:root {
  --bgx-ink: #18333b;
  --bgx-muted: #587079;
  --bgx-accent: #236777;
  --bgx-accent-2: #7a6040;
  --bgx-line: #cbdadd;
  --bgx-wash: #edf4f4;
  --bgx-paper: #fffdf8;
  --bgx-note: #f4f1e8;
}

body[data-background-view] { color: var(--bgx-ink); }
.bgx-hero { background: radial-gradient(circle at 82% 12%, rgba(35, 103, 119, .13), transparent 24rem), linear-gradient(135deg, #f2f7f6, #f8f4eb); border-bottom: 1px solid var(--bgx-line); padding: clamp(2rem, 6vw, 5rem) 0 clamp(1.8rem, 4vw, 3.6rem); }
.bgx-hero__grid { align-items: end; display: grid; gap: 1.5rem 3rem; grid-template-columns: minmax(0, 1.35fr) minmax(280px, .65fr); }
.bgx-kicker, .bgx-section-kicker { color: var(--bgx-accent); font-size: .76rem; font-weight: 820; letter-spacing: .12em; margin: 0 0 .45rem; text-transform: uppercase; }
.bgx-hero h1 { font-size: clamp(2.25rem, 6vw, 5.4rem); letter-spacing: -.045em; line-height: .98; margin: 0; max-width: 13ch; }
.bgx-hero h1 span { color: var(--bgx-muted); display: block; font-size: .29em; font-weight: 680; letter-spacing: 0; line-height: 1.25; margin-top: .75rem; }
.bgx-lead { color: #3e5962; font-size: clamp(1rem, 2vw, 1.18rem); line-height: 1.75; margin: 1rem 0 0; max-width: 56rem; }
.bgx-hero__aside { background: rgba(255, 255, 255, .82); border: 1px solid rgba(35, 103, 119, .2); border-radius: 1rem; box-shadow: 0 12px 30px rgba(24, 51, 59, .08); padding: 1.15rem; }
.bgx-hero__aside strong { display: block; font-size: 1.06rem; margin-bottom: .35rem; }
.bgx-hero__aside p { color: var(--bgx-muted); line-height: 1.65; margin: 0; }
.bgx-main { padding: 2rem 0 4.5rem; }
.bgx-toolbar { background: #fff; border: 1px solid var(--bgx-line); border-radius: .9rem; display: grid; gap: .75rem; grid-template-columns: 1.5fr repeat(3, minmax(150px, .7fr)); padding: .85rem; position: sticky; top: .65rem; z-index: 4; }
.bgx-field { color: var(--bgx-muted); display: grid; font-size: .78rem; font-weight: 740; gap: .3rem; }
.bgx-field input, .bgx-field select { background: #fff; border: 1px solid #a9bec4; border-radius: .55rem; color: var(--bgx-ink); font: inherit; font-size: .92rem; min-height: 2.65rem; padding: .55rem .68rem; width: 100%; }
.bgx-filter-details { border-bottom: 1px solid var(--bgx-line); margin: .8rem 0 1.4rem; padding: 0 .2rem .8rem; }
.bgx-filter-details summary { color: var(--bgx-accent); cursor: pointer; font-weight: 740; padding: .55rem 0; }
.bgx-check-grid { display: grid; gap: .45rem .9rem; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); padding: .35rem 0; }
.bgx-check-grid label, .bgx-checklist label { align-items: start; display: flex; gap: .48rem; line-height: 1.45; }
.bgx-check-grid input, .bgx-checklist input { accent-color: var(--bgx-accent); margin-top: .23rem; }
.bgx-section { margin-top: 2.6rem; }
.bgx-section__head { align-items: end; display: flex; flex-wrap: wrap; gap: .7rem 2rem; justify-content: space-between; margin-bottom: 1rem; }
.bgx-section__head h2 { font-size: clamp(1.55rem, 3vw, 2.35rem); letter-spacing: -.025em; margin: 0; }
.bgx-section__head p { color: var(--bgx-muted); margin: 0; max-width: 42rem; }
.bgx-grid, .bgx-template-grid { display: grid; gap: .85rem; grid-template-columns: repeat(3, minmax(0, 1fr)); }
.bgx-template-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.bgx-card { background: var(--bgx-paper); border: 1px solid var(--bgx-line); border-radius: .9rem; box-shadow: 0 7px 20px rgba(24, 51, 59, .055); display: flex; flex-direction: column; min-width: 0; padding: 1rem; }
.bgx-card--template { background: linear-gradient(145deg, #fff, #eff6f5); border-top: 4px solid var(--bgx-accent); padding: 1.2rem; }
.bgx-card__top { align-items: start; display: flex; gap: .6rem; justify-content: space-between; }
.bgx-card h3 { font-size: 1.1rem; line-height: 1.3; margin: 0; }
.bgx-card h3 span { color: var(--bgx-muted); display: block; font-size: .73em; font-weight: 620; margin-top: .25rem; }
.bgx-card__abbr { border: 1px solid #9eb8bf; border-radius: 99px; color: var(--bgx-accent); flex: none; font-size: .72rem; font-weight: 800; padding: .25rem .45rem; }
.bgx-card__sentence { color: #405c64; flex: 1; line-height: 1.62; margin: .75rem 0; }
.bgx-card__meta { color: var(--bgx-muted); font-size: .8rem; margin: 0 0 .7rem; }
.bgx-tags, .bgx-badge-row { display: flex; flex-wrap: wrap; gap: .35rem; }
.bgx-tag, .bgx-badge { background: #eef2ef; border: 1px solid #d4ddd8; border-radius: 99px; color: #4c625f; display: inline-flex; font-size: .71rem; font-weight: 700; line-height: 1.2; padding: .28rem .48rem; }
.bgx-badge--review { background: #f5efe3; border-color: #dfcfaa; color: #745b32; }
.bgx-card__actions, .bgx-actions { align-items: center; display: flex; flex-wrap: wrap; gap: .5rem; margin-top: .9rem; }
.bgx-button { align-items: center; background: var(--bgx-accent); border: 1px solid var(--bgx-accent); border-radius: .55rem; color: #fff; cursor: pointer; display: inline-flex; font: inherit; font-size: .84rem; font-weight: 760; justify-content: center; min-height: 2.45rem; padding: .48rem .72rem; text-decoration: none; }
.bgx-button--quiet { background: transparent; color: var(--bgx-accent); }
.bgx-button:focus-visible, .bgx-card a:focus-visible, .bgx-compare-panel:focus-visible { outline: 3px solid #d6a451; outline-offset: 3px; }
.bgx-count { color: var(--bgx-muted); font-size: .88rem; }
.bgx-empty { background: var(--bgx-note); border: 1px dashed #c7b98f; border-radius: .75rem; color: #665d48; grid-column: 1 / -1; padding: 1.2rem; }
.bgx-boundary { background: var(--bgx-note); border-left: 4px solid var(--bgx-accent-2); border-radius: .2rem .75rem .75rem .2rem; line-height: 1.65; padding: 1rem 1.1rem; }
.bgx-link-cluster { display: grid; gap: .75rem; grid-template-columns: repeat(3, minmax(0, 1fr)); }
.bgx-link-cluster a { background: #fff; border: 1px solid var(--bgx-line); border-radius: .75rem; color: var(--bgx-ink); padding: 1rem; text-decoration: none; }
.bgx-link-cluster a strong, .bgx-link-cluster a span { display: block; }
.bgx-link-cluster a span { color: var(--bgx-muted); font-size: .84rem; margin-top: .3rem; }
.bgx-detail-nav { align-items: center; display: flex; flex-wrap: wrap; gap: .6rem; justify-content: space-between; margin-bottom: 1rem; }
.bgx-detail-title { border-bottom: 1px solid var(--bgx-line); padding-bottom: 1.4rem; }
.bgx-detail-title h1 { font-size: clamp(2rem, 5vw, 4rem); letter-spacing: -.04em; margin: .2rem 0 .5rem; }
.bgx-detail-title h1 span { color: var(--bgx-muted); display: block; font-size: .37em; font-weight: 620; letter-spacing: 0; margin-top: .45rem; }
.bgx-center-sentence { color: #354f57; font-size: 1.12rem; line-height: 1.75; margin: .8rem 0 0; max-width: 66rem; }
.bgx-detail-grid { display: grid; gap: 1rem; grid-template-columns: repeat(2, minmax(0, 1fr)); margin-top: 1.4rem; }
.bgx-panel { background: #fff; border: 1px solid var(--bgx-line); border-radius: .8rem; min-width: 0; padding: 1rem; }
.bgx-panel--wide { grid-column: 1 / -1; }
.bgx-panel h2, .bgx-panel h3 { margin-top: 0; }
.bgx-panel p, .bgx-panel li, .bgx-source-card p { color: #415b63; line-height: 1.65; }
.bgx-panel ul, .bgx-panel ol { padding-left: 1.25rem; }
.bgx-progression { counter-reset: step; display: grid; gap: .55rem; grid-template-columns: repeat(5, minmax(0, 1fr)); list-style: none; padding: 0 !important; }
.bgx-progression li { background: linear-gradient(145deg, #f6f5ef, #edf3f3); border: 1px solid var(--bgx-line); border-radius: .65rem; counter-increment: step; font-size: .84rem; min-height: 6.5rem; padding: .75rem; }
.bgx-progression li::before { color: var(--bgx-accent); content: counter(step, decimal-leading-zero); display: block; font-size: .72rem; font-weight: 820; margin-bottom: .55rem; }
.bgx-compare-shell { background: #172a30; border-radius: .9rem; color: #eef6f6; overflow: hidden; }
.bgx-compare-toolbar { align-items: center; display: flex; flex-wrap: wrap; gap: .55rem; justify-content: space-between; padding: .75rem; }
.bgx-compare-toolbar__group { align-items: center; display: flex; flex-wrap: wrap; gap: .4rem; }
.bgx-compare-toolbar button, .bgx-compare-toolbar label { background: #25424a; border: 1px solid #526b72; border-radius: .45rem; color: #eef6f6; cursor: pointer; font: inherit; font-size: .78rem; padding: .42rem .55rem; }
.bgx-compare-grid { display: grid; gap: 1px; grid-template-columns: repeat(4, minmax(0, 1fr)); }
.bgx-compare-panel { background: #20383f; min-width: 0; outline: none; }
.bgx-compare-panel h3 { font-size: .87rem; margin: 0; padding: .65rem .7rem; }
.bgx-compare-stage { aspect-ratio: 4 / 3; background: #0f2025; cursor: grab; overflow: hidden; position: relative; }
.bgx-compare-stage:active { cursor: grabbing; }
.bgx-compare-stage img { height: 100%; object-fit: contain; transform: translate(var(--pan-x, 0px), var(--pan-y, 0px)) scale(var(--zoom, 1)); transform-origin: center; transition: transform .12s ease-out; width: 100%; }
.bgx-marker { border: 2px solid #f2cf7b; border-radius: 50%; box-shadow: 0 0 0 999px rgba(14, 30, 35, .22); display: none; height: 26%; left: 40%; pointer-events: none; position: absolute; top: 34%; width: 24%; }
.bgx-compare-shell[data-markers="on"] .bgx-marker { display: block; }
.bgx-source-card { align-content: center; background: linear-gradient(145deg, #263f46, #162c32); display: grid; height: 100%; padding: .85rem; }
.bgx-source-card strong, .bgx-source-card span { display: block; }
.bgx-source-card p, .bgx-source-card span { color: #bed0d3; font-size: .78rem; }
.bgx-source-card a { color: #f0d7a5; }
.bgx-compare-meta { color: #c5d4d7; font-size: .73rem; line-height: 1.45; overflow-wrap: anywhere; padding: .65rem .7rem .8rem; }
.bgx-panel dd, .bgx-evidence-fields p { overflow-wrap: anywhere; word-break: break-word; }
.bgx-comparison-note { background: #f1eadc; border: 1px solid #d8c49b; border-radius: .65rem; color: #6c5630; line-height: 1.55; margin-top: .75rem; padding: .75rem; }
.bgx-checklist { columns: 2; column-gap: 2rem; }
.bgx-checklist label { break-inside: avoid; margin-bottom: .55rem; }
.bgx-report-list { display: grid; gap: .65rem; }
.bgx-report-list article { background: #f8faf9; border: 1px solid var(--bgx-line); border-radius: .65rem; padding: .8rem; }
.bgx-report-list h3 { font-size: .88rem; margin-bottom: .35rem; }
.bgx-report-list p { margin: 0; }
.bgx-source-list { display: grid; gap: .6rem; }
.bgx-source-list a { overflow-wrap: anywhere; }
.bgx-challenge-grid { display: grid; gap: 1rem; grid-template-columns: repeat(3, minmax(0, 1fr)); }
.bgx-challenge { background: #fff; border: 1px solid var(--bgx-line); border-radius: .85rem; padding: 1rem; }
.bgx-challenge fieldset { border: 0; margin: .8rem 0; padding: 0; }
.bgx-challenge label { align-items: start; background: #f6f8f7; border: 1px solid #d7e0de; border-radius: .55rem; display: flex; gap: .45rem; margin: .4rem 0; padding: .55rem; }
.bgx-answer { background: var(--bgx-note); border-left: 3px solid var(--bgx-accent-2); margin-top: .75rem; padding: .8rem; }
.bgx-answer[hidden] { display: none; }
.bgx-queue { width: 100%; }
.bgx-queue th, .bgx-queue td { border-bottom: 1px solid var(--bgx-line); padding: .65rem; text-align: left; vertical-align: top; }
.bgx-queue th { color: var(--bgx-muted); font-size: .76rem; }

@media (max-width: 980px) {
  .bgx-hero__grid, .bgx-toolbar { grid-template-columns: 1fr 1fr; }
  .bgx-hero__grid > :first-child, .bgx-toolbar > :first-child { grid-column: 1 / -1; }
  .bgx-grid, .bgx-challenge-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .bgx-compare-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 640px) {
  .bgx-hero { padding-top: 1.4rem; }
  .bgx-hero__grid, .bgx-toolbar, .bgx-grid, .bgx-template-grid, .bgx-detail-grid, .bgx-link-cluster, .bgx-challenge-grid, .bgx-compare-grid { grid-template-columns: 1fr; }
  .bgx-toolbar { position: static; }
  .bgx-progression { grid-template-columns: 1fr; }
  .bgx-progression li { min-height: 0; }
  .bgx-checklist { columns: 1; }
  .bgx-queue { display: block; overflow-x: auto; }
}

@media (prefers-reduced-motion: reduce) {
  .bgx-compare-stage img { transition: none; }
}