:root {
  --bg: #f7f8fb;
  --ink: #172033;
  --muted: #667085;
  --line: #d9e0ea;
  --panel: #ffffff;
  --blue: #2f6fed;
  --green: #10a66a;
  --orange: #f97316;
  --yellow: #facc15;
  --red: #d92d20;
  --wire: #2d3748;
  --shadow: 0 18px 50px rgba(23, 32, 51, 0.12);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  font-family:
    system-ui,
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    sans-serif;
  background:
    radial-gradient(circle at 12% 8%, rgba(47, 111, 237, 0.14), transparent 28rem),
    linear-gradient(135deg, #f7f8fb 0%, #eef5f1 100%);
}

button,
select {
  font: inherit;
}

button {
  cursor: pointer;
}

button:disabled {
  opacity: 0.46;
  cursor: not-allowed;
}

.app {
  min-height: 100vh;
  padding: 24px;
}

.workspace {
  width: min(1540px, 100%);
  min-height: calc(100vh - 48px);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.topbar {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 18px;
}

.eyebrow {
  margin: 0 0 5px;
  color: var(--blue);
  font-weight: 700;
  font-size: 0.82rem;
}

h1,
h2,
h3 {
  margin: 0;
  line-height: 1.1;
}

h1 {
  font-size: clamp(1.6rem, 3vw, 2.7rem);
}

h2 {
  font-size: 1.1rem;
}

h3 {
  font-size: 1rem;
}

.baseline {
  max-width: 360px;
  display: grid;
  gap: 3px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.82);
  box-shadow: 0 10px 28px rgba(23, 32, 51, 0.08);
}

.baseline strong {
  color: var(--blue);
}

.baseline span {
  color: var(--muted);
  font-weight: 700;
  font-size: 0.88rem;
}

.layout {
  flex: 1;
  display: grid;
  grid-template-columns: minmax(760px, 1fr) 300px;
  grid-template-areas:
    "circuit parts"
    "circuit results";
  align-items: start;
  gap: 16px;
}

.parts-panel,
.results-panel,
.circuit-panel {
  min-width: 0;
}

.parts-panel,
.results-panel {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 18px;
  background: rgba(255, 255, 255, 0.92);
  box-shadow: var(--shadow);
}

.parts-panel {
  grid-area: parts;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.template-panel {
  display: grid;
  gap: 10px;
  padding-top: 6px;
}

.preset-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
}

.part {
  width: 100%;
  min-height: 82px;
  display: flex;
  align-items: center;
  gap: 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 12px;
  text-align: left;
  color: var(--ink);
  background: white;
  cursor: grab;
  touch-action: none;
  user-select: none;
}

.part:active {
  cursor: grabbing;
}

.part:disabled,
.part:disabled:active {
  cursor: not-allowed;
  background: #f3f5f8;
}

.part strong,
.part small {
  display: block;
}

.part small {
  margin-top: 4px;
  color: var(--muted);
  font-size: 0.78rem;
}

.battery-icon {
  position: relative;
  width: 50px;
  height: 28px;
  flex: 0 0 auto;
  border: 3px solid #2a3242;
  border-radius: 5px;
  background: linear-gradient(90deg, var(--green) 0 62%, #e8eef6 62%);
}

.battery-icon::after {
  content: "";
  position: absolute;
  top: 7px;
  right: -8px;
  width: 6px;
  height: 12px;
  border-radius: 0 3px 3px 0;
  background: #2a3242;
}

.bulb-icon {
  position: relative;
  width: 40px;
  height: 40px;
  flex: 0 0 auto;
  border: 3px solid #2a3242;
  border-radius: 50%;
  background: #fff7c2;
  box-shadow: 0 0 calc(3px + var(--current-glow, 0.3) * 14px) rgba(250, 204, 21, 0.22);
}

.bulb-icon::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: -13px;
  transform: translateX(-50%);
  width: 14px;
  height: 13px;
  border: 3px solid #2a3242;
  border-top: 0;
  border-radius: 0 0 4px 4px;
  background: #b9c2cf;
}

.bulb-icon.lit {
  --current-glow: 0.9;
}

.ammeter-icon {
  width: 42px;
  height: 42px;
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  border: 3px solid #2a3242;
  border-radius: 50%;
  color: var(--blue);
  background: white;
  font-weight: 900;
}

.wire-icon {
  position: relative;
  width: 54px;
  height: 34px;
  flex: 0 0 auto;
}

.wire-icon::before {
  content: "";
  position: absolute;
  left: 3px;
  right: 3px;
  top: 15px;
  height: 6px;
  border-radius: 99px;
  background: var(--wire);
}

.parallel-icon {
  position: relative;
  width: 54px;
  height: 42px;
  flex: 0 0 auto;
}

.parallel-icon::before,
.parallel-icon::after {
  content: "";
  position: absolute;
  left: 8px;
  right: 8px;
  height: 9px;
  border: 3px solid var(--wire);
  border-left-width: 6px;
  border-right-width: 6px;
  border-radius: 99px;
}

.parallel-icon::before {
  top: 7px;
}

.parallel-icon::after {
  bottom: 7px;
}

.parallel-icon.direct::before {
  top: 3px;
}

.parallel-icon.direct::after {
  bottom: 3px;
}

.mini-controls {
  margin-top: auto;
  display: grid;
  gap: 12px;
}

.preset-group {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 8px;
}

.preset-group span {
  grid-column: 1 / -1;
  color: var(--muted);
  font-size: 0.84rem;
  font-weight: 700;
}

.preset-button {
  flex: 0 0 auto;
  min-height: 42px;
  border: 1px solid rgba(47, 111, 237, 0.26);
  border-radius: 6px;
  padding: 7px 8px;
  color: var(--blue);
  background: rgba(47, 111, 237, 0.07);
  font-size: 0.86rem;
  font-weight: 800;
  line-height: 1.18;
  white-space: normal;
}

.preset-button.compact {
  min-height: 42px;
}

.preset-button:hover,
.small-action:hover,
.ghost-button:hover {
  background: rgba(47, 111, 237, 0.14);
}

.preset-button:disabled:hover,
.small-action:disabled:hover,
.ghost-button:disabled:hover {
  background: rgba(47, 111, 237, 0.08);
}

.mini-controls label {
  color: var(--muted);
  font-size: 0.84rem;
  font-weight: 700;
}

select {
  width: 100%;
  margin-top: 6px;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: white;
  color: var(--ink);
}

.ghost-button,
.small-action {
  border-radius: 6px;
  font-weight: 800;
}

.ghost-button {
  padding: 11px 14px;
  color: var(--blue);
  border: 1px solid rgba(47, 111, 237, 0.3);
  background: rgba(47, 111, 237, 0.08);
}

.small-action {
  flex: 0 0 auto;
  min-height: 30px;
  padding: 6px 10px;
  color: var(--blue);
  border: 1px solid rgba(47, 111, 237, 0.28);
  background: rgba(47, 111, 237, 0.08);
  white-space: nowrap;
}

.small-action.danger {
  color: var(--red);
  border-color: rgba(217, 45, 32, 0.28);
  background: rgba(217, 45, 32, 0.07);
}

.free-tool.selected {
  color: white;
  border-color: var(--blue);
  background: var(--blue);
}

.free-tool.selected.danger {
  border-color: var(--red);
  background: var(--red);
}

.circuit-panel {
  grid-area: circuit;
  display: flex;
}

.drop-zone {
  flex: 1;
  min-height: 650px;
  overflow: auto;
  border: 2px dashed #bcc8d8;
  border-radius: 8px;
  background:
    linear-gradient(90deg, rgba(23, 32, 51, 0.06) 1px, transparent 1px),
    linear-gradient(rgba(23, 32, 51, 0.06) 1px, transparent 1px),
    rgba(255, 255, 255, 0.74);
  background-size: 32px 32px;
  box-shadow: var(--shadow);
}

.drop-zone.drag-over {
  border-color: var(--blue);
  background-color: rgba(47, 111, 237, 0.08);
}

.circuit-board {
  min-width: 780px;
  min-height: 100%;
  padding: 18px;
  display: grid;
  grid-template-rows: 1fr;
}

.schematic-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  overflow-x: visible;
  padding-bottom: 4px;
}

.toolbar-label {
  color: var(--muted);
  font-size: 0.84rem;
  font-weight: 900;
}

.toolbar-divider {
  width: 1px;
  height: 28px;
  background: var(--line);
}

.schematic {
  width: max(100%, var(--schematic-width, 100%));
  min-height: 560px;
  border: 1px solid rgba(23, 32, 51, 0.1);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.9);
  box-shadow: 0 12px 34px rgba(23, 32, 51, 0.1);
  touch-action: none;
}

.wire {
  stroke: var(--wire);
  stroke-width: 8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.filament {
  stroke: #2a3242;
  stroke-width: 3;
  stroke-linecap: round;
}

.value-badge rect {
  fill: rgba(255, 255, 255, 0.94);
  stroke: rgba(23, 32, 51, 0.12);
  stroke-width: 1;
}

.current-badge rect {
  fill: #ffffff;
  stroke: rgba(47, 111, 237, 0.3);
  stroke-width: 1.5;
}

.bulb-glass {
  fill: #fff7c2;
  stroke: #2a3242;
  stroke-width: 4;
  filter: none;
}

.battery-long,
.battery-short {
  stroke: #2a3242;
  stroke-width: 7;
  stroke-linecap: round;
}

.battery-long {
  stroke: var(--green);
}

.battery-bank-box {
  fill: rgba(255, 255, 255, 0.96);
  stroke: #2a3242;
  stroke-width: 4;
}

.battery-pack-long,
.battery-pack-short {
  stroke: #2a3242;
  stroke-linecap: round;
}

.battery-pack-long {
  stroke: var(--green);
  stroke-width: 6;
}

.battery-pack-short {
  stroke-width: 5;
}

.ammeter-face {
  fill: white;
  stroke: #2a3242;
  stroke-width: 4;
}

.wire-leaf {
  stroke: var(--wire);
  stroke-width: 10;
  stroke-linecap: round;
}

.short-warning {
  fill: rgba(217, 45, 32, 0.08);
  stroke: rgba(217, 45, 32, 0.3);
  stroke-width: 2;
}

.svg-label {
  fill: var(--ink);
  font-size: 17px;
  font-weight: 800;
}

.svg-small {
  fill: #475467;
  font-size: 14px;
  font-weight: 800;
}

.svg-note {
  fill: var(--blue);
  font-size: 16px;
  font-weight: 900;
}

.svg-warning {
  fill: var(--red);
  font-size: 16px;
  font-weight: 900;
}

.terminal-label {
  fill: var(--green);
  font-size: 22px;
  font-weight: 900;
}

.free-layer .wire {
  stroke-width: 7;
}

.free-node {
  cursor: pointer;
  outline: none;
}

.free-node circle {
  fill: white;
  stroke: var(--blue);
  stroke-width: 3;
}

.free-node:hover circle,
.free-node:focus circle,
.free-node.selected circle {
  fill: rgba(47, 111, 237, 0.16);
  stroke-width: 5;
}

.free-component {
  cursor: pointer;
}

.free-wire-edge:hover .wire,
.free-wire-edge:focus .wire {
  stroke: var(--blue);
}

.svg-button {
  outline: none;
}

.svg-button rect {
  fill: rgba(47, 111, 237, 0.1);
  stroke: rgba(47, 111, 237, 0.35);
  stroke-width: 1.5;
}

.svg-button.danger rect {
  fill: rgba(217, 45, 32, 0.09);
  stroke: rgba(217, 45, 32, 0.35);
}

.svg-button:hover rect,
.svg-button:focus rect {
  fill: rgba(47, 111, 237, 0.2);
}

.svg-button.danger:hover rect,
.svg-button.danger:focus rect {
  fill: rgba(217, 45, 32, 0.18);
}

.svg-button-text {
  pointer-events: none;
  fill: var(--blue);
  font-size: 14px;
  font-weight: 900;
}

.svg-button.danger .svg-button-text {
  fill: var(--red);
}

.drag-item {
  cursor: grab;
  outline: none;
  touch-action: none;
}

.drag-item:active {
  cursor: grabbing;
}

.drag-ghost {
  opacity: 0.72;
  pointer-events: none;
}

.drag-ghost.delete {
  opacity: 0.55;
}

.drag-ghost.delete .bulb-glass,
.drag-ghost.delete .battery-bank-box {
  stroke: var(--red);
}

.drop-sensor {
  fill: transparent;
  pointer-events: none;
}

.drop-sensor.active {
  fill: rgba(47, 111, 237, 0.16);
  stroke: rgba(47, 111, 237, 0.45);
  stroke-width: 2;
  stroke-dasharray: 8 6;
}

.drop-preview {
  pointer-events: none;
}

.drop-preview-box {
  fill: rgba(47, 111, 237, 0.12);
  stroke: var(--blue);
  stroke-width: 3;
  stroke-dasharray: 10 7;
}

.drop-preview.parallel .drop-preview-box {
  fill: rgba(16, 166, 106, 0.12);
  stroke: var(--green);
}

.drop-preview-line {
  stroke: var(--blue);
  stroke-width: 5;
  stroke-linecap: round;
  stroke-dasharray: 10 7;
}

.drop-preview.parallel .drop-preview-line {
  stroke: var(--green);
}

.drop-preview-label-bg {
  fill: white;
  stroke: rgba(47, 111, 237, 0.3);
  stroke-width: 1.5;
}

.drop-preview.parallel .drop-preview-label-bg {
  stroke: rgba(16, 166, 106, 0.35);
}

.drop-preview-label {
  fill: var(--blue);
  font-size: 15px;
  font-weight: 900;
}

.drop-preview.parallel .drop-preview-label {
  fill: var(--green);
}

.delete-zone.active {
  fill: rgba(217, 45, 32, 0.08);
  stroke: rgba(217, 45, 32, 0.32);
  stroke-width: 2;
  stroke-dasharray: 9 7;
}

.results-panel {
  grid-area: results;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.meters {
  display: grid;
  gap: 12px;
}

.meter {
  display: grid;
  grid-template-columns: 1fr auto auto;
  align-items: baseline;
  gap: 4px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

.meter span {
  color: var(--muted);
  font-weight: 700;
  font-size: 0.84rem;
}

.meter strong {
  font-size: 1.4rem;
}

.meter small {
  color: var(--muted);
  font-weight: 700;
}

.bar {
  grid-column: 1 / -1;
  height: 9px;
  overflow: hidden;
  border-radius: 99px;
  background: #e6ebf2;
}

.bar i {
  display: block;
  width: 0%;
  height: 100%;
  border-radius: inherit;
  background: var(--blue);
  transition: width 180ms ease;
}

.bar.life i {
  background: var(--green);
}

.readout,
.explain {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 14px;
  background: #fbfcff;
}

.detail-list {
  max-height: 240px;
  overflow: auto;
  display: grid;
  gap: 8px;
  margin-top: 10px;
  padding-right: 4px;
}

.compact-list {
  max-height: none;
}

.detail-row {
  display: grid;
  gap: 4px;
  padding: 9px 0;
  border-bottom: 1px solid #edf1f6;
}

.detail-row:last-child {
  border-bottom: 0;
}

.detail-row span {
  color: var(--muted);
  font-weight: 800;
  font-size: 0.8rem;
}

.detail-row strong {
  font-size: 0.86rem;
  line-height: 1.45;
  overflow-wrap: anywhere;
}

.explain {
  color: #344054;
  font-size: 0.9rem;
  line-height: 1.65;
}

.explain strong {
  color: var(--ink);
}

@media (max-width: 1180px) {
  .layout {
    grid-template-columns: minmax(560px, 1fr) 260px;
    grid-template-areas:
      "circuit parts"
      "circuit results";
  }
}

@media (max-width: 760px) {
  .app {
    padding: 14px;
  }

  .topbar,
  .layout {
    display: grid;
  }

  .layout {
    grid-template-columns: 1fr;
    grid-template-areas:
      "circuit"
      "parts"
      "results";
  }

  .circuit-panel {
    order: 1;
  }

  .parts-panel {
    order: 2;
  }

  .results-panel {
    order: 3;
  }

  .drop-zone {
    min-height: 520px;
  }

  .circuit-board {
    min-width: 0;
    padding: 12px;
  }

  .schematic {
    min-height: 430px;
  }
}