/* ═══════════════════════════════════════════════════════
   RE Lab — style.css  v2
   Dark : Deep Violet × Electric Indigo × Neon Cyan
   Light: Crisp White × Vivid Purple × Clean Slate
   Fonts: IBM Plex Mono + Plus Jakarta Sans
═══════════════════════════════════════════════════════ */

@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Mono:wght@300;400;500;600;700&family=Plus+Jakarta+Sans:wght@400;500;600;700;800&display=swap');

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

@keyframes logoPulse {
  0% { transform: scale(1); box-shadow: 0 0 15px rgba(34,212,253,0.3); }
  50% { transform: scale(1.05); box-shadow: 0 0 35px rgba(34,212,253,0.6); }
  100% { transform: scale(1); box-shadow: 0 0 15px rgba(34,212,253,0.3); }
}

/* ── Dark theme (default) ── */
:root {
  --bg:          #0f0e17;
  --bg2:         #16152a;
  --bg3:         #1e1d35;
  --bg4:         #262548;
  --bg5:         #302f56;
  --border:      #2a2850;
  --border2:     #3d3b70;
  --border3:     #5450a0;
  --text:        #eeeaf8;
  --text2:       #9d98c8;
  --text3:       #5c5890;
  --accent:      #7c6dff;
  --accent2:     #9d8fff;
  --accent3:     #bdb2ff;
  --accent-dim:  rgba(124,109,255,0.12);
  --accent-glow: rgba(124,109,255,0.25);
  --cyan:        #22d4fd;
  --cyan-dim:    rgba(34,212,253,0.1);
  --green:       #2affc8;
  --green-bg:    #041a14;
  --green-bdr:   #0d5040;
  --red:         #ff5a7e;
  --red-bg:      #1a0410;
  --red-bdr:     #580a28;
  --amber:       #ffc23a;
  --amber-bg:    #1a1000;
  --header-bg:   rgba(15,14,23,0.92);
  --header-bdr:  rgba(124,109,255,0.22);
  --shadow:      rgba(0,0,0,0.5);
  --shadow2:     rgba(124,109,255,0.15);
  --mono:        'IBM Plex Mono', monospace;
  --sans:        'Plus Jakarta Sans', sans-serif;
  --radius:      8px;
  --radius-lg:   12px;
  --radius-xl:   16px;
  --tr:          0.2s cubic-bezier(0.4,0,0.2,1);
}

/* ── Light theme ── */
[data-theme="light"] {
  --bg:          #f3f2ff;
  --bg2:         #ffffff;
  --bg3:         #eeecff;
  --bg4:         #e5e2ff;
  --bg5:         #d8d4ff;
  --border:      #dddaff;
  --border2:     #c9c3ff;
  --border3:     #a89aff;
  --text:        #18162e;
  --text2:       #48437a;
  --text3:       #8c86b8;
  --accent:      #5a46f5;
  --accent2:     #7260f8;
  --accent3:     #9080ff;
  --accent-dim:  rgba(90,70,245,0.08);
  --accent-glow: rgba(90,70,245,0.2);
  --cyan:        #0098d4;
  --cyan-dim:    rgba(0,152,212,0.08);
  --green:       #00a86b;
  --green-bg:    #e6fff5;
  --green-bdr:   #9fe8cf;
  --red:         #e8174e;
  --red-bg:      #fff0f4;
  --red-bdr:     #ffb3c8;
  --amber:       #c47a00;
  --amber-bg:    #fff8e6;
  --header-bg:   rgba(255,255,255,0.94);
  --header-bdr:  rgba(90,70,245,0.15);
  --shadow:      rgba(90,70,245,0.08);
  --shadow2:     rgba(90,70,245,0.12);
}

/* ── Global theme transition ── */
html { transition: background var(--tr), color var(--tr); }
body, .site-header, .sidebar-card, .analysis-panel,
.gen-output, .batch-output, .pipe-step, .stat-card,
.re-input, .batch-textarea, .sym-btn, .snippet-btn,
.icon-btn, .example-menu, .equiv-result-box,
.string-pill, .batch-row, .equiv-check-row,
.ref-table td, .example-item, .theme-toggle {
  transition: background var(--tr), border-color var(--tr),
              color var(--tr), box-shadow var(--tr);
}

html { font-size: 16px; scroll-behavior: smooth; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  min-height: 100vh;
  line-height: 1.6;
}

/* ── Background mesh ── */
.bg-grid {
  position: fixed; inset: 0; z-index: 0; pointer-events: none;
  overflow: hidden;
}
.bg-grid::before {
  content: '';
  position: absolute; inset: 0;
  background:
    radial-gradient(ellipse 70% 50% at 15% 5%,  rgba(124,109,255,0.12) 0%, transparent 60%),
    radial-gradient(ellipse 50% 60% at 85% 90%, rgba(34,212,253,0.07)  0%, transparent 55%),
    radial-gradient(ellipse 40% 40% at 60% 40%, rgba(42,255,200,0.04)  0%, transparent 50%),
    radial-gradient(circle 500px at var(--mouse-x, 50%) var(--mouse-y, 50%), rgba(124,109,255,0.09), transparent 50%);
  transition: opacity 0.5s;
}
[data-theme="light"] .bg-grid::before {
  background:
    radial-gradient(ellipse 70% 50% at 15% 5%,  rgba(90,70,245,0.06)  0%, transparent 60%),
    radial-gradient(ellipse 50% 60% at 85% 90%, rgba(0,152,212,0.04)   0%, transparent 55%),
    radial-gradient(ellipse 40% 40% at 60% 40%, rgba(0,168,107,0.03)   0%, transparent 50%),
    radial-gradient(circle 500px at var(--mouse-x, 50%) var(--mouse-y, 50%), rgba(90,70,245,0.06), transparent 50%);
}
.bg-grid::after {
  content: '';
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(124,109,255,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(124,109,255,0.03) 1px, transparent 1px);
  background-size: 40px 40px;
}
[data-theme="light"] .bg-grid::after {
  background-image:
    linear-gradient(rgba(90,70,245,0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(90,70,245,0.04) 1px, transparent 1px);
}

/* ── Header ── */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: var(--header-bg);
  backdrop-filter: blur(24px) saturate(180%);
  border-bottom: 1px solid var(--header-bdr);
  box-shadow: 0 2px 24px var(--shadow);
}
.header-inner {
  max-width: 1280px; margin: 0 auto;
  padding: 0 2rem;
  display: flex; align-items: center; justify-content: space-between;
  height: 62px; gap: 1rem;
}

/* ── Logo ── */
.logo {
  font-family: var(--sans); font-size: 16px; font-weight: 800;
  color: var(--text); display: flex; align-items: center; gap: 10px;
  letter-spacing: -0.02em; flex-shrink: 0; text-decoration: none;
}
.logo-mark {
  width: 34px; height: 34px;
  background: linear-gradient(135deg, var(--accent), var(--cyan));
  border-radius: var(--radius);
  display: flex; align-items: center; justify-content: center;
  font-size: 11px; font-weight: 800; color: #fff;
  letter-spacing: 0.04em;
  box-shadow: 0 4px 16px var(--accent-glow);
  animation: logoPulse 3s ease-in-out infinite;
  flex-shrink: 0;
}
@keyframes logoPulse {
  0%,100% { box-shadow: 0 4px 16px var(--accent-glow); }
  50%     { box-shadow: 0 4px 28px var(--accent-glow), 0 0 0 4px var(--accent-dim); }
}
.logo-text { color: var(--text); }
.logo-sub {
  font-size: 11px; font-weight: 500; color: var(--text3);
  border-left: 1.5px solid var(--border2); padding-left: 10px;
}

/* ── Nav ── */
.main-nav { display: flex; gap: 2px; }
.nav-btn {
  padding: 8px 14px; border: none; background: transparent;
  color: var(--text3); font-family: var(--sans); font-size: 13px;
  font-weight: 600; border-radius: var(--radius); cursor: pointer;
  transition: color var(--tr), background var(--tr);
  position: relative;
}
.nav-btn:hover { color: var(--text2); background: var(--accent-dim); }
.nav-btn.active { color: var(--accent2); background: var(--accent-dim); }
.nav-btn.active::after {
  content: '';
  position: absolute; bottom: 4px; left: 50%; transform: translateX(-50%);
  width: 16px; height: 2.5px; border-radius: 2px;
  background: linear-gradient(90deg, var(--accent), var(--cyan));
}

/* ── Header right group ── */
.header-right { display: flex; align-items: center; gap: 10px; }

/* ── Theme Toggle ── */
.theme-toggle {
  width: 40px; height: 40px;
  display: flex; align-items: center; justify-content: center;
  border: 1.5px solid var(--border2); border-radius: var(--radius);
  background: var(--bg3); cursor: pointer;
  font-size: 17px; color: var(--text2); flex-shrink: 0;
  transition: all var(--tr);
}
.theme-toggle:hover {
  border-color: var(--accent); background: var(--accent-dim);
  color: var(--accent2);
  box-shadow: 0 0 16px var(--accent-dim);
  transform: rotate(18deg) scale(1.05);
}
.theme-toggle:active { transform: scale(0.92); }
.theme-toggle .icon-sun  { display: none; }
.theme-toggle .icon-moon { display: block; }
[data-theme="light"] .theme-toggle .icon-sun  { display: block; }
[data-theme="light"] .theme-toggle .icon-moon { display: none; }

/* ── Main layout ── */
.main-content {
  position: relative; z-index: 1;
  max-width: 1280px; margin: 0 auto;
  padding: 2.5rem 2rem 5rem;
}
.tab-section { display: none; }
.tab-section.active {
  display: block;
  animation: tabReveal 0.35s cubic-bezier(0.22,1,0.36,1);
}
@keyframes tabReveal {
  from { opacity: 0; transform: translateY(14px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ── Section hero ── */
.section-hero {
  margin-bottom: 2.5rem; padding-bottom: 2rem;
  border-bottom: 1px solid var(--border2);
  display: flex; align-items: flex-start; gap: 1.5rem;
}
.section-hero-num {
  font-family: var(--sans); font-size: 56px; font-weight: 800;
  line-height: 1; flex-shrink: 0; margin-top: -4px;
  letter-spacing: -0.04em; user-select: none;
  background: linear-gradient(135deg, var(--accent), var(--cyan));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text; opacity: 0.22;
}
.section-hero-body { flex: 1; }
.section-title {
  font-family: var(--sans); font-size: 30px; font-weight: 800;
  color: var(--text); letter-spacing: -0.025em; line-height: 1.15;
  margin-bottom: 8px;
}
.section-title span {
  background: linear-gradient(135deg, var(--accent2), var(--cyan));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
}
.section-desc { color: var(--text3); font-size: 14px; max-width: 580px; line-height: 1.7; }

/* ── Field labels ── */
.field-label {
  display: block; font-size: 11px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.1em;
  color: var(--text3); margin-bottom: 8px;
}
.field-hint { font-weight: 400; text-transform: none; letter-spacing: 0; }
.re-input-row { display: flex; gap: 8px; }
.re-field-wrap { margin-bottom: 0.5rem; }

/* ── RE Input ── */
.re-input {
  width: 100%; padding: 13px 18px;
  font-family: var(--mono); font-size: 19px; font-weight: 500;
  background: var(--bg2); border: 1.5px solid var(--border2);
  border-radius: var(--radius-lg); color: var(--text);
  outline: none; caret-color: var(--accent2); letter-spacing: 0.03em;
  transition: border-color var(--tr), box-shadow var(--tr), background var(--tr);
}
.re-input:focus {
  border-color: var(--accent); background: var(--bg3);
  box-shadow: 0 0 0 3px var(--accent-dim), 0 4px 20px var(--shadow);
}
.re-input.large { font-size: 21px; }
.re-input::placeholder { color: var(--text3); font-weight: 300; }

.icon-btn {
  padding: 0 16px; background: var(--bg3); border: 1.5px solid var(--border2);
  border-radius: var(--radius); color: var(--text2); cursor: pointer;
  font-size: 14px; font-family: var(--mono); white-space: nowrap;
  transition: all var(--tr);
}
.icon-btn:hover { border-color: var(--accent); color: var(--accent2); background: var(--accent-dim); }
.icon-btn:active { transform: scale(0.94); }

/* ── Palette ── */
.palette-section { display: flex; flex-wrap: wrap; gap: 20px; margin-top: 1.75rem; }
.palette-group { display: flex; flex-direction: column; gap: 10px; }
.palette-group-label {
  font-size: 10px; font-weight: 700; text-transform: uppercase;
  letter-spacing: 0.12em; color: var(--text3);
}
.palette-row { display: flex; gap: 6px; flex-wrap: wrap; }
.palette-row.wrap { flex-wrap: wrap; max-width: 620px; }

.sym-btn {
  padding: 9px 15px; font-family: var(--mono); font-size: 15px; font-weight: 500;
  background: var(--bg3); border: 1.5px solid var(--border2);
  border-radius: var(--radius); color: var(--text); cursor: pointer;
  transition: all var(--tr); min-width: 46px; text-align: center;
}
.sym-btn:hover {
  background: var(--bg4); border-color: var(--accent);
  transform: translateY(-3px);
  box-shadow: 0 6px 20px var(--shadow), 0 0 0 1px var(--accent-dim);
}
.sym-btn:active { transform: scale(0.9) translateY(0); transition-duration: 0.07s; }
.sym-btn.op { color: var(--accent2); border-color: rgba(124,109,255,0.3); background: var(--accent-dim); }
.sym-btn.op:hover { background: var(--bg4); border-color: var(--accent); color: var(--accent3); }

.snippet-btn {
  padding: 6px 14px; font-family: var(--mono); font-size: 12px; font-weight: 500;
  background: var(--bg3); border: 1.5px solid var(--border2);
  border-radius: 20px; color: var(--text3); cursor: pointer;
  transition: all var(--tr);
}
.snippet-btn:hover {
  border-color: var(--accent); color: var(--accent2); background: var(--accent-dim);
  box-shadow: 0 4px 14px var(--shadow2);
}
.snippet-btn.small { font-size: 11px; padding: 4px 11px; }

/* ── Analysis panel ── */
.analysis-panel {
  margin-top: 2rem; padding: 1.5rem 1.75rem;
  background: var(--bg2); border: 1.5px solid var(--border2);
  border-radius: var(--radius-xl); position: relative; overflow: hidden;
}
.analysis-panel::before {
  content: '';
  position: absolute; top: 0; left: 0; right: 0; height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--cyan), var(--green), var(--accent));
  background-size: 200% 100%;
  animation: gradientShift 4s linear infinite;
}
@keyframes gradientShift {
  0%   { background-position: 0% 0%; }
  100% { background-position: 200% 0%; }
}

.analysis-empty { color: var(--text3); font-size: 13px; font-family: var(--mono); font-style: italic; }
.analysis-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
  gap: 12px; margin-bottom: 1.25rem;
}
.stat-card {
  background: var(--bg3); border: 1.5px solid var(--border2);
  border-radius: var(--radius-lg); padding: 14px 18px; cursor: default;
}
.stat-card:hover {
  border-color: var(--accent); transform: translateY(-2px);
  box-shadow: 0 8px 24px var(--shadow2);
}
.stat-num {
  font-family: var(--mono); font-size: 32px; font-weight: 700; line-height: 1;
  background: linear-gradient(135deg, var(--accent2), var(--cyan));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
}
.stat-lbl { font-size: 10px; color: var(--text3); margin-top: 5px; text-transform: uppercase; letter-spacing: 0.1em; font-weight: 600; }
.analysis-row { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; margin-top: 10px; }
.analysis-tag {
  font-size: 12px; padding: 4px 12px; border-radius: 20px;
  background: var(--bg4); border: 1px solid var(--border2);
  color: var(--text2); font-family: var(--mono);
}
.analysis-tag.good { background: var(--green-bg); border-color: var(--green-bdr); color: var(--green); }
.analysis-tag.warn { background: var(--amber-bg); border-color: rgba(255,194,58,0.3); color: var(--amber); }
.analysis-error { color: var(--red); font-size: 13px; font-family: var(--mono); }

/* ── Builder layout ── */
.builder-layout { display: grid; grid-template-columns: 1fr 270px; gap: 2rem; align-items: start; }
.builder-sidebar { display: flex; flex-direction: column; gap: 1rem; }
.sidebar-card {
  background: var(--bg2); border: 1.5px solid var(--border2);
  border-radius: var(--radius-xl); padding: 1.25rem 1.5rem;
}
.sidebar-card:hover { border-color: var(--border3); }
.sidebar-card-title { font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.1em; color: var(--accent2); margin-bottom: 14px; }
.prec-list {
  padding-left: 0; color: var(--text2); font-size: 13px;
  display: flex; flex-direction: column; gap: 8px; list-style: none; counter-reset: prec;
}
.prec-list li {
  display: flex; align-items: center; gap: 10px; counter-increment: prec;
  padding: 7px 12px; border-radius: var(--radius);
  background: var(--bg3); border: 1px solid var(--border);
}
.prec-list li::before {
  content: counter(prec); font-size: 9px; font-weight: 800;
  color: var(--accent); width: 14px; flex-shrink: 0;
}
.prec-list code { font-family: var(--mono); color: var(--accent2); font-size: 12px; }

.identity-list { display: flex; flex-direction: column; gap: 4px; }
.identity { padding: 6px 10px; border-radius: var(--radius); transition: background var(--tr); }
.identity:hover { background: var(--bg3); }
.identity code { font-family: var(--mono); font-size: 12px; color: var(--text2); }

/* ── Generator ── */
.gen-layout { display: flex; flex-direction: column; gap: 1.5rem; }
.controls-row { display: flex; gap: 2rem; margin-top: 1.25rem; flex-wrap: wrap; align-items: flex-end; }
.control-group { display: flex; flex-direction: column; gap: 8px; }
.slider-row { display: flex; align-items: center; gap: 14px; }

.slider {
  -webkit-appearance: none; appearance: none;
  width: 200px; height: 4px; border-radius: 2px;
  background: var(--bg5); outline: none;
}
.slider::-webkit-slider-thumb {
  -webkit-appearance: none; appearance: none;
  width: 18px; height: 18px; border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--cyan));
  cursor: pointer; border: 2px solid var(--bg);
  box-shadow: 0 0 10px var(--accent-glow);
  transition: transform 0.15s;
}
.slider::-webkit-slider-thumb:hover { transform: scale(1.25); }
.slider::-moz-range-thumb {
  width: 18px; height: 18px; border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--cyan));
  cursor: pointer; border: 2px solid var(--bg);
}
.slider-val { font-family: var(--mono); font-size: 16px; font-weight: 700; color: var(--accent2); min-width: 36px; }

.gen-output {
  background: var(--bg2); border: 1.5px solid var(--border2);
  border-radius: var(--radius-xl); padding: 1.5rem 1.75rem; min-height: 120px;
}
.output-empty { color: var(--text3); font-size: 13px; font-family: var(--mono); font-style: italic; }
.output-header {
  display: flex; justify-content: space-between; align-items: flex-start;
  margin-bottom: 1rem; padding-bottom: 12px; border-bottom: 1px solid var(--border2);
}
.output-title { font-size: 13px; font-weight: 600; color: var(--text2); line-height: 1.5; }
.output-count {
  font-family: var(--mono); font-size: 30px; font-weight: 700; line-height: 1;
  background: linear-gradient(135deg, var(--accent2), var(--cyan));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
  animation: countPop 0.4s cubic-bezier(0.34,1.56,0.64,1);
}
@keyframes countPop {
  from { transform: scale(0.5); opacity: 0; }
  to   { transform: scale(1); opacity: 1; }
}
.strings-grid { display: flex; flex-wrap: wrap; gap: 6px; }
.string-pill {
  font-family: var(--mono); font-size: 13px; padding: 5px 14px; border-radius: 20px;
  background: var(--bg3); border: 1.5px solid var(--border2); color: var(--text);
  animation: pillIn 0.3s cubic-bezier(0.34,1.56,0.64,1) backwards;
  transition: border-color var(--tr), color var(--tr), transform var(--tr);
}
.string-pill:hover { border-color: var(--accent); color: var(--accent2); transform: translateY(-2px); }
.string-pill.empty-str { color: var(--amber); border-color: rgba(255,194,58,0.35); background: var(--amber-bg); font-style: italic; }
@keyframes pillIn {
  from { opacity: 0; transform: scale(0.7); }
  to   { opacity: 1; transform: scale(1); }
}

/* ── Buttons ── */
.primary-btn {
  padding: 12px 28px;
  background: linear-gradient(135deg, var(--accent) 0%, #5b48f8 50%, var(--cyan) 100%);
  background-size: 200% 100%; background-position: 0% 0%;
  color: #fff; border: none; border-radius: var(--radius-lg);
  font-family: var(--sans); font-size: 13px; font-weight: 700;
  cursor: pointer; letter-spacing: 0.04em;
  transition: background-position 0.4s, transform var(--tr), box-shadow var(--tr);
  margin-top: 1.25rem; box-shadow: 0 4px 20px var(--accent-glow);
}
.primary-btn:hover {
  background-position: 100% 0%; transform: translateY(-2px);
  box-shadow: 0 8px 32px var(--accent-glow);
}
.primary-btn:active { transform: scale(0.97) translateY(0); }
.primary-btn.compact { margin-top: 0; padding: 12px 22px; white-space: nowrap; }
.primary-btn.large { padding: 15px 48px; font-size: 14px; }

/* ── Tester ── */
.tester-layout { display: grid; grid-template-columns: 1fr 1fr; gap: 2rem; align-items: start; }
#single-result { margin-top: 10px; }
.test-result-badge {
  display: inline-flex; align-items: center; gap: 10px;
  padding: 12px 20px; border-radius: var(--radius-lg);
  font-size: 14px; font-family: var(--mono); font-weight: 500;
  animation: badgeIn 0.4s cubic-bezier(0.34,1.56,0.64,1);
}
@keyframes badgeIn {
  from { transform: scale(0.75); opacity: 0; }
  to   { transform: scale(1); opacity: 1; }
}
.test-result-badge.accepted { background: var(--green-bg); border: 1.5px solid var(--green-bdr); color: var(--green); box-shadow: 0 0 20px rgba(42,255,200,0.12); }
.test-result-badge.rejected { background: var(--red-bg); border: 1.5px solid var(--red-bdr); color: var(--red); box-shadow: 0 0 20px rgba(255,90,126,0.12); }

.batch-textarea {
  width: 100%; height: 160px; padding: 14px 16px;
  font-family: var(--mono); font-size: 13px; line-height: 1.9;
  background: var(--bg3); border: 1.5px solid var(--border2);
  border-radius: var(--radius-lg); color: var(--text);
  outline: none; resize: vertical; caret-color: var(--accent2);
  transition: border-color var(--tr), box-shadow var(--tr), background var(--tr);
}
.batch-textarea:focus { border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-dim); }

.batch-output {
  background: var(--bg2); border: 1.5px solid var(--border2);
  border-radius: var(--radius-xl); padding: 1.25rem 1.5rem; min-height: 300px;
}
.batch-row {
  display: flex; align-items: center; justify-content: space-between;
  padding: 9px 14px; border-radius: var(--radius); margin-bottom: 4px;
  font-family: var(--mono); font-size: 13px;
  animation: rowIn 0.25s ease backwards;
  border: 1.5px solid transparent;
  transition: filter var(--tr);
}
.batch-row:hover { filter: brightness(1.1); }
@keyframes rowIn {
  from { opacity: 0; transform: translateX(-10px); }
  to   { opacity: 1; transform: translateX(0); }
}
.batch-row.acc { background: var(--green-bg); border-color: var(--green-bdr); }
.batch-row.rej { background: var(--red-bg); border-color: var(--red-bdr); }
.batch-str { color: var(--text); letter-spacing: 0.04em; }
.batch-verdict.acc { color: var(--green); font-weight: 600; }
.batch-verdict.rej { color: var(--red); font-weight: 600; }
.batch-summary { font-size: 12px; color: var(--text3); margin-bottom: 12px; font-weight: 500; }

/* ── Equivalence ── */
.equiv-layout { display: flex; flex-direction: column; gap: 1.5rem; }
.equiv-inputs { display: flex; align-items: flex-start; gap: 1.5rem; }
.equiv-re-block { flex: 1; }
.equiv-presets { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 10px; }
.equiv-vs { font-family: var(--mono); font-size: 26px; font-weight: 700; color: var(--text3); padding-top: 36px; user-select: none; }
.equiv-actions { margin-top: 0.25rem; }

.equiv-result-box {
  padding: 1.5rem 2rem; border-radius: var(--radius-xl);
  border: 1.5px solid var(--border2);
  animation: resultReveal 0.45s cubic-bezier(0.22,1,0.36,1);
  overflow: hidden; position: relative;
}
.equiv-result-box::after {
  content: ''; position: absolute; left: 0; top: 0; bottom: 0; width: 4px;
}
@keyframes resultReveal {
  from { opacity: 0; transform: translateY(10px); }
  to   { opacity: 1; transform: translateY(0); }
}
.equiv-result-box.pending { background: var(--bg2); }
.equiv-result-box.pending::after { background: var(--border3); }
.equiv-result-box.equivalent { background: var(--green-bg); border-color: var(--green-bdr); }
.equiv-result-box.equivalent::after { background: var(--green); box-shadow: 0 0 12px rgba(42,255,200,0.4); }
.equiv-result-box.not-equivalent { background: var(--red-bg); border-color: var(--red-bdr); }
.equiv-result-box.not-equivalent::after { background: var(--red); box-shadow: 0 0 12px rgba(255,90,126,0.4); }

.equiv-placeholder { color: var(--text3); font-size: 13px; font-style: italic; }
.equiv-verdict { font-family: var(--sans); font-size: 22px; font-weight: 800; margin-bottom: 8px; letter-spacing: -0.02em; }
.equiv-result-box.equivalent .equiv-verdict { color: var(--green); }
.equiv-result-box.not-equivalent .equiv-verdict { color: var(--red); }
.equiv-sub { font-size: 13px; color: var(--text2); line-height: 1.65; }

#equiv-detail { display: flex; flex-direction: column; gap: 6px; }
.equiv-check-row {
  display: flex; align-items: center; gap: 12px;
  font-size: 13px; font-family: var(--sans);
  padding: 10px 14px; border-radius: var(--radius-lg);
  background: var(--bg2); border: 1.5px solid var(--border);
  animation: rowIn 0.25s ease backwards;
}
.check-icon { font-size: 14px; }
.check-icon.pass { color: var(--green); }
.check-icon.fail { color: var(--red); }
.check-text { color: var(--text2); }
.check-code { font-family: var(--mono); font-size: 12px; color: var(--accent2); padding: 2px 8px; background: var(--bg3); border-radius: var(--radius); border: 1px solid var(--border2); }

/* ── Reference ── */
.ref-layout { display: grid; grid-template-columns: 1fr 1fr; gap: 3rem; }
.ref-heading {
  font-size: 11px; font-weight: 700; text-transform: uppercase;
  letter-spacing: 0.12em; color: var(--accent); margin-bottom: 1rem;
  display: flex; align-items: center; gap: 10px;
}
.ref-heading::after { content: ''; flex: 1; height: 1.5px; background: var(--border2); }
.ref-col { display: flex; flex-direction: column; }

.ref-table { width: 100%; border-collapse: collapse; font-size: 13px; }
.ref-table th { text-align: left; padding: 9px 14px; border-bottom: 1.5px solid var(--border2); color: var(--text3); font-size: 10px; text-transform: uppercase; letter-spacing: 0.1em; font-weight: 700; }
.ref-table td { padding: 9px 14px; border-bottom: 1px solid var(--border); color: var(--text2); font-size: 13px; transition: background var(--tr); }
.ref-table tr:hover td { background: var(--bg2); }
.ref-table tr:last-child td { border-bottom: none; }
.ref-table td code, .ref-table th code { font-family: var(--mono); font-size: 12px; color: var(--accent2); }

.pipeline { display: flex; flex-direction: column; gap: 0; }
.pipe-step {
  display: flex; gap: 18px; align-items: flex-start;
  padding: 18px 22px; background: var(--bg2);
  border: 1.5px solid var(--border2); border-radius: var(--radius-xl);
  transition: border-color var(--tr), transform var(--tr), box-shadow var(--tr);
}
.pipe-step:hover { border-color: var(--accent); transform: translateX(6px); box-shadow: 0 8px 32px var(--shadow2); }
.pipe-arrow { text-align: center; color: var(--text3); font-size: 16px; padding: 5px 0 5px 28px; }
.pipe-num {
  width: 32px; height: 32px; border-radius: var(--radius);
  background: var(--accent-dim); color: var(--accent2);
  font-family: var(--mono); font-size: 12px; font-weight: 700;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0; margin-top: 2px; border: 1.5px solid rgba(124,109,255,0.3);
}
.pipe-title { font-size: 14px; font-weight: 700; color: var(--text); margin-bottom: 5px; }
.pipe-desc { font-size: 12px; color: var(--text2); line-height: 1.7; }

/* ── Footer ── */
.site-footer {
  position: relative; z-index: 1; border-top: 1px solid var(--border2);
  padding: 1.5rem 2rem; text-align: center; font-size: 12px; color: var(--text3);
  background: var(--bg2);
  transition: background var(--tr), border-color var(--tr);
}
.footer-sep { margin: 0 12px; color: var(--border3); }

/* ── Error state ── */
.parse-error {
  padding: 10px 16px; background: var(--red-bg); border: 1.5px solid var(--red-bdr);
  border-radius: var(--radius-lg); color: var(--red); font-size: 13px;
  font-family: var(--mono); margin-top: 8px; animation: errorShake 0.35s ease;
}
@keyframes errorShake {
  0%,100% { transform: translateX(0); }
  20%     { transform: translateX(-5px); }
  60%     { transform: translateX(5px); }
  80%     { transform: translateX(-3px); }
}

/* ── Code ── */
code { font-family: var(--mono); font-size: 0.9em; color: var(--accent2); }

/* ── Example Loader ── */
.example-loader { position: relative; }
.example-trigger {
  display: flex; align-items: center; gap: 8px;
  padding: 8px 16px; border: 1.5px solid var(--border2);
  border-radius: var(--radius-lg); background: var(--bg3);
  color: var(--text2); font-family: var(--sans); font-size: 13px;
  font-weight: 600; cursor: pointer; transition: all var(--tr); white-space: nowrap;
}
.example-trigger:hover { border-color: var(--accent); color: var(--accent2); background: var(--accent-dim); box-shadow: 0 4px 16px var(--shadow2); }
.example-trigger-icon { font-size: 12px; }
.example-caret { font-size: 10px; color: var(--text3); transition: transform 0.2s; }
.example-caret.open { transform: rotate(180deg); }

.example-menu {
  position: absolute; top: calc(100% + 8px); right: 0;
  width: 320px; background: var(--bg2);
  border: 1.5px solid var(--border2); border-radius: var(--radius-xl);
  box-shadow: 0 20px 60px var(--shadow), 0 0 0 1px var(--accent-dim);
  z-index: 200; display: none; overflow: hidden;
  animation: menuIn 0.2s cubic-bezier(0.22,1,0.36,1);
}
.example-menu.open { display: block; }
@keyframes menuIn {
  from { opacity: 0; transform: translateY(-10px) scale(0.95); }
  to   { opacity: 1; transform: translateY(0) scale(1); }
}
.example-menu-header {
  padding: 10px 16px; font-size: 10px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.12em;
  color: var(--accent2); border-bottom: 1px solid var(--border2); background: var(--bg3);
}
.example-list { padding: 6px; display: flex; flex-direction: column; gap: 2px; }
.example-item {
  display: flex; flex-direction: column; gap: 3px;
  padding: 10px 14px; border-radius: var(--radius);
  cursor: pointer; border: 1.5px solid transparent;
  background: transparent; text-align: left; width: 100%; transition: all var(--tr);
}
.example-item:hover { background: var(--bg3); border-color: var(--border2); }
.example-item-re { font-family: var(--mono); font-size: 13px; color: var(--accent2); font-weight: 500; letter-spacing: 0.04em; }
.example-item-desc { font-size: 11px; color: var(--text3); }
.example-item-loaded { background: var(--accent-dim) !important; border-color: rgba(124,109,255,0.25) !important; }
.example-item-loaded .example-item-re { color: var(--text); }
.example-item-loaded .example-item-desc::before { content: '✓ loaded — '; color: var(--green); }

/* ── Scrollbar ── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--border3); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--accent); }

/* ── Focus ring ── */
*:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ── Responsive ── */
@media (max-width: 900px) {
  .builder-layout { grid-template-columns: 1fr; }
  .builder-sidebar { display: none; }
  .tester-layout { grid-template-columns: 1fr; }
  .ref-layout { grid-template-columns: 1fr; }
  .equiv-inputs { flex-direction: column; }
  .equiv-vs { padding-top: 0; align-self: center; }
  .section-hero { flex-direction: column; gap: 0.5rem; }
  .section-hero-num { font-size: 40px; }
}
@media (max-width: 640px) {
  .header-inner { padding: 0 1rem; }
  .main-content { padding: 1.5rem 1rem 3rem; }
  .main-nav { display: none; }
  .section-title { font-size: 24px; }
  .logo-sub { display: none; }
}

/* ── Misc ── */
.re-input:focus::placeholder { opacity: 0.35; }
@keyframes fadeSlideIn {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}
.analysis-grid, .strings-grid { animation: fadeSlideIn 0.3s ease; }