:root {
  --bg: #0f1115;
  --panel: rgba(10, 13, 18, 0.74);
  --panel-2: rgba(255, 255, 255, 0.06);
  --border: rgba(255, 255, 255, 0.10);
  --border-strong: rgba(255, 255, 255, 0.18);
  --text: rgba(255, 255, 255, 0.96);
  --muted: rgba(255, 255, 255, 0.68);
  --accent: #62c6ff;
  --accent-2: rgba(98, 198, 255, 0.22);
  --shadow: 0 12px 30px rgba(0, 0, 0, 0.28);
}

html, body {
  margin: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: var(--bg);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  color: var(--text);
}

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

#app {
  position: relative;
  width: 100vw;
  height: 100vh;
  overflow: hidden;
  display: flex;
  flex-direction: row;
  background: var(--bg);
}

#viewer {
  position: relative;
  flex: 1;
  min-width: 0;
  height: 100%;
  overflow: hidden;
}

.layer {
  position: absolute;
  inset: 0;
  overflow: hidden;
}

.layer canvas {
  display: block;
  width: 100% !important;
  height: 100% !important;
}

#layer-right {
  z-index: 10;
}

#layer-left {
  z-index: 20;
  clip-path: inset(0 50% 0 0);
  -webkit-clip-path: inset(0 50% 0 0);
}

#interaction-layer {
  position: absolute;
  inset: 0;
  z-index: 30;
  pointer-events: auto;
  background: transparent;
}

#ui {
  position: absolute;
  inset: 0;
  z-index: 50;
  pointer-events: none;
}

.label {
  position: absolute;
  top: 14px;
  padding: 7px 11px;
  background: rgba(0, 0, 0, 0.36);
  color: white;
  border-radius: 10px;
  font-size: 13px;
  pointer-events: none;
  user-select: none;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  z-index: 1;
}

#label-left {
  left: 14px;
}

#label-right {
  right: 14px;
}

#divider {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 50%;
  width: 4px;
  transform: translateX(-2px);
  pointer-events: none;
  border-left: 1px solid rgba(255,255,255,0.30);
  border-right: 1px solid rgba(255,255,255,0.12);
  background: rgba(255,255,255,0.10);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  box-shadow:
    0 0 0 1px rgba(255,255,255,0.06) inset,
    0 0 16px rgba(0,0,0,0.18);
}

#handle {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 50%;
  width: 12px;
  transform: translateX(-6px);
  cursor: ew-resize;
  pointer-events: auto;
  touch-action: none;
  background: transparent;
}

#handle::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 14px;
  height: 60px;
  transform: translate(-50%, -50%);
  border-radius: 999px;
  background: rgba(255,255,255,0.16);
  border: 1px solid rgba(255,255,255,0.40);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  box-shadow:
    0 0 0 1px rgba(255,255,255,0.08) inset,
    0 6px 12px rgba(0,0,0,0.25);
}

#handle::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 6px;
  height: 22px;
  transform: translate(-50%, -50%);
  border-radius: 3px;
  background:
    linear-gradient(
      to right,
      rgba(255,255,255,0.75) 0px,
      rgba(255,255,255,0.75) 1px,
      transparent 1px,
      transparent 2px,
      rgba(255,255,255,0.75) 2px,
      rgba(255,255,255,0.75) 3px,
      transparent 3px,
      transparent 4px,
      rgba(255,255,255,0.75) 4px,
      rgba(255,255,255,0.75) 5px,
      transparent 5px
    );
  opacity: 0.8;
  pointer-events: none;
}

#topbar {
  display: flex;
  flex-direction: column;
  gap: 10px;
  align-items: stretch;
  justify-content: flex-start;
  padding: 0;
  border-radius: 0;
  background: transparent;
  border: 0;
  box-shadow: none;
  pointer-events: auto;
}

#brand {
  min-width: 0;
}

#brand-title {
  font-size: 21px;
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: 0.01em;
}

#brand-subtitle {
  font-size: 12px;
  color: var(--muted);
  margin-top: 4px;
}

#brand-details {
  margin-top: 10px;
  font-size: 11px;
  color: var(--muted);
}

#brand-details-summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 4px;
  color: var(--accent);
  font-weight: 500;
  user-select: none;
}

#brand-details-summary::-webkit-details-marker,
#brand-details-summary::marker {
  display: none;
}

#brand-details-summary::before {
  content: "▶";
  font-size: 8px;
  transition: transform 0.2s ease;
  display: inline-block;
}

#brand-details[open] #brand-details-summary::before {
  transform: rotate(90deg);
}

#brand-authors {
  margin-top: 8px;
  padding-top: 8px;
  border-top: 1px solid var(--border);
}

.brand-co-first {
  display: block;
  font-size: 10px;
  opacity: 0.85;
  margin-bottom: 6px;
}

.brand-author-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 2px 0;
}

.brand-author-list a {
  color: var(--text);
  text-decoration: none;
}

.brand-author-list a:hover {
  color: var(--accent);
  text-decoration: underline;
}

.brand-sep {
  margin: 0 5px;
  opacity: 0.6;
}

.brand-institutes {
  margin-top: 6px;
  font-size: 10px;
  opacity: 0.9;
}

.brand-institutes a {
  color: var(--text);
  text-decoration: none;
}

.brand-institutes a:hover {
  color: var(--accent);
  text-decoration: underline;
}

#brand-badges {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-top: 10px;
  padding-top: 8px;
  border-top: 1px solid var(--border);
}

.brand-badge-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 6px;
  width: 100%;
}

.brand-bibtex-summary {
  cursor: pointer;
  list-style: none;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 11px;
  color: var(--accent);
  font-weight: 500;
  user-select: none;
  margin-top: 8px;
}

.brand-bibtex-summary::-webkit-details-marker,
.brand-bibtex-summary::marker {
  display: none;
}

.brand-bibtex-summary::before {
  content: "▶";
  font-size: 8px;
  transition: transform 0.2s ease;
  display: inline-block;
}

#brand-bibtex[open] .brand-bibtex-summary::before {
  transform: rotate(90deg);
}

.brand-bibtex-code {
  margin: 0;
  margin-top: 6px;
  padding: 6px 0;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 11px;
  overflow-x: auto;
  white-space: pre;
}

/* BibTeX scrollbar – match other subtle scrollbars */
.brand-bibtex-code::-webkit-scrollbar {
  height: 6px;
}

.brand-bibtex-code::-webkit-scrollbar-track {
  background: transparent;
}

.brand-bibtex-code::-webkit-scrollbar-thumb {
  border-radius: 999px;
  background: rgba(255,255,255,0.2);
  box-shadow: 0 0 0 1px rgba(0,0,0,0.35);
}

.brand-bibtex-code::-webkit-scrollbar-thumb:hover {
  background: rgba(255,255,255,0.3);
}

.brand-bibtex-code {
  scrollbar-width: thin;
  scrollbar-color: rgba(255,255,255,0.2) transparent;
}

.brand-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 4px 8px;
  font-size: 11px;
  color: var(--muted);
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 6px;
  text-decoration: none;
  transition: color 0.15s ease, border-color 0.15s ease, background 0.15s ease;
}

.brand-badge:hover {
  color: var(--accent);
  border-color: var(--accent-2);
  background: var(--accent-2);
}

#controls {
  display: flex;
  flex-direction: column;
  flex-wrap: nowrap;
  justify-content: flex-start;
  gap: 10px;
  align-items: stretch;
}

.controls-row {
  display: flex;
  flex-direction: row;
  gap: 10px;
}

.controls-row .file-btn,
.controls-row #btn-simplify {
  flex: 1 1 0;
}

.controls-row-example .control-group-example {
  flex: 1 1 100%;
  min-width: 0;
}

/* Custom example dropdown (trigger + options list matching panel UI) */
.example-dropdown {
  position: relative;
  width: 100%;
  min-width: 0;
}

.example-dropdown-trigger {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  padding: 7px 8px 7px 10px;
  font-size: 14px;
  font-family: inherit;
  color: var(--text);
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid var(--border-strong);
  border-radius: 8px;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease, box-shadow 0.15s ease;
  text-align: left;
}
.example-dropdown-trigger:hover {
  background: rgba(255, 255, 255, 0.14);
}
.example-dropdown-trigger:focus {
  outline: none;
  border-color: rgba(98, 198, 255, 0.85);
  box-shadow: 0 0 0 3px rgba(98, 198, 255, 0.22);
}
.example-dropdown-label {
  flex: 1;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.example-dropdown-chevron {
  flex-shrink: 0;
  width: 12px;
  height: 12px;
  opacity: 0.9;
  background: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12' fill='%2362c6ff'%3E%3Cpath d='M2.5 4.5L6 8l3.5-3.5'/%3E%3C/svg%3E") no-repeat center;
  transition: transform 0.2s ease;
}
.example-dropdown[data-open="true"] .example-dropdown-chevron {
  transform: rotate(180deg);
}

.example-dropdown-list {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  margin-top: 4px;
  padding: 6px 0;
  max-height: 220px;
  overflow-y: auto;
  background: var(--panel);
  border: 1px solid var(--border-strong);
  border-radius: 10px;
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  z-index: 100;
}
.example-dropdown-list[hidden] {
  display: none;
}

/* Example dropdown custom scrollbar – match app style */
.example-dropdown-list::-webkit-scrollbar {
  width: 6px;
}

.example-dropdown-list::-webkit-scrollbar-track {
  background: transparent;
}

.example-dropdown-list::-webkit-scrollbar-thumb {
  border-radius: 999px;
  background: rgba(255,255,255,0.18);
  box-shadow: 0 0 0 1px rgba(0,0,0,0.35);
}

.example-dropdown-list::-webkit-scrollbar-thumb:hover {
  background: rgba(255,255,255,0.28);
}

.example-dropdown-list {
  scrollbar-width: thin;
  scrollbar-color: rgba(255,255,255,0.18) transparent;
}

.example-dropdown-option {
  display: block;
  width: 100%;
  padding: 8px 12px;
  font-size: 14px;
  font-family: inherit;
  color: var(--text);
  background: transparent;
  border: none;
  cursor: pointer;
  text-align: left;
  transition: background 0.12s ease;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.example-dropdown-option:hover {
  background: rgba(255, 255, 255, 0.1);
}
.example-dropdown-option[aria-selected="true"] {
  background: var(--accent-2);
  color: var(--text);
}
.example-dropdown-option[data-value="__custom__"] {
  color: var(--muted);
}

.hyper-params {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 12px;
  padding: 10px;
  border-radius: 14px;
  background: var(--panel-2);
  border: 1px solid var(--border);
}

.hyper-params .control-group {
  padding: 0;
  background: transparent;
  border: 0;
}

.hyper-params .control-group-wide {
  flex: 1 1 100%;
  min-width: 0;
}

.hyper-params .control-group-half {
  flex: 1 1 0;
  min-width: 120px;
}

.file-btn,
#btn-simplify {
  width: 100%;
  justify-content: center;
}

.file-btn {
  text-align: center;
}

.sidepanel-divider {
  height: 1px;
  width: 100%;
  background: rgba(255,255,255,0.10);
  opacity: 0.9;
}

.control-group {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  gap: 6px;
  padding: 8px 10px;
  border-radius: 12px;
  background: var(--panel-2);
  border: 1px solid var(--border);
}

.control-group-wide {
  min-width: 270px;
}

.control-group label {
  font-size: 12px;
  color: var(--muted);
  white-space: nowrap;
  text-transform: none;
}

.control-group-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 8px;
}

.control-group-sub {
  font-size: 11px;
  color: rgba(255,255,255,0.55);
}

.ratio-input-row {
  display: flex;
  align-items: center;
  gap: 10px;
}

.control-group input[type="number"] {
  width: 70px;
  padding: 7px 8px;
  border-radius: 8px;
  border: 1px solid var(--border-strong);
  background: rgba(255,255,255,0.08);
  color: white;
  outline: none;
  text-align: center;
  font-variant-numeric: tabular-nums;
}

.control-group input[type="range"] {
  flex: 1;
}

/* Ratio slider - match app aesthetic */
.control-group input[type="range"] {
  appearance: none;
  -webkit-appearance: none;
  height: 6px;
  border-radius: 999px;
  background: rgba(255,255,255,0.12);
  border: 1px solid rgba(255,255,255,0.18);
  outline: none;
  cursor: pointer;
}

.control-group input[type="range"]::-webkit-slider-runnable-track {
  height: 6px;
  border-radius: 999px;
  background: rgba(255,255,255,0.12);
}

.control-group input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 14px;
  height: 14px;
  margin-top: -5px;
  border-radius: 999px;
  background: #ffffff;
  border: 2px solid rgba(98,198,255,0.85);
  box-shadow:
    0 0 0 3px rgba(98,198,255,0.22),
    0 3px 8px rgba(0,0,0,0.35);
}

.control-group input[type="range"]::-moz-range-track {
  height: 6px;
  border-radius: 999px;
  background: rgba(255,255,255,0.12);
}

.control-group input[type="range"]::-moz-range-thumb {
  width: 14px;
  height: 14px;
  border-radius: 999px;
  background: #ffffff;
  border: 2px solid rgba(98,198,255,0.85);
  box-shadow:
    0 0 0 3px rgba(98,198,255,0.22),
    0 3px 8px rgba(0,0,0,0.35);
}

/* Hide native number spinners to keep clean look */
.control-group input[type="number"]::-webkit-outer-spin-button,
.control-group input[type="number"]::-webkit-inner-spin-button {
  appearance: none;
  -webkit-appearance: none;
  margin: 0;
}

.control-group input[type="number"] {
  -moz-appearance: textfield;
}

.btn,
.file-btn {
  appearance: none;
  border: 1px solid var(--border-strong);
  background: rgba(255,255,255,0.08);
  color: white;
  padding: 9px 12px;
  border-radius: 12px;
  font-size: 14px;
  cursor: pointer;
  transition: background 0.15s ease, transform 0.15s ease, opacity 0.15s ease, border-color 0.15s ease;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  max-width: 100%;
}

.btn:hover,
.file-btn:hover {
  background: rgba(255,255,255,0.14);
}

.btn:active,
.file-btn:active {
  transform: translateY(1px);
}

.btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.btn-primary {
  background: var(--accent-2);
  border-color: rgba(98, 198, 255, 0.45);
}

.btn-primary:hover {
  background: rgba(98, 198, 255, 0.28);
}

/* Simplify button states: idle (default), loading, success */
#btn-simplify .btn-simplify-spinner,
#btn-simplify .btn-simplify-tick {
  display: none;
}

#btn-simplify.btn-simplify-loading {
  pointer-events: none;
}

#btn-simplify.btn-simplify-loading .btn-simplify-label {
  display: none;
}

#btn-simplify.btn-simplify-loading .btn-simplify-spinner {
  display: inline-block;
  width: 16px;
  height: 16px;
  border: 2px solid rgba(255, 255, 255, 0.35);
  border-top-color: white;
  border-radius: 50%;
  animation: btn-simplify-spin 0.7s linear infinite;
}

@keyframes btn-simplify-spin {
  to {
    transform: rotate(360deg);
  }
}

#btn-simplify.btn-simplify-success .btn-simplify-label {
  display: none;
}

#btn-simplify.btn-simplify-success .btn-simplify-spinner {
  display: none;
}

#btn-simplify.btn-simplify-success .btn-simplify-tick {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  font-weight: 700;
  animation: btn-simplify-tick 0.35s ease-out;
}

@keyframes btn-simplify-tick {
  0% {
    transform: scale(0.5);
    opacity: 0;
  }
  60% {
    transform: scale(1.15);
    opacity: 1;
  }
  100% {
    transform: scale(1);
    opacity: 1;
  }
}

.hidden-input {
  display: none;
}

/* Overlay shown while loading original PLY (examples or local) */
#loading-overlay {
  position: absolute;
  inset: 0;
  z-index: 60;
  display: none;
  align-items: center;
  justify-content: center;
  pointer-events: none;
  background: radial-gradient(circle at center, rgba(15, 17, 21, 0.1), rgba(15, 17, 21, 0.85));
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

#loading-overlay.visible {
  display: flex;
}

.loading-overlay-spinner {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  border: 3px solid rgba(255, 255, 255, 0.3);
  border-top-color: rgba(255, 255, 255, 0.95);
  animation: loading-overlay-spin 0.7s linear infinite;
  margin-right: 12px;
}

.loading-overlay-text {
  font-size: 13px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.85);
}

@keyframes loading-overlay-spin {
  to {
    transform: rotate(360deg);
  }
}

#progress-panel {
  position: relative;
  width: 316px;
  height: 100%;
  z-index: 70;
  pointer-events: auto;
  flex: 0 0 316px;
  padding: 12px;
}

.panel-card {
  height: 100%;
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 14px;
  border-radius: 18px;
  background: var(--panel);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  pointer-events: auto;
}

.panel-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
}

.panel-title {
  font-size: 15px;
  font-weight: 700;
}

.badge {
  min-width: 48px;
  padding: 6px 8px;
  border-radius: 999px;
  background: rgba(255,255,255,0.07);
  border: 1px solid var(--border);
  text-align: center;
  font-size: 12px;
  font-weight: 700;
}

#progress-bar {
  height: 8px;
  border-radius: 999px;
  background: rgba(255,255,255,0.08);
  overflow: hidden;
  border: 1px solid rgba(255,255,255,0.06);
}

#progress-bar-fill {
  width: 0%;
  height: 100%;
  background: linear-gradient(90deg, rgba(98,198,255,0.45), rgba(98,198,255,0.95));
  transition: width 0.18s ease;
}

#stats-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.stat {
  padding: 10px 11px;
  border-radius: 12px;
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.07);
}

.stat-label {
  font-size: 11px;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.stat-value {
  margin-top: 4px;
  font-size: 16px;
  font-weight: 700;
}

#track-list {
  flex: 1;
  overflow: auto;
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding-right: 2px;
}

/* Track list custom scrollbar */
#track-list::-webkit-scrollbar {
  width: 6px;
}

#track-list::-webkit-scrollbar-track {
  background: transparent;
}

#track-list::-webkit-scrollbar-thumb {
  border-radius: 999px;
  background: rgba(255,255,255,0.18);
  box-shadow: 0 0 0 1px rgba(0,0,0,0.35);
}

#track-list::-webkit-scrollbar-thumb:hover {
  background: rgba(255,255,255,0.28);
}

.track-item-wrap {
  display: flex;
  align-items: stretch;
  gap: 6px;
}

.track-item-wrap .track-item {
  flex: 1;
  min-width: 0;
}

.track-download {
  flex-shrink: 0;
  width: 36px;
  padding: 0;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: rgba(255,255,255,0.06);
  color: var(--muted);
  font-size: 14px;
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.track-download:hover {
  background: rgba(98,198,255,0.18);
  color: var(--accent);
  border-color: rgba(98,198,255,0.35);
}

.track-item {
  width: 100%;
  text-align: left;
  padding: 11px 12px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: rgba(255,255,255,0.05);
  color: white;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease, transform 0.15s ease;
}

.track-item:hover {
  background: rgba(255,255,255,0.10);
}

.track-item.active {
  background: rgba(98,198,255,0.14);
  border-color: rgba(98,198,255,0.42);
}

.track-row-top {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: center;
}

.track-title {
  font-size: 13px;
  font-weight: 700;
}

.track-count {
  font-size: 12px;
  color: var(--muted);
}

.track-row-bottom {
  margin-top: 6px;
  font-size: 12px;
  color: var(--muted);
}

@media (max-width: 1380px) {
  #app {
    flex-direction: column;
  }

  #progress-panel {
    width: auto;
    flex: 0 0 auto;
    height: 320px;
    padding: 12px;
  }

  .panel-card {
    max-height: 320px;
  }
}

@media (max-width: 1200px) {
}
#progress-bar {
  position: relative;
  height: 10px;
  border-radius: 999px;
  background: rgba(255,255,255,0.08);
  overflow: visible;
  border: 1px solid rgba(255,255,255,0.06);
  cursor: pointer;
  touch-action: none;
}

#progress-bar-fill {
  width: 0%;
  height: 100%;
  border-radius: 999px;
  background: linear-gradient(90deg, rgba(98,198,255,0.45), rgba(98,198,255,0.95));
  transition: width 0.12s ease;
}

#progress-bar-handle {
  position: absolute;
  top: 50%;
  left: 0%;
  width: 16px;
  height: 16px;
  transform: translate(-50%, -50%);
  border-radius: 999px;
  background: #ffffff;
  border: 2px solid rgba(98,198,255,0.85);
  box-shadow:
    0 0 0 4px rgba(98,198,255,0.18),
    0 4px 10px rgba(0,0,0,0.30);
  transition: left 0.12s ease;
  pointer-events: none;
}