:root{
  /* Theme colors - set to undefined to force external override, or keep defaults */
  --color-primary: #0ea5e9;   /* sky-500 */
  --color-primary-600: #0284c7;
  --color-secondary: #64748b; /* slate-500 */
  --color-bg: #ffffff;
  --color-bg-soft: #f8fafc;   /* slate-50 */
  --color-text: #0f172a;      /* slate-900 */
  --color-muted: #475569;     /* slate-600 */
  --color-border: #e2e8f0;    /* slate-200 */
  --color-added-bg: #ecfdf5;  /* emerald-50 */
  --color-del-bg: #fef2f2;    /* rose-50 */
  --color-mod-bg: #fff7ed;    /* orange-50 */
  --color-move-bg: #eff6ff;   /* blue-50 */
  --color-added-border: #10b981;
  --color-del-border: #ef4444;
  --color-mod-border: #f59e0b;
  --color-move-border: #3b82f6;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 8px rgba(0,0,0,0.08);
  --radius: 10px;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body{
  margin:0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Apple Color Emoji", "Segoe UI Emoji";
  color: var(--color-text);
  background: var(--color-bg);
}

.app-header{
  position: sticky; top: 0; z-index: 10;
  display: flex; align-items: center; justify-content: space-between;
  padding: 12px 16px;
  border-bottom: 1px solid var(--color-border);
  background: linear-gradient(180deg, var(--color-bg) 0%, var(--color-bg-soft) 100%);
  backdrop-filter: blur(4px);
}

.brand{ display: flex; align-items: center; gap: 10px; }
.brand .logo{
  width: 32px; height: 32px; display: grid; place-items:center;
  border-radius: 8px; background: var(--color-primary);
  color: white; font-weight: 700;
  box-shadow: var(--shadow-sm);
}
h1{ font-size: 18px; margin: 0; }
.header-actions{ display: flex; align-items: center; gap: 16px; }

.btn-info{
  width: 32px; height: 32px; border-radius: 8px; border: 1px solid var(--color-border);
  background: var(--color-bg); color: var(--color-muted); cursor: pointer; display: grid; place-items: center;
  transition: background .2s ease, color .2s ease;
}
.btn-info:hover{ background: var(--color-primary); color: white; }
.switch{ display: inline-flex; align-items: center; gap: 8px; cursor: pointer; user-select: none; }
.switch input{ display: none; }
.switch .slider{
  width: 40px; height: 22px; border-radius: 999px; background: var(--color-border);
  position: relative; transition: background .2s ease;
}
.switch .slider::after{
  content:""; position: absolute; top: 3px; left: 3px;
  width: 16px; height: 16px; border-radius: 50%; background: white; box-shadow: var(--shadow-sm);
  transition: transform .2s ease;
}
.switch input:checked + .slider{ background: var(--color-primary); }
.switch input:checked + .slider::after{ transform: translateX(18px); }
.switch .switch-label{ color: var(--color-muted); font-size: 14px; }
.search-container{
  position: relative; display: flex; align-items: center;
  border: 1px solid var(--color-border); border-radius: 8px; background: var(--color-bg);
  overflow: hidden;
}
.search-input{
  border: none; padding: 6px 10px; background: transparent; color: var(--color-text);
  width: 200px; font-size: 14px;
}
.search-input:focus{ outline: none; }
.search-btn{
  border: none; background: transparent; color: var(--color-muted); cursor: pointer;
  padding: 6px 10px; display: flex; align-items: center; justify-content: center;
  transition: background .2s ease;
}
.search-btn:hover{ background: var(--color-bg-soft); color: var(--color-primary); }

.controls{
  display: grid; grid-template-columns: 1fr 1fr; gap: 12px;
  padding: 12px 16px;
}
.file-block{
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-bg);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}
.block-header{
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 10px 12px;
  border-bottom: 1px solid var(--color-border);
  background: var(--color-bg-soft);
}
.file-actions{ display: flex; align-items: center; gap: 8px; }
.btn{
  background: var(--color-primary); color: white; border: none; border-radius: 8px;
  padding: 8px 12px; cursor: pointer; box-shadow: var(--shadow-sm);
  transition: transform .05s ease, background .2s ease;
}
.btn:hover{ background: var(--color-primary-600); }
.btn:active{ transform: translateY(1px); }
.btn.secondary{
  background: var(--color-secondary);
}
.btn.ghost{
  background: transparent; color: var(--color-text); border: 1px solid var(--color-border);
}
.btn.small{
  padding: 4px 8px; font-size: 12px; border-radius: 6px;
}
.file-summary{ padding: 8px 12px; color: var(--color-muted); font-size: 14px; }
.textarea-wrap{ padding: 10px; border-top: 1px dashed var(--color-border); background: var(--color-bg-soft); }
.textarea-wrap textarea{
  width: 100%; min-height: 160px; resize: vertical; padding: 10px; border-radius: 8px;
  border: 1px solid var(--color-border); background: white; color: var(--color-text);
}
.paste-actions{ display:flex; gap: 8px; margin-top: 8px; }
.stats{
  display: flex; gap: 16px; align-items: center;
  padding: 8px 16px; color: var(--color-muted);
}
.stat{ display: inline-flex; gap: 6px; align-items: center; background: var(--color-bg-soft); border: 1px solid var(--color-border); padding: 6px 10px; border-radius: 999px; }
.stat .label{ font-size: 12px; }
.stat .value{ font-weight: 700; color: var(--color-text); }

.analytics{
  margin: 0 16px; border: 1px solid var(--color-border); border-radius: var(--radius);
  background: var(--color-bg); box-shadow: var(--shadow-sm); overflow: hidden;
}
.analytics-header{
  display: flex; align-items: center; justify-content: space-between; padding: 12px 16px;
  border-bottom: 1px solid var(--color-border); background: var(--color-bg-soft);
}
.analytics-header h3{ margin: 0; font-size: 16px; }
.analytics-controls{ display: flex; gap: 8px; }
.analytics-content{
  display: grid; grid-template-columns: 1fr 1fr; gap: 20px; padding: 16px;
}
.chart-container h4{
  margin: 0 0 12px 0; font-size: 14px; color: var(--color-muted);
}
.bar-chart{
  display: flex; flex-direction: column; gap: 8px; min-height: 120px;
}
.bar-item{
  display: flex; align-items: center; gap: 10px;
}
.bar-label{
  min-width: 60px; font-size: 12px; color: var(--color-muted);
}
.bar-track{
  flex: 1; height: 20px; background: var(--color-bg-soft); border-radius: 10px; position: relative; overflow: hidden;
}
.bar-fill{
  height: 100%; border-radius: 10px; transition: width .3s ease; position: relative;
}
.bar-value{
  min-width: 30px; text-align: right; font-size: 12px; font-weight: 600;
}
.bar-fill.added{ background: linear-gradient(90deg, var(--color-added-border), #34d399); }
.bar-fill.deleted{ background: linear-gradient(90deg, var(--color-del-border), #f87171); }
.bar-fill.modified{ background: linear-gradient(90deg, var(--color-mod-border), #fbbf24); }
.bar-fill.moved{ background: linear-gradient(90deg, var(--color-move-border), #60a5fa); }

.change-heatmap{
  display: grid; grid-template-rows: auto 1fr; gap: 12px;
}
.heatmap-header{
  display: flex; align-items: center; justify-content: space-between;
}
.heatmap-grid{
  display: flex; flex-direction: column; gap: 2px; max-height: 200px; overflow-y: auto;
  border: 1px solid var(--color-border); border-radius: 8px; padding: 8px;
  background: var(--color-bg-soft);
}
.heatmap-row{
  display: grid; grid-template-columns: 1fr auto; gap: 8px; align-items: center;
  padding: 2px 0; border-radius: 4px; transition: background .2s ease;
}
.heatmap-row:hover{ background: var(--color-border); }
.heatmap-line{
  height: 4px; border-radius: 2px; transition: all .2s ease;
}
.heatmap-label{
  font-size: 10px; color: var(--color-muted);
}

.diff-container{
  position: relative;
  display: grid; grid-template-columns: 1fr 1fr; gap: 12px;
  padding: 12px 16px 24px;
}
.pane-wrapper{
  position: relative; display: contents;
}
.pane{
  display:flex; flex-direction: column; min-height: 60vh; border: 1px solid var(--color-border);
  border-radius: var(--radius); overflow: hidden; background: var(--color-bg);
  box-shadow: var(--shadow-sm);
}
.pane-header{
  display:flex; align-items: baseline; justify-content: space-between; gap: 10px;
  padding: 10px 12px; border-bottom: 1px solid var(--color-border); background: var(--color-bg-soft);
}
.pane-header h2{ margin: 0; font-size: 16px; }
.file-meta{ color: var(--color-muted); font-size: 12px; }

.code-wrap{ overflow: auto; height: 100%; }
table.code{ width: 100%; border-collapse: separate; border-spacing: 0; table-layout: fixed; }
tbody tr{ border-bottom: 1px solid var(--color-border); }
tbody tr:last-child{ border-bottom: none; }
td{
  padding: 6px 10px; vertical-align: top; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  font-size: 13px; line-height: 1.45;
}
.gutter{ width: 64px; color: var(--color-muted); background: var(--color-bg); border-right: 1px solid var(--color-border); text-align: right; user-select: none; }
.content{ white-space: pre-wrap; word-break: break-word; }

.line.added{ background: var(--color-added-bg); }
.line.added .content{ border-left: 3px solid var(--color-added-border); padding-left: 7px; }
.line.deleted{ background: var(--color-del-bg); }
.line.deleted .content{ border-left: 3px solid var(--color-del-border); padding-left: 7px; }
.line.modified{ background: var(--color-mod-bg); }
.line.modified .content{ border-left: 3px solid var(--color-mod-border); padding-left: 7px; }
.line.moved{ background: var(--color-move-bg); }
.line.moved .content{ border-left: 3px solid var(--color-move-border); padding-left: 7px; }
.line.equal .content{ color: var(--color-text); }

.line .actions{
  display: inline-flex; gap: 6px; margin-left: 8px; opacity: 0; transition: opacity .15s ease;
}
tr:hover .line .actions{ opacity: 1; }

.btn-jump{
  border: none; background: transparent; color: var(--color-muted); cursor: pointer; padding: 2px 4px;
  border-radius: 6px;
}
.btn-jump:hover{ color: var(--color-primary); background: rgba(14,165,233,0.08); }
.jump-indicator{ color: var(--color-primary); font-weight: 700; }

.line-connectors{
  position: absolute; top: 0; left: 0; right: 0; bottom: 0; pointer-events: none; z-index: 5;
  overflow: visible;
}
.connector-line{
  stroke: var(--color-primary); stroke-width: 1; fill: none; opacity: 0.4;
  stroke-dasharray: 3,3; animation: dash 2s linear infinite;
}
@keyframes dash{
  to{ stroke-dashoffset: -6; }
}
.connector-line.moved{ stroke: var(--color-move-border); }
.connector-line.modified{ stroke: var(--color-mod-border); }

.word-diff{
  display: inline; position: relative;
}
.word-diff.added{
  background: rgba(16, 185, 129, 0.3); color: var(--color-text);
  border-radius: 2px; padding: 1px 2px;
}
.word-diff.deleted{
  background: rgba(239, 68, 68, 0.3); color: var(--color-text);
  border-radius: 2px; padding: 1px 2px; text-decoration: line-through;
}

.hover-preview{
  position: absolute; background: var(--color-bg); border: 1px solid var(--color-border);
  border-radius: 6px; padding: 8px; box-shadow: var(--shadow-md); z-index: 20;
  font-size: 12px; max-width: 200px; white-space: pre-wrap;
  opacity: 0; transform: translateY(-10px); transition: all .2s ease;
  pointer-events: none;
}
.hover-preview.show{
  opacity: 1; transform: translateY(0);
}

.minimap{
  position: fixed; right: 20px; top: 50%; transform: translateY(-50%);
  width: 120px; background: var(--color-bg); border: 1px solid var(--color-border);
  border-radius: var(--radius); box-shadow: var(--shadow-md); z-index: 15;
  max-height: 60vh; overflow: hidden;
}
.minimap-header{
  padding: 8px 12px; border-bottom: 1px solid var(--color-border); background: var(--color-bg-soft);
}
.minimap-header h4{
  margin: 0; font-size: 12px; color: var(--color-muted);
}
.minimap-content{
  padding: 8px; height: 200px; overflow-y: auto;
}
.minimap-block{
  height: 3px; margin: 1px 0; border-radius: 2px; cursor: pointer;
  transition: all .2s ease;
}
.minimap-block:hover{
  transform: scaleY(2);
}
.minimap-block.added{ background: var(--color-added-border); }
.minimap-block.deleted{ background: var(--color-del-border); }
.minimap-block.modified{ background: var(--color-mod-border); }
.minimap-block.moved{ background: var(--color-move-border); }
.minimap-block.equal{ background: var(--color-border); opacity: 0.3; }

.search-highlight{
  background: rgba(14, 165, 233, 0.3) !important;
  animation: highlight-pulse 1s ease-in-out;
}
@keyframes highlight-pulse{
  0%{ background: rgba(14, 165, 233, 0.5); }
  50%{ background: rgba(14, 165, 233, 0.2); }
  100%{ background: rgba(14, 165, 233, 0.3); }
}

.change-severity{
  position: absolute; right: 4px; top: 2px; width: 3px; height: calc(100% - 4px);
  border-radius: 2px;
}
.change-severity.low{ background: rgba(34, 197, 94, 0.3); }
.change-severity.medium{ background: rgba(251, 191, 36, 0.5); }
.change-severity.high{ background: rgba(239, 68, 68, 0.7); }

.app-footer{
  padding: 12px 16px; border-top: 1px solid var(--color-border); color: var(--color-muted);
  background: var(--color-bg-soft);
}
.hidden{ display: none !important; }
/* Modal styles */
.modal-overlay{
  position: fixed; top: 0; left: 0; right: 0; bottom: 0; z-index: 50;
  display: flex; align-items: center; justify-content: center;
  background: rgba(0, 0, 0, 0.6); backdrop-filter: blur(2px);
  animation: fadeIn .2s ease;
}

.modal{
  background: var(--color-bg); border-radius: 12px; border: 1px solid var(--color-border);
  width: 90%; max-width: 640px; max-height: 80vh; overflow: hidden; box-shadow: var(--shadow-md);
  animation: slideUp .2s ease;
}

.modal-header{
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 16px 20px; border-bottom: 1px solid var(--color-border); background: var(--color-bg-soft);
}
.modal-header h3{ margin: 0; font-size: 18px; }

.modal-close{
  border: none; background: transparent; cursor: pointer; color: var(--color-muted);
  width: 32px; height: 32px; border-radius: 6px; display: grid; place-items: center;
  transition: background .2s ease, color .2s ease;
}
.modal-close:hover{ background: var(--color-border); color: var(--color-text); }

.modal-content{
  padding: 20px; overflow-y: auto; max-height: calc(80vh - 70px);
}

.modal-section{
  margin-bottom: 24px;
}
.modal-section:last-child{
  margin-bottom: 0;
}
.modal-section h4{
  margin: 0 0 10px 0; font-size: 16px; color: var(--color-text);
}
.modal-section p{
  margin: 0 0 10px 0; line-height: 1.5; color: var(--color-muted);
}
.modal-section ul{
  margin: 0; padding-left: 20px; color: var(--color-muted);
}
.modal-section li{
  margin-bottom: 6px; line-height: 1.4;
}
.modal-section strong{
  color: var(--color-text);
}

@media (max-width: 980px){
  .controls{ grid-template-columns: 1fr; }
  .diff-container{ grid-template-columns: 1fr; }
  .modal{ width: 95%; max-height: 85vh; }
}

@keyframes fadeIn{
  from{ opacity: 0; }
  to{ opacity: 1; }
}

@keyframes slideUp{
  from{ transform: translateY(20px); opacity: 0; }
  to{ transform: translateY(0); opacity: 1; }
}