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

:root {
  --ink: #061220;
  --panel: rgba(248, 250, 252, 0.92);
  --panel-border: rgba(0, 18, 40, 0.08);
  --text: #eaf2ff;
  --muted: #c1c9d6;
  --panel-text: #0b1a2c;
  --accent: #0fb07d;
  --accent-2: #2f7bdc;
  --danger: #d14f67;
  --warning: #c47a16;
  --shadow: 0 24px 80px rgba(4, 10, 20, 0.45);
  --radius: 16px;
  --space: 18px;
  font-family: 'Space Grotesk', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  color: var(--text);
  background: #061220;
}

body {
  margin: 0;
  padding: 0;
  min-height: 100vh;
  background: radial-gradient(circle at 18% 18%, rgba(121, 199, 255, 0.2), transparent 32%),
    radial-gradient(circle at 82% 10%, rgba(122, 245, 208, 0.18), transparent 30%),
    radial-gradient(circle at 50% 80%, rgba(98, 130, 255, 0.12), transparent 28%),
    linear-gradient(135deg, #04122a 0%, #061220 50%, #0b1f38 100%);
  color: var(--text);
}

.backdrop {
  position: fixed;
  inset: 0;
  z-index: -1;
  overflow: hidden;
}

.glow {
  position: absolute;
  width: 420px;
  height: 420px;
  filter: blur(90px);
  opacity: 0.55;
  transform: translate(-50%, -50%);
}

.glow-1 {
  top: 30%;
  left: 18%;
  background: #76c0ff;
}

.glow-2 {
  top: 12%;
  left: 70%;
  background: #7af5d0;
}

.glow-3 {
  top: 68%;
  left: 40%;
  background: #0f2340;
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 40px;
  position: sticky;
  top: 0;
  background: linear-gradient(180deg, rgba(5, 9, 20, 0.92), rgba(5, 9, 20, 0.7) 70%, transparent);
  backdrop-filter: blur(8px);
  z-index: 10;
}

.brand {
  display: flex;
  gap: 12px;
  align-items: center;
  text-decoration: none;
  color: inherit;
}

.mark {
  width: 46px;
  height: 46px;
  border-radius: 14px;
  background: conic-gradient(from 120deg, #0fb07d, #2f7bdc, #0fb07d);
  color: #04122a;
  display: grid;
  place-items: center;
  box-shadow: 0 10px 24px rgba(4, 18, 42, 0.35);
}

.mark-glyph {
  font-weight: 800;
  font-size: 30px;
}

.brand-name {
  font-weight: 700;
  letter-spacing: 0.4px;
}

.brand-tagline {
  color: var(--muted);
  font-size: 12px;
}

.top-actions {
  display: flex;
  gap: 10px;
}

.shell {
  max-width: 1360px;
  margin: 0 auto;
  padding: 24px 32px 90px;
}

.hero {
  display: grid;
  grid-template-columns: 1.3fr 0.7fr;
  gap: 26px;
  align-items: center;
  margin: 6px 0 16px;
}

.mode-switch {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  margin: 8px 0 4px;
}

.mode-btn {
  border: 1px solid var(--panel-border);
  background: rgba(255, 255, 255, 0.03);
  color: var(--text);
  padding: 9px 12px;
  border-radius: 12px;
  cursor: pointer;
  font-weight: 700;
  font-size: 13px;
}

.mode-btn.active {
  background: linear-gradient(135deg, #7cb7ff, #6ce3b4);
  color: #041020;
  border: none;
}

.mode-btn.secondary {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--panel-border);
  color: var(--text);
}

.mode-btn.secondary.active {
  background: linear-gradient(135deg, #63e2b5, #7cb7ff);
  color: #041020;
  border: none;
}

.mode-hint {
  margin: 0;
}

.sheet-view {
  display: none;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.sheet-view.visible {
  display: flex;
}

.eyebrow {
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 1.6px;
  font-size: 11px;
  margin: 0 0 6px;
}

h1 {
  margin: 0 0 12px;
  font-size: 24px;
  line-height: 1.16;
  font-weight: 700;
}

.lede {
  color: var(--muted);
  margin: 0 0 16px;
  max-width: 640px;
  font-size: 13px;
  font-weight: 600;
}

.toggles {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.toggle {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 12px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--panel-border);
  border-radius: 14px;
  color: var(--text);
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  white-space: nowrap;
}

.toggle input {
  accent-color: var(--accent);
  cursor: pointer;
}

.stats-card {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
  padding: 12px;
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  color: var(--panel-text);
}

.stat {
  padding: 10px;
  background: rgba(12, 23, 42, 0.04);
  border-radius: 12px;
  border: 1px solid var(--panel-border);
}

.stat-label {
  color: #4a5a6f;
  font-size: 11px;
}

.stat-value {
  font-size: 18px;
  font-weight: 700;
  margin-top: 4px;
  color: var(--panel-text);
}

.stat-value.accent {
  color: var(--accent);
}

.workspace {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 18px;
  margin-bottom: 8px;
}

.editor {
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  color: var(--panel-text);
}

.swap-middle {
  display: grid;
  align-items: center;
  justify-items: center;
}

.swap-circle {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: 1px solid var(--panel-border);
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  font-size: 22px;
  cursor: pointer;
  box-shadow: var(--shadow);
}

.swap-circle:hover {
  transform: translateY(-1px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.25);
}

.upload-row {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 16px 0;
  flex-wrap: wrap;
}

.upload-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 12px;
  border-radius: 12px;
  background: rgba(12, 23, 42, 0.08);
  border: 1px dashed var(--panel-border);
  color: var(--panel-text);
  cursor: pointer;
  font-weight: 600;
}

.file-input {
  display: none;
}

.file-name {
  color: var(--muted);
  font-size: 12px;
}

.editor-head {
  padding: 16px;
  border-bottom: 1px solid var(--panel-border);
  display: flex;
  align-items: center;
  gap: 10px;
}

.label {
  font-size: 13px;
  letter-spacing: 0.6px;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 700;
  margin: 0;
}

.hint {
  color: #4a5a6f;
  font-size: 12px;
  margin: 2px 0 0;
}

textarea {
  width: 100%;
  min-height: 360px;
  border: none;
  padding: 16px;
  resize: vertical;
  background: rgba(255, 255, 255, 0.85);
  color: var(--panel-text);
  font-family: 'Space Grotesk', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, 'Liberation Mono', 'Courier New', monospace;
  font-size: 15px;
  line-height: 1.5;
  border-left: 1px solid var(--panel-border);
}

textarea:focus {
  outline: 2px solid rgba(124, 183, 255, 0.45);
  outline-offset: -4px;
}

textarea.readonly {
  opacity: 0.8;
}

.sheet-only {
  display: none;
  padding: 16px;
  color: var(--muted);
  font-size: 14px;
}

.doc-only {
  display: none;
  padding: 16px;
  color: var(--muted);
  font-size: 14px;
}

.hidden {
  display: none !important;
}

.editor-body {
  display: grid;
  grid-template-columns: auto 1fr;
  align-items: stretch;
}

.line-numbers {
  width: 54px;
  padding: 16px 10px;
  border-right: 1px solid var(--panel-border);
  color: #70819a;
  font-family: 'Space Grotesk', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, 'Liberation Mono', 'Courier New', monospace;
  font-size: 13px;
  line-height: 1.5;
  background: rgba(255, 255, 255, 0.02);
  white-space: pre;
  overflow: hidden;
}

.controls {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  grid-template-areas: "left center right";
  align-items: center;
  gap: 12px;
  margin: 6px 0 12px;
}

.control-left {
  display: flex;
  gap: 10px;
  flex-wrap: nowrap;
  align-items: center;
  justify-content: flex-start;
  grid-area: left;
  overflow-x: auto;
  scrollbar-width: thin;
}

.control-center {
  display: flex;
  justify-content: center;
  grid-area: center;
}

.control-right {
  display: flex;
  gap: 10px;
  justify-content: flex-end;
  grid-area: right;
}

.slider-toggle {
  gap: 10px;
}

.slider-toggle input[type='range'] {
  accent-color: var(--accent-2);
  cursor: pointer;
}

.slider-value {
  color: var(--muted);
  font-size: 12px;
}

.ghost-btn,
.primary-btn {
  border-radius: 12px;
  padding: 12px 16px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  border: 1px solid var(--panel-border);
  background: rgba(255, 255, 255, 0.03);
  color: var(--text);
  transition: transform 160ms ease, box-shadow 160ms ease, background 160ms ease;
}

.ghost-btn:hover,
.primary-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.25);
}

.primary-btn {
  background: linear-gradient(135deg, #7cb7ff, #6ce3b4);
  color: #041020;
  border: none;
}

.results {
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  color: var(--panel-text);
}

.results-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px;
  border-bottom: 1px solid var(--panel-border);
}

.results-actions {
  display: flex;
  gap: 8px;
  align-items: center;
}

.minimap {
  height: 14px;
  border-bottom: 1px solid var(--panel-border);
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(2px, 1fr);
  overflow: hidden;
}

.mini-bar {
  height: 100%;
  opacity: 0.8;
}

.mini-bar.add {
  background: linear-gradient(90deg, rgba(108, 227, 180, 0.9), rgba(108, 227, 180, 0.6));
}

.mini-bar.remove {
  background: linear-gradient(90deg, rgba(255, 123, 138, 0.9), rgba(255, 123, 138, 0.6));
}

.mini-bar.same {
  background: linear-gradient(90deg, rgba(124, 183, 255, 0.9), rgba(124, 183, 255, 0.6));
}

.mini-bar.change {
  background: linear-gradient(90deg, rgba(255, 193, 107, 0.9), rgba(255, 193, 107, 0.6));
}

.diff-results {
  display: grid;
  min-height: 180px;
}

.diff-results.split {
  grid-template-columns: repeat(2, 1fr);
}

.diff-results.inline {
  grid-template-columns: 1fr;
}

.diff-column {
  border-right: 1px solid rgba(0, 0, 0, 0.22);
}

.diff-column:last-child {
  border-right: none;
}

.line {
  display: grid;
  grid-template-columns: 60px 1fr;
  gap: 12px;
  padding: 10px 14px;
  align-items: start;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
}

.line:last-child {
  border-bottom: none;
}

.line-number {
  color: #3d5066;
  font-size: 12px;
}

.line-content {
  white-space: pre-wrap;
  word-break: break-word;
}

.line.add {
  background: linear-gradient(90deg, rgba(108, 227, 180, 0.08), transparent);
}

.line.remove {
  background: linear-gradient(90deg, rgba(255, 123, 138, 0.1), transparent);
}

.line.change {
  background: linear-gradient(90deg, rgba(124, 183, 255, 0.08), transparent);
}

.line.same {
  background: transparent;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: 10px;
  font-size: 12px;
  border: 1px solid var(--panel-border);
  color: var(--muted);
}

.pill.add {
  color: #0d3324;
  background: rgba(15, 176, 125, 0.16);
  border: 1px solid rgba(15, 176, 125, 0.4);
  font-weight: 800;
  letter-spacing: 0.6px;
}

.pill.remove {
  color: #2a0d14;
  background: rgba(255, 123, 138, 0.9);
  border: none;
}

.pill.same {
  color: #0c1020;
  background: rgba(124, 183, 255, 0.85);
  border: none;
}

.char-add {
  background: rgba(108, 227, 180, 0.3);
}

.char-remove {
  background: rgba(255, 123, 138, 0.3);
}

.empty-state {
  padding: 40px;
  color: var(--muted);
}

.sheet-table {
  width: 100%;
  border-collapse: collapse;
}

.sheet-table th,
.sheet-table td {
  padding: 10px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  text-align: left;
}

.sheet-table thead {
  background: rgba(255, 255, 255, 0.04);
}

.sheet-table tr.add {
  background: linear-gradient(90deg, rgba(108, 227, 180, 0.08), transparent);
}

.sheet-table tr.remove {
  background: linear-gradient(90deg, rgba(255, 123, 138, 0.1), transparent);
}

.sheet-table tr.change {
  background: linear-gradient(90deg, rgba(255, 193, 107, 0.12), transparent);
}

.sheet-table tr.same {
  background: transparent;
}

.sheet-table td.add {
  background: linear-gradient(90deg, rgba(108, 227, 180, 0.08), transparent);
}

.sheet-table td.remove {
  background: linear-gradient(90deg, rgba(255, 123, 138, 0.1), transparent);
}

.sheet-table td.change {
  background: linear-gradient(90deg, rgba(255, 193, 107, 0.12), transparent);
}

.sheet-table td.same {
  background: transparent;
}

.site-footer {
  margin-top: 40px;
  background: linear-gradient(180deg, rgba(4, 12, 26, 0.94), rgba(4, 12, 26, 0.88));
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  backdrop-filter: blur(8px);
}

.footer-inner {
  max-width: 1360px;
  margin: 0 auto;
  padding: 26px 32px 34px;
  text-align: center;
  color: var(--text);
}

.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 10px;
}

.mark-compact {
  width: 40px;
  height: 40px;
  border-radius: 12px;
}

.footer-title {
  font-weight: 800;
  letter-spacing: 0.8px;
  font-size: 16px;
}

.footer-text,
.footer-meta {
  margin: 6px 0;
  color: var(--muted);
  font-size: 13px;
}

.footer-meta {
  color: #9ab2d0;
  font-weight: 600;
}

@media (max-width: 960px) {
  .hero {
    grid-template-columns: 1fr;
  }
  .workspace {
    grid-template-columns: 1fr;
  }
  .diff-results.split {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .topbar {
    padding: 14px 16px;
    flex-direction: column;
    gap: 10px;
    align-items: flex-start;
  }
  .controls {
    flex-direction: column;
    align-items: flex-start;
  }
  textarea {
    min-height: 220px;
  }
}