:root {
  --ink: #101828;
  --muted: #526071;
  --line: #d6dee8;
  --soft: #f3f6f9;
  --paper: #ffffff;
  --blue: #1769e0;
  --blue-dark: #0c4cab;
  --green: #138a3d;
  --purple: #7e22ce;
  --orange: #f97316;
  --red: #d62828;
  --radius: 18px;
  --shadow: 0 18px 50px rgba(16, 24, 40, 0.09);
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: 88px;
}

body {
  margin: 0;
  color: var(--ink);
  background: #f8fafc;
  font-family: "Malgun Gothic", "Apple SD Gothic Neo", Arial, sans-serif;
  line-height: 1.55;
}

a { color: inherit; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 72px;
  padding: 12px clamp(20px, 4vw, 64px);
  border-bottom: 1px solid rgba(214, 222, 232, 0.9);
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(14px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  font-size: 16px;
  font-weight: 900;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  width: 38px;
  height: 38px;
  place-items: center;
  border-radius: 10px;
  color: #fff;
  background: var(--ink);
  font-size: 13px;
  letter-spacing: 0.04em;
}

nav {
  display: flex;
  gap: clamp(14px, 2vw, 28px);
  font-size: 14px;
  font-weight: 800;
}

nav a {
  padding: 8px 0;
  color: #344054;
  text-decoration: none;
}

nav a:hover { color: var(--blue); }

main {
  width: min(1560px, calc(100% - 40px));
  margin: 0 auto;
}

.hero {
  display: grid;
  grid-template-columns: minmax(400px, 0.82fr) minmax(520px, 1.18fr);
  align-items: center;
  gap: clamp(34px, 5vw, 84px);
  min-height: 690px;
  padding: 72px 0 76px;
}

.hero-copy h1 {
  margin: 0;
  font-size: clamp(40px, 4.5vw, 74px);
  line-height: 1.12;
  letter-spacing: -0.045em;
}

.hero-copy > p {
  max-width: 650px;
  margin: 26px 0 0;
  color: var(--muted);
  font-size: clamp(17px, 1.35vw, 22px);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 20px;
  border: 1px solid var(--ink);
  border-radius: 11px;
  font-size: 14px;
  font-weight: 900;
  text-decoration: none;
  transition: transform 150ms ease, box-shadow 150ms ease, background 150ms ease;
}

.button:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 24px rgba(16, 24, 40, 0.13);
}

.button.primary { color: #fff; background: var(--ink); }
.button.secondary { background: #fff; }

.hero-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 26px 36px;
  margin: 38px 0 0;
}

.hero-stats div { display: grid; gap: 2px; }
.hero-stats dt { color: #667085; font-size: 12px; font-weight: 800; }
.hero-stats dd { margin: 0; font-size: 15px; font-weight: 900; }

.hero-preview {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 22px;
  background: #fff;
  box-shadow: var(--shadow);
  transform: rotate(0.8deg);
}

.hero-preview img {
  display: block;
  width: 100%;
  aspect-ratio: 8 / 5;
  object-fit: cover;
}

.rules {
  display: grid;
  grid-template-columns: minmax(260px, 0.65fr) minmax(520px, 1.35fr);
  gap: 48px;
  padding: 42px 46px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}

.rules h2,
.section-heading h2,
.connection-summary h2 {
  margin: 0;
  font-size: clamp(26px, 2.2vw, 36px);
  letter-spacing: -0.025em;
}

.rules p,
.section-heading p,
.connection-summary > div > p {
  margin: 8px 0 0;
  color: var(--muted);
}

.rules ul {
  display: grid;
  grid-template-columns: repeat(2, minmax(220px, 1fr));
  gap: 18px 28px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.rules li {
  display: flex;
  align-items: center;
  gap: 12px;
  min-height: 34px;
  font-size: 14px;
  font-weight: 850;
}

.rule-dot {
  width: 15px;
  height: 15px;
  flex: 0 0 auto;
  border: 3px solid #fff;
  border-radius: 50%;
  box-shadow: 0 0 0 1.5px #344054;
}

.rule-dot.green { background: var(--green); }
.rule-dot.purple { background: var(--purple); }

.rule-cross,
.rule-layers {
  position: relative;
  width: 27px;
  height: 23px;
  flex: 0 0 auto;
}

.rule-cross::before,
.rule-cross::after {
  position: absolute;
  content: "";
  background: #344054;
}

.rule-cross::before { top: 10px; left: 1px; width: 25px; height: 2px; }
.rule-cross::after { top: 1px; left: 12px; width: 2px; height: 21px; }

.rule-layers::before,
.rule-layers::after {
  position: absolute;
  left: 2px;
  width: 22px;
  height: 6px;
  border: 1px solid #344054;
  border-radius: 2px;
  background: #fff;
  content: "";
}

.rule-layers::before { top: 3px; box-shadow: 3px 5px 0 #cbd5e1; }
.rule-layers::after { top: 14px; background: var(--blue); }

.layouts { padding: 112px 0 90px; }

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 28px;
  margin-bottom: 30px;
}

.filters {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 8px;
}

.filter {
  min-height: 38px;
  padding: 0 14px;
  border: 1px solid var(--line);
  border-radius: 10px;
  color: #475467;
  background: #fff;
  font-family: inherit;
  font-size: 13px;
  font-weight: 850;
  cursor: pointer;
}

.filter:hover,
.filter.is-active {
  border-color: var(--ink);
  color: #fff;
  background: var(--ink);
}

.layout-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px;
}

.layout-card {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  box-shadow: 0 8px 24px rgba(16, 24, 40, 0.04);
  transition: opacity 180ms ease, transform 180ms ease, box-shadow 180ms ease;
}

.layout-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow);
}

.layout-card.is-hidden { display: none; }

.card-copy {
  display: flex;
  align-items: start;
  gap: 16px;
  min-height: 96px;
  padding: 22px 22px 18px;
}

.number {
  color: #98a2b3;
  font-size: 13px;
  font-weight: 900;
  letter-spacing: 0.08em;
}

.card-copy h3 {
  margin: 0;
  font-size: 19px;
  letter-spacing: -0.015em;
}

.card-copy p {
  margin: 5px 0 0;
  color: var(--muted);
  font-size: 13px;
}

.diagram-open {
  display: block;
  width: 100%;
  padding: 0;
  border: 0;
  border-top: 1px solid #e7ecf2;
  border-bottom: 1px solid #e7ecf2;
  background: var(--soft);
  cursor: zoom-in;
}

.diagram-open img {
  display: block;
  width: 100%;
  aspect-ratio: 8 / 5;
  object-fit: contain;
  background: #f8fafc;
}

.card-actions {
  display: flex;
  justify-content: flex-end;
  gap: 8px;
  padding: 13px 16px;
}

.card-actions a {
  min-width: 54px;
  padding: 6px 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: #344054;
  background: #fff;
  font-size: 12px;
  font-weight: 900;
  text-align: center;
  text-decoration: none;
}

.card-actions a:hover {
  border-color: var(--blue);
  color: var(--blue);
}

.connection-summary {
  display: grid;
  grid-template-columns: minmax(260px, 0.55fr) minmax(560px, 1.45fr);
  gap: 52px;
  margin-bottom: 100px;
  padding: 48px;
  border-radius: var(--radius);
  color: #fff;
  background: var(--ink);
}

.connection-summary > div > p { color: #b8c2d1; }

.signal-paths {
  display: grid;
  gap: 13px;
}

.signal-paths p {
  margin: 0;
  padding-bottom: 13px;
  border-bottom: 1px solid #344054;
  color: #e4e7ec;
  font-size: 14px;
}

.signal-paths p:last-child { padding-bottom: 0; border-bottom: 0; }
.signal-paths strong { display: inline-block; width: 55px; color: #fff; }

footer {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  padding: 25px clamp(20px, 4vw, 64px);
  border-top: 1px solid var(--line);
  color: #667085;
  background: #fff;
  font-size: 12px;
}

footer p { margin: 0; }
footer a { font-weight: 850; }

.viewer {
  width: min(98vw, 1900px);
  height: min(96vh, 1180px);
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: #fff;
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.3);
}

.viewer::backdrop { background: rgba(16, 24, 40, 0.72); }

.viewer-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  min-height: 62px;
  padding: 10px 16px 10px 22px;
  border-bottom: 1px solid var(--line);
}

.viewer-bar h2 { margin: 0; font-size: 18px; }

.viewer-actions {
  display: flex;
  gap: 8px;
}

.viewer-reset,
.viewer-close {
  min-height: 38px;
  padding: 0 14px;
  border: 1px solid var(--line);
  border-radius: 9px;
  background: #fff;
  font-family: inherit;
  font-weight: 850;
  cursor: pointer;
}

.viewer-reset:hover,
.viewer-close:hover {
  border-color: var(--ink);
}

.viewer-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 330px;
  height: calc(100% - 62px);
}

.viewer-workspace {
  display: grid;
  grid-template-rows: auto minmax(0, 1fr);
  min-width: 0;
  background: #eef2f6;
}

.viewer-hint {
  margin: 0;
  padding: 9px 16px;
  border-bottom: 1px solid var(--line);
  color: #475467;
  background: #fff;
  font-size: 12px;
  font-weight: 800;
}

.viewer-canvas {
  position: relative;
  overflow: auto;
  height: 100%;
  padding: 16px;
  background: #eef2f6;
}

.viewer-loading {
  display: grid;
  min-height: 240px;
  place-items: center;
  color: #667085;
  font-size: 14px;
  font-weight: 850;
}

.viewer-loading[hidden] { display: none; }

.viewer-diagram {
  min-width: 1400px;
  border: 1px solid var(--line);
  background: #fff;
}

.viewer-diagram:empty { display: none; }

.viewer-diagram .interactive-svg {
  display: block;
  width: 100%;
  height: auto;
}

.viewer-diagram svg text {
  pointer-events: none;
}

.viewer-diagram svg [data-component] {
  cursor: pointer;
  transition: opacity 140ms ease;
}

.viewer-diagram.has-selection .wire {
  opacity: 0.1;
}

.viewer-diagram.has-selection .net-tag {
  opacity: 0.16;
}

.viewer-diagram.has-selection svg [data-component] {
  opacity: 0.16;
}

.viewer-diagram.has-selection svg [data-component].is-selected,
.viewer-diagram.has-selection svg [data-component].is-connected-component,
.viewer-diagram.has-selection .wire.wire-highlight,
.viewer-diagram.has-selection .net-tag.net-tag-highlight {
  opacity: 1;
}

.viewer-diagram.has-selection .wire.wire-highlight {
  stroke-width: 7;
  filter: drop-shadow(0 0 4px rgba(15, 23, 42, 0.22));
}

.viewer-diagram svg [data-component].is-selected > rect,
.viewer-diagram svg [data-component].is-selected > circle {
  stroke: var(--blue);
  stroke-width: 4;
}

.viewer-diagram svg [data-component].is-connected-component > rect,
.viewer-diagram svg [data-component].is-connected-component > circle {
  stroke: var(--orange);
  stroke-width: 3;
}

.viewer-diagram .outside-label.is-selected rect {
  fill: #eff6ff;
  stroke: var(--blue);
  stroke-width: 3;
}

.viewer-diagram .outside-label.is-connected-component rect {
  fill: #fff7ed;
  stroke: var(--orange);
  stroke-width: 2.5;
}

.component-inspector {
  overflow: auto;
  padding: 20px;
  border-left: 1px solid var(--line);
  background: #fff;
}

.inspector-kicker {
  color: var(--blue);
  font-size: 10px;
  font-weight: 950;
  letter-spacing: 0.12em;
}

.component-inspector h3 {
  margin: 4px 0 0;
  font-size: 22px;
  line-height: 1.3;
}

.component-inspector > div > p {
  margin: 8px 0 0;
  color: var(--muted);
  font-size: 13px;
}

.component-picker {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
  margin-top: 18px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--line);
}

.component-choice {
  padding: 6px 9px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: #344054;
  background: #fff;
  font-family: inherit;
  font-size: 11px;
  font-weight: 850;
  cursor: pointer;
}

.component-choice:hover,
.component-choice.is-active {
  border-color: var(--blue);
  color: #fff;
  background: var(--blue);
}

.component-picker-empty,
.connection-empty {
  margin: 0;
  color: #667085;
  font-size: 12px;
}

.connection-list {
  display: grid;
  gap: 10px;
  margin-top: 18px;
}

.connection-item {
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #f8fafc;
}

.connection-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.connection-heading strong {
  position: relative;
  padding-left: 13px;
  font-size: 13px;
}

.connection-heading strong::before {
  position: absolute;
  top: 50%;
  left: 0;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--wire-color);
  content: "";
  transform: translateY(-50%);
}

.connection-targets {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 9px;
}

.connection-targets button {
  padding: 4px 7px;
  border: 1px solid var(--line);
  border-radius: 7px;
  color: var(--blue-dark);
  background: #fff;
  font-family: inherit;
  font-size: 10px;
  font-weight: 900;
  cursor: pointer;
}

.connection-targets button:hover {
  border-color: var(--orange);
  color: #9a3412;
}

.connection-targets span {
  color: #667085;
  font-size: 11px;
  font-weight: 800;
}

.connection-item p {
  margin: 7px 0 0;
  color: #475467;
  font-size: 11px;
  overflow-wrap: anywhere;
}

@media (max-width: 1040px) {
  .hero {
    grid-template-columns: 1fr;
    min-height: 0;
    padding-top: 58px;
  }

  .hero-copy { max-width: 820px; }
  .hero-preview { transform: none; }
  .rules, .connection-summary { grid-template-columns: 1fr; }

  .viewer-body {
    grid-template-columns: 1fr;
    grid-template-rows: minmax(55%, 1fr) minmax(240px, 35%);
  }

  .component-inspector {
    border-top: 1px solid var(--line);
    border-left: 0;
  }
}

@media (max-width: 760px) {
  .site-header {
    align-items: flex-start;
    min-height: 64px;
    padding: 12px 18px;
  }

  .brand > span:last-child { display: none; }
  nav { gap: 14px; font-size: 12px; }
  main { width: min(100% - 24px, 1560px); }

  .hero { gap: 30px; padding: 48px 0 54px; }
  .hero-copy h1 { font-size: clamp(34px, 10vw, 50px); }
  .hero-actions { display: grid; }
  .button { width: 100%; }
  .hero-preview { border-radius: 14px; }

  .rules { gap: 28px; padding: 28px 22px; }
  .rules ul { grid-template-columns: 1fr; }

  .layouts { padding: 78px 0 64px; }
  .section-heading { display: grid; }
  .filters { justify-content: flex-start; }
  .layout-list { grid-template-columns: 1fr; }
  .card-copy { min-height: 0; }

  .connection-summary {
    gap: 30px;
    margin-bottom: 64px;
    padding: 30px 24px;
  }

  footer { display: grid; }

  .viewer {
    width: 100vw;
    height: 100vh;
    max-width: none;
    max-height: none;
    border-radius: 0;
  }

  .viewer-bar {
    padding-left: 14px;
  }

  .viewer-reset,
  .viewer-close {
    padding: 0 10px;
    font-size: 12px;
  }

  .viewer-diagram {
    min-width: 1100px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; }
}