/* 🧬 FASTA Regex Editor - TATAbox Aesthetic V2 */

:root {
  --bg: #0f172a;
  --card: #1e293b;
  --text: #f8fafc;
  --muted: #94a3b8;
  --accent: #0ea5e9;
  --accent-hov: #38bdf8;
  --border: #334155;
  --success: #10b981;
  --error: #ef4444;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Roboto Mono', monospace;
  --radius: 0.4rem;
}

body.light {
  --bg: #f8fafc;
  --card: #ffffff;
  --text: #0f172a;
  --muted: #64748b;
  --border: #e2e8f0;
  --accent: #0284c7;
}

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

html, body {
  min-height: 100vh;
  font-family: var(--font-mono);
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
  font-size: 1.05rem;
  overflow-x: hidden;
}

/* Header */
.top-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  border-bottom: 1px solid var(--border);
  background: rgba(15, 23, 42, 0.9);
  backdrop-filter: blur(12px);
  position: sticky;
  top: 0;
  z-index: 100;
}

.brand {
  color: var(--accent);
  font-weight: bold;
  font-size: 1.1rem;
  letter-spacing: -0.5px;
}

.nav-actions { display: flex; gap: 0.5rem; }

/* Main Workspace */
.workspace {
  max-width: 1600px;
  margin: 0 auto;
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

/* Mode Selector Area */
.toolbar {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  align-items: center;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border);
}

.mode-switcher {
  display: flex;
  background: rgba(0,0,0,0.2);
  padding: 0.3rem;
  border-radius: var(--radius);
  border: 1px solid var(--border);
}

.mode-btn {
  background: transparent;
  color: var(--muted);
  border: none;
  padding: 0.5rem 1.5rem;
  cursor: pointer;
  border-radius: calc(var(--radius) - 2px);
  font-size: 0.8rem;
  text-transform: uppercase;
  transition: all 0.2s;
}

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

/* Central Controls */
.control-panel {
  width: 100%;
  max-width: 800px;
  margin: 0 auto;
  display: none; /* Controlled by JS */
}

.control-panel.active { display: block; }

.helper-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: 1rem;
}

.chip {
  background: var(--border);
  color: var(--text);
  padding: 0.2rem 0.6rem;
  border-radius: 4px;
  font-size: 0.75rem;
  cursor: pointer;
  border: 1px solid transparent;
}

.chip:hover { border-color: var(--accent); color: var(--accent); }

/* Input/Output Comparison */
.comparison-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
  min-height: 500px;
}

@media (min-width: 1024px) {
  .comparison-grid { grid-template-columns: 1fr 1fr; }
}

.pane {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  display: flex;
  flex-direction: column;
  height: 100%;
}

.pane-header {
  padding: 0.6rem 1rem;
  background: rgba(0,0,0,0.1);
  border-bottom: 1px solid var(--border);
  font-size: 0.8rem;
  color: var(--accent);
}

.pane-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  padding: 1rem;
}

textarea {
  flex: 1;
  width: 100%;
  background: transparent;
  border: none;
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 0.9rem;
  resize: none;
  outline: none;
  min-height: 300px;
}

select {
  background: var(--bg) !important;
  color: var(--text) !important;
  border: 1px solid var(--border);
  padding: 0.6rem;
  border-radius: var(--radius);
  width: 100%;
  font-family: var(--font-mono);
}

input[type=text] {
  width: 100%;
  padding: 0.8rem;
  background: rgba(0,0,0,0.2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-family: var(--font-mono);
  margin-bottom: 0.5rem;
}

input:focus { border-color: var(--accent); outline: none; }

.preview-box {
  flex: 1;
  background: rgba(0,0,0,0.1);
  overflow-y: auto;
  padding: 0.5rem;
  font-size: 0.85rem;
}

/* Diff Styling */
.diff-line { padding: 2px 4px; border-radius: 2px; margin-bottom: 2px; }
.diff-old { background: rgba(239, 68, 68, 0.15); color: #fca5a5; text-decoration: line-through; }
.diff-new { background: rgba(16, 185, 129, 0.15); color: #6ee7b7; }

/* Final Actions */
.footer-actions {
  display: flex;
  justify-content: center;
  padding: 1rem;
  gap: 1rem;
}

button.primary {
  background: var(--accent);
  color: white;
  padding: 0.8rem 2rem;
  border-radius: var(--radius);
  border: none;
  cursor: pointer;
  font-weight: bold;
  text-transform: uppercase;
  letter-spacing: 1px;
}

button.primary:hover { background: var(--accent-hov); }

.hidden { display: none; }
#regex-error { color: var(--error); font-size: 0.7rem; margin-bottom: 0.5rem; display: block; }