color: var(--text) !important; }
.cm-variable { color: var(--text) !important; }
.cm-number   { color: #f78c6c !important; }
.cm-string   { color: #c3e88d !important; }
.cm-comment  { color: var(--comment) !important; font-style: italic; }
.cm-builtin  { color: #82aaff !important; }
.cm-operator { color: var(--muted) !important; }

/* ── Output pane ─────────────────────────────────────────────────────────── */

#output-pane {
  flex: 1;
  min-width: 0;
  overflow-y: auto;
  padding: 0.75rem 0;
  background: var(--bg);
}

#output {
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.75;
  white-space: pre;
  padding: 0 1.25rem;
}

.line-ok      { color: var(--accent); opacity: 0.75; }
.line-err     { color: var(--error); }
.line-empty   { color: transparent; user-select: none; display: block; }
.line-comment { color: var(--comment); }

/* ── Status bar ──────────────────────────────────────────────────────────── */

#status {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: 22px;
  background: var(--bg);
  border-top: 1px solid var(--border);
  display: flex;
  align-items: center;
  padding: 0 1rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--muted);
  gap: 1.25rem;
  z-index: 10;
}
#status .ok   { color: var(--accent); opacity: 0.85; }
#status .fail { color: var(--error); }

/* ── Scrollbar ───────────────────────────────────────────────────────────── */

::-webkit-scrollbar { width: 5px; height: 5px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: #222; border-radius: 2px; }
::-webkit-scrollbar-thumb:hover { background: #333; }