:root {
  --bg-page: #ffffff;
  --bg-soft: #f6f6f6;
  --bg-panel: #ffffff;
  --text-high: #151515;
  --text-med: #444746;
  --text-low: #70757a;
  --border: #e8e8e8;
  --accent: #b79353;
  --accent-dark: #8a6b3f;
  --black: #111111;
  --shadow: 0 18px 55px rgba(0, 0, 0, 0.08);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: "Google Sans", "Segoe UI", Arial, sans-serif;
}

body {
  min-height: 100vh;
  background: var(--bg-page);
  color: var(--text-high);
}

.topbar {
  height: 68px;
  padding: 0 28px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo-text {
  color: var(--black);
  font-size: 1.35rem;
  font-weight: 800;
  text-decoration: none;
}

.back-link {
  color: var(--text-med);
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  text-decoration: none;
}

.layout {
  width: min(1180px, calc(100vw - 32px));
  margin: 0 auto;
  padding: 44px 0;
}

.hero {
  max-width: 760px;
  margin-bottom: 34px;
}

.eyebrow {
  color: var(--accent-dark);
  font-size: 0.86rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  margin-bottom: 12px;
  text-transform: uppercase;
}

h1 {
  font-size: clamp(2.4rem, 5vw, 4.4rem);
  line-height: 0.98;
  letter-spacing: 0;
  max-width: 760px;
}

.lede {
  color: var(--text-med);
  font-size: 1.05rem;
  line-height: 1.65;
  margin-top: 20px;
  max-width: 680px;
}

.builder-shell {
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: 22px;
}

.model-panel,
.lanes-panel {
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-radius: 8px;
  box-shadow: var(--shadow);
  min-height: 560px;
  padding: 16px;
}

.panel-heading {
  align-items: center;
  color: var(--black);
  display: flex;
  font-weight: 800;
  gap: 8px;
  margin-bottom: 14px;
}

.model-library {
  display: grid;
  gap: 10px;
}

.model-card {
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 8px;
  cursor: grab;
  padding: 13px;
  transition:
    border-color 0.18s ease,
    box-shadow 0.18s ease,
    transform 0.18s ease;
}

.model-card:active {
  cursor: grabbing;
}

.model-card:hover {
  border-color: rgba(183, 147, 83, 0.55);
  box-shadow: 0 10px 28px rgba(0, 0, 0, 0.08);
  transform: translateY(-1px);
}

.model-name {
  font-weight: 800;
  margin-bottom: 5px;
}

.model-provider {
  color: var(--accent-dark);
  font-size: 0.82rem;
  font-weight: 800;
  margin-bottom: 5px;
}

.model-copy {
  color: var(--text-low);
  font-size: 0.86rem;
  line-height: 1.4;
}

.routing-lanes {
  display: grid;
  gap: 12px;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.lane {
  background: var(--bg-soft);
  border: 1px solid transparent;
  border-radius: 8px;
  min-height: 176px;
  padding: 14px;
  transition:
    background 0.18s ease,
    border-color 0.18s ease;
}

.lane.drag-over {
  background: #f0eadf;
  border-color: var(--accent);
}

.lane-title {
  align-items: center;
  color: var(--black);
  display: flex;
  font-weight: 800;
  gap: 8px;
  margin-bottom: 6px;
}

.lane-copy {
  color: var(--text-low);
  font-size: 0.88rem;
  line-height: 1.45;
  margin-bottom: 12px;
}

.drop-zone {
  display: grid;
  gap: 8px;
  min-height: 68px;
}

.assigned-card {
  align-items: center;
  background: #ffffff;
  border: 1px solid #dedede;
  border-radius: 8px;
  display: flex;
  gap: 10px;
  justify-content: space-between;
  padding: 10px 11px;
}

.assigned-card button {
  align-items: center;
  background: transparent;
  border: none;
  border-radius: 8px;
  color: var(--text-low);
  cursor: pointer;
  display: inline-flex;
  height: 30px;
  justify-content: center;
  width: 30px;
}

.assigned-card button:hover {
  background: #eeeeee;
  color: var(--black);
}

.empty-drop {
  align-items: center;
  border: 1px dashed #cfcfcf;
  border-radius: 8px;
  color: var(--text-low);
  display: flex;
  font-size: 0.9rem;
  min-height: 64px;
  padding: 0 12px;
}

.control-strip {
  align-items: center;
  display: flex;
  gap: 12px;
  margin-top: 18px;
}

.primary-action,
.secondary-action {
  align-items: center;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  display: inline-flex;
  font-weight: 800;
  gap: 8px;
  height: 44px;
  padding: 0 16px;
}

.primary-action {
  background: var(--black);
  color: #ffffff;
}

.secondary-action {
  background: #f3f3f3;
  color: var(--black);
}

.save-status {
  color: var(--accent-dark);
  font-size: 0.9rem;
  font-weight: 700;
}

@media (max-width: 880px) {
  .topbar {
    padding: 0 18px;
  }

  .builder-shell {
    grid-template-columns: 1fr;
  }

  .routing-lanes {
    grid-template-columns: 1fr;
  }
}