:root {
  color-scheme: dark;
  --bg: #111417;
  --panel: #181d22;
  --panel-soft: #20262d;
  --line: #2e3740;
  --text: #edf2f7;
  --muted: #aeb8c4;
  --accent: #5fc6c7;
  --accent-2: #f0b85a;
  --danger: #eb6f6f;
  --soft-divider: rgba(255, 255, 255, 0.08);
  --tile-detail: rgba(237, 242, 247, 0.78);
  --shell-stroke: rgba(237, 242, 247, 0.2);
  --canvas-grid: rgba(255, 255, 255, 0.035);
  --canvas-bg: #101418;
  --shadow: 0 18px 45px rgba(0, 0, 0, 0.28);
  font-family: Inter, Segoe UI, system-ui, -apple-system, sans-serif;
}

body[data-theme="light"] {
  color-scheme: light;
  --bg: #eef3f5;
  --panel: #ffffff;
  --panel-soft: #e8eef2;
  --line: #c9d5dc;
  --text: #172129;
  --muted: #5f6f7a;
  --accent: #227b82;
  --accent-2: #a86312;
  --danger: #b84545;
  --soft-divider: rgba(23, 33, 41, 0.1);
  --tile-detail: rgba(23, 33, 41, 0.68);
  --shell-stroke: rgba(23, 33, 41, 0.22);
  --canvas-grid: rgba(23, 33, 41, 0.055);
  --canvas-bg: #f9fcfd;
  --shadow: 0 16px 36px rgba(32, 48, 56, 0.14);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-width: 1120px;
  background: radial-gradient(circle at top left, rgba(95, 198, 199, 0.12), transparent 32rem), var(--bg);
  color: var(--text);
}

body[data-theme="light"] {
  background: radial-gradient(circle at top left, rgba(34, 123, 130, 0.12), transparent 32rem), var(--bg);
}

.app {
  min-height: 100vh;
  padding: 22px;
}

.topbar {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 16px;
}

h1,
h2,
p {
  margin: 0;
}

h1 {
  font-size: 28px;
  font-weight: 760;
}

h2 {
  font-size: 17px;
  font-weight: 720;
}

.topbar p {
  margin-top: 6px;
  color: var(--muted);
}

.top-actions {
  display: flex;
  align-items: end;
  gap: 12px;
}

.search {
  display: grid;
  gap: 7px;
  color: var(--muted);
  font-size: 13px;
}

.search input {
  width: 300px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  color: var(--text);
  padding: 11px 13px;
  outline: none;
}

.search input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 22%, transparent);
}

.theme-toggle {
  min-height: 42px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  color: var(--text);
  cursor: pointer;
  font-weight: 700;
  padding: 0 14px;
}

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

.periodic-wrap {
  overflow-x: auto;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: rgba(24, 29, 34, 0.82);
  box-shadow: var(--shadow);
}

body[data-theme="light"] .periodic-wrap,
body[data-theme="light"] .element-list-panel,
body[data-theme="light"] .atom-panel,
body[data-theme="light"] .params-panel,
body[data-theme="light"] .wiki-panel {
  background: rgba(255, 255, 255, 0.9);
}

body[data-theme="light"] .periodic-wrap {
  background: rgba(255, 255, 255, 0.78);
}

.legend-wrap {
  display: flex;
  align-items: center;
  gap: 14px;
  width: max-content;
  margin-top: 13px;
  padding-top: 12px;
  border-top: 1px solid var(--soft-divider);
}

.legend-wrap h2 {
  color: var(--muted);
  font-size: 13px;
  text-transform: uppercase;
}

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 12px;
  max-width: 1120px;
}

.legend-item {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  color: var(--muted);
  font-size: 12px;
  white-space: nowrap;
}

.legend-swatch {
  width: 14px;
  height: 14px;
  border: 1px solid var(--line);
  border-radius: 4px;
}

.periodic-table {
  display: grid;
  grid-template-columns: repeat(18, 64px);
  grid-template-rows: repeat(9, 58px);
  gap: 5px;
  width: max-content;
}

.tile {
  position: relative;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel-soft);
  color: var(--text);
  cursor: pointer;
  padding: 5px;
  text-align: left;
  transition: transform 150ms ease, border-color 150ms ease, background 150ms ease;
}

.tile:hover,
.tile.active {
  transform: translateY(-2px);
  border-color: var(--accent);
  background: #24313a;
}

body[data-theme="light"] .tile:hover,
body[data-theme="light"] .tile.active {
  background: #dce9ee;
}

.tile.filtered-out {
  opacity: 0.22;
}

.atomic-number {
  font-size: 10px;
  color: var(--tile-detail);
}

.tile-symbol {
  display: block;
  margin-top: 2px;
  font-size: 20px;
  font-weight: 800;
  line-height: 1;
}

.tile-name {
  display: block;
  margin-top: 3px;
  overflow: hidden;
  color: var(--tile-detail);
  font-size: 10px;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.workspace {
  display: grid;
  grid-template-columns: 260px minmax(360px, 1fr) 310px 390px;
  gap: 16px;
  margin-top: 16px;
  align-items: stretch;
}

.element-list-panel,
.atom-panel,
.params-panel,
.wiki-panel {
  min-height: 620px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: rgba(24, 29, 34, 0.9);
  box-shadow: var(--shadow);
}

.element-list-panel,
.params-panel,
.wiki-panel {
  padding: 14px;
}

.panel-title,
.wiki-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

#countLabel,
.wiki-header a {
  color: var(--accent);
  font-size: 13px;
}

.element-list {
  display: grid;
  gap: 7px;
  max-height: 565px;
  margin-top: 13px;
  overflow: auto;
  padding-right: 4px;
}

.list-item {
  display: grid;
  grid-template-columns: 34px 1fr auto;
  align-items: center;
  gap: 9px;
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #151a1f;
  color: var(--text);
  cursor: pointer;
  padding: 9px;
  text-align: left;
}

body[data-theme="light"] .list-item {
  background: #f8fbfc;
}

.list-item.active {
  border-color: var(--accent);
  background: #213039;
}

body[data-theme="light"] .list-item.active {
  background: #dce9ee;
}

.list-symbol {
  display: grid;
  width: 34px;
  height: 34px;
  place-items: center;
  border-radius: 7px;
  background: var(--panel-soft);
  font-weight: 800;
}

.list-name {
  display: block;
  font-size: 14px;
  font-weight: 680;
}

.list-meta {
  display: block;
  margin-top: 2px;
  color: var(--muted);
  font-size: 11px;
}

.atom-panel {
  display: grid;
  grid-template-rows: auto 1fr auto auto auto;
  gap: 14px;
  padding: 16px;
}

.selected-heading {
  display: flex;
  align-items: center;
  gap: 13px;
}

.symbol-badge {
  display: grid;
  width: 58px;
  height: 58px;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--accent);
  color: #0d1215;
  font-size: 29px;
  font-weight: 840;
}

#elementSubtitle {
  margin-top: 4px;
  color: var(--muted);
}

.atom-canvas {
  position: relative;
  min-height: 430px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 10px;
  background:
    linear-gradient(var(--canvas-grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--canvas-grid) 1px, transparent 1px),
    var(--canvas-bg);
  background-size: 24px 24px;
}

.atom-svg {
  width: 100%;
  height: 100%;
  min-height: 430px;
  display: block;
}

.shell-line {
  fill: none;
  stroke: var(--shell-stroke);
  stroke-width: 1.4;
}

.electron {
  fill: #72d4ff;
  filter: drop-shadow(0 0 6px rgba(114, 212, 255, 0.72));
}

.nucleus-ring {
  fill: rgba(240, 184, 90, 0.12);
  stroke: rgba(240, 184, 90, 0.52);
}

.nucleus-label {
  fill: var(--text);
  font-size: 14px;
  font-weight: 800;
}

body[data-theme="light"] .nucleus-label {
  fill: #172129;
}

.scale-ruler line {
  stroke: var(--muted);
  stroke-linecap: round;
  stroke-width: 2;
}

.scale-ruler text {
  fill: var(--muted);
  font-size: 12px;
  font-weight: 700;
}

.proton {
  fill: #f06b65;
}

.neutron {
  fill: #d6c9a8;
}

.atom-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 12px;
  align-items: center;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: color-mix(in srgb, var(--panel-soft) 72%, transparent);
  padding: 10px;
}

.atom-legend-item {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  color: var(--muted);
  font-size: 12px;
  white-space: nowrap;
}

.atom-legend-dot,
.atom-legend-ring {
  display: inline-block;
  width: 14px;
  height: 14px;
  flex: 0 0 auto;
}

.atom-legend-dot {
  border-radius: 50%;
}

.electron-dot {
  background: #72d4ff;
  box-shadow: 0 0 8px rgba(114, 212, 255, 0.72);
}

.proton-dot {
  background: #f06b65;
}

.neutron-dot {
  background: #d6c9a8;
}

.shell-dot {
  border: 2px solid var(--shell-stroke);
  border-radius: 50%;
}

.nucleus-dot {
  border: 2px solid rgba(240, 184, 90, 0.62);
  border-radius: 50%;
  background: rgba(240, 184, 90, 0.12);
}

.shell-info {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(80px, 1fr));
  gap: 8px;
}

.shell-pill {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #141a1f;
  padding: 9px;
  text-align: center;
}

body[data-theme="light"] .shell-pill {
  background: #f8fbfc;
}

.shell-pill strong {
  display: block;
  color: var(--accent-2);
  font-size: 17px;
}

.shell-pill span {
  color: var(--muted);
  font-size: 11px;
}

.subshell-panel {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: color-mix(in srgb, var(--panel-soft) 62%, transparent);
  padding: 10px;
}

.subshell-panel h3 {
  margin: 0 0 8px;
  color: var(--muted);
  font-size: 12px;
  text-transform: uppercase;
}

.subshell-info {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
  max-height: 92px;
  overflow: auto;
}

.subshell-pill {
  display: inline-flex;
  align-items: baseline;
  gap: 5px;
  border: 1px solid var(--line);
  border-radius: 7px;
  background: var(--panel);
  padding: 6px 8px;
  white-space: nowrap;
}

.subshell-pill strong {
  color: var(--text);
  font-size: 13px;
}

.subshell-pill span {
  color: var(--muted);
  font-size: 10px;
}

.params-list {
  display: grid;
  gap: 8px;
  margin: 14px 0 0;
}

.params-list div {
  display: grid;
  grid-template-columns: 112px 1fr;
  gap: 9px;
  border-bottom: 1px solid var(--soft-divider);
  padding: 7px 0;
}

.params-list dt {
  color: var(--muted);
  font-size: 12px;
}

.params-list dd {
  margin: 0;
  color: var(--text);
  font-size: 13px;
  overflow-wrap: anywhere;
}

.wiki-panel {
  display: grid;
  grid-template-rows: auto 1fr;
  gap: 12px;
}

.wiki-panel iframe {
  width: 100%;
  height: 100%;
  min-height: 560px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

@media (max-width: 1300px) {
  body {
    min-width: 960px;
  }

  .workspace {
    grid-template-columns: 250px minmax(340px, 1fr) 300px;
  }

  .wiki-panel {
    grid-column: 1 / -1;
    min-height: 460px;
  }

  .wiki-panel iframe {
    min-height: 400px;
  }
}