:root {
  color-scheme: light;
  --ink: #18202a;
  --muted: #617082;
  --paper: #f4f6f8;
  --surface: #ffffff;
  --surface-subtle: #f8fafb;
  --line: #d8e0e8;
  --primary: #126754;
  --primary-dark: #0a4639;
  --primary-soft: #eef7f3;
  --info: #2f5f87;
  --info-soft: #eef3f7;
  --success: #047857;
  --success-soft: #effaf5;
  --warning: #8a5a00;
  --warning-soft: #fff7df;
  --danger: #8f2020;
  --danger-soft: #fff0f0;
  --shadow: 0 8px 22px rgba(24, 32, 42, 0.07);
  font-family: Arial, Helvetica, sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  overflow-x: hidden;
  color: var(--ink);
  background: linear-gradient(180deg, #fbfcfd 0, var(--paper) 34rem);
}

button, input, select { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
:where(button, a, input, select):focus-visible { outline: 3px solid var(--primary-dark); outline-offset: 2px; }

.topbar {
  min-height: 72px;
  display: flex;
  align-items: center;
  gap: 2rem;
  padding: 0.8rem clamp(1rem, 4vw, 4rem);
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(10px);
  position: sticky;
  top: 0;
  z-index: 10;
}

.brand { display: flex; align-items: center; gap: 0.75rem; color: inherit; text-decoration: none; margin-right: auto; }
.brand-mark { display: block; width: 42px; height: 42px; border-radius: 13px; }
.brand strong, .brand small { display: block; }
.brand strong { font-size: 1rem; letter-spacing: -0.02em; }
.brand small { margin-top: 0.1rem; color: var(--muted); font-size: 0.75rem; }

nav { display: flex; gap: 0.3rem; }
.nav-button { display: inline-flex; align-items: center; gap: 0.38rem; border: 0; border-radius: 999px; padding: 0.48rem 0.62rem 0.48rem 0.8rem; color: var(--muted); background: transparent; cursor: pointer; }
.nav-button:hover { color: var(--ink); background: #eef2f5; }
.nav-button.is-active { color: white; background: var(--primary); }
.nav-count { display: inline-flex; min-width: 1.45rem; min-height: 1.35rem; align-items: center; justify-content: center; padding: 0.1rem 0.38rem; border-radius: 999px; color: #526171; background: #e8edf1; font-size: 0.68rem; font-weight: 800; line-height: 1; }
.nav-button.is-active .nav-count { color: white; background: rgba(255, 255, 255, 0.18); }
.utility-links { display: flex; align-items: center; gap: 0.75rem; }
.docs-link, .github-link { padding: 0.48rem 0.72rem; border: 1px solid var(--line); border-radius: 999px; color: var(--primary-dark); background: var(--surface); font-size: 0.84rem; font-weight: 700; text-decoration: none; white-space: nowrap; }
.docs-link:hover, .github-link:hover { border-color: #9eb6ae; background: var(--primary-soft); }
.docs-label-short { display: none; }
.source-link { color: var(--primary-dark); font-size: 0.86rem; font-weight: 700; text-decoration: none; }

main { width: min(1280px, calc(100% - 2rem)); margin: 0 auto; }
.hero { display: grid; grid-template-columns: minmax(0, 1.45fr) minmax(300px, 0.55fr); gap: 2.5rem; align-items: end; padding: clamp(2.5rem, 5vw, 4.5rem) 0 1.75rem; }
.hero > *, .search-panel, .period-card { min-width: 0; }
.eyebrow { margin: 0 0 0.75rem; color: var(--primary); font-size: 0.73rem; font-weight: 800; letter-spacing: 0.12em; text-transform: uppercase; }
.hero h1 { max-width: 720px; margin: 0; font-family: Arial, Helvetica, sans-serif; font-size: clamp(2rem, 2.7vw, 2.65rem); font-weight: 700; line-height: 1.08; letter-spacing: -0.035em; }
.hero-copy > p:last-child { max-width: 720px; margin: 1.15rem 0 0; color: var(--muted); font-size: clamp(1rem, 1.5vw, 1.1rem); line-height: 1.6; }
.period-card { padding: 0.9rem 1rem; border: 1px solid var(--line); border-left: 3px solid #d58a3a; border-radius: 10px; background: var(--surface); box-shadow: 0 4px 14px rgba(24, 32, 42, 0.05); }
.period-card > span, .period-card small { display: block; color: var(--muted); font-size: 0.78rem; }
.period-tabs { display: flex; gap: 0.65rem; margin: 0.55rem -0.35rem 0.45rem; padding: 0.15rem 0.35rem 0.35rem; overflow-x: auto; overscroll-behavior-inline: contain; scrollbar-width: thin; }
.period-year-group, .period-pill-row { display: flex; align-items: center; gap: 0.4rem; flex: 0 0 auto; }
.period-year-group + .period-year-group { padding-left: 0.65rem; border-left: 1px solid var(--line); }
.period-year { color: var(--muted); font-size: 0.67rem; font-weight: 800; letter-spacing: 0.06em; }
.period-pill { display: inline-flex; align-items: center; gap: 0.35rem; padding: 0.48rem 0.7rem; border: 1px solid #cbd5dd; border-radius: 999px; color: var(--ink); background: var(--surface); font-size: 0.73rem; font-weight: 750; white-space: nowrap; cursor: pointer; }
.period-pill:hover { border-color: #8ba49d; background: #f8faf9; }
.period-pill.is-active { border-color: var(--primary); color: white; background: var(--primary); box-shadow: 0 4px 12px rgba(18,103,84,.18); }
.period-pill:disabled { cursor: wait; opacity: 0.72; }
.period-pill.is-active:disabled { opacity: 1; }
.period-loading { padding: 0.45rem 0; }
.period-spinner { width: 0.65rem; height: 0.65rem; border: 1.5px solid currentColor; border-right-color: transparent; border-radius: 50%; animation: period-spin 700ms linear infinite; }
@keyframes period-spin { to { transform: rotate(360deg); } }

.search-panel { padding: clamp(1.2rem, 3vw, 1.6rem); border: 1px solid var(--line); border-radius: 12px; background: var(--surface); box-shadow: var(--shadow); }
.search-panel > label { display: block; margin-bottom: 0.6rem; font-size: 0.82rem; font-weight: 750; }
.search-row { display: grid; grid-template-columns: auto minmax(0, 1fr) auto; align-items: center; gap: 0.6rem; padding: 0.3rem 0.35rem 0.3rem 0.9rem; border: 1px solid #aebbc6; border-radius: 8px; }
.search-row:focus-within { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(18, 103, 84, 0.11); }
.search-icon { color: var(--primary); font-size: 1.6rem; transform: rotate(-20deg); }
.search-row input { min-width: 0; padding: 0.75rem 0.2rem; border: 0; outline: 0; color: var(--ink); background: transparent; font-size: 1.05rem; }
.search-row button { padding: 0.65rem 0.9rem; border: 1px solid var(--line); border-radius: 6px; color: var(--ink); background: #eef2f5; cursor: pointer; }
.search-row button:hover { border-color: #b7c2cb; background: #e6ebef; }
.filter-row { display: flex; flex-wrap: wrap; gap: 1rem; margin-top: 1rem; }
.filter-row label { display: grid; gap: 0.35rem; min-width: 230px; }
.filter-row span { color: var(--muted); font-size: 0.75rem; font-weight: 700; }
.filter-row select { padding: 0.62rem 2rem 0.62rem 0.7rem; border: 1px solid var(--line); border-radius: 6px; color: var(--ink); background: var(--surface-subtle); }

.content-grid { display: grid; grid-template-columns: minmax(0, 1.45fr) minmax(330px, 0.75fr); gap: 2rem; align-items: start; margin-top: 1.6rem; }
.section-heading { display: flex; justify-content: space-between; align-items: end; gap: 1rem; margin-bottom: 1rem; }
.section-heading h2 { margin: 0; font-family: Arial, Helvetica, sans-serif; font-size: clamp(1.6rem, 3vw, 2.25rem); font-weight: 700; }
#resultCount { margin: 0; color: var(--muted); font-size: 0.82rem; }
.results { display: grid; gap: 0.75rem; }
.result-card { width: 100%; display: grid; grid-template-columns: auto minmax(0, 1fr) auto; gap: 1rem; align-items: center; padding: 1rem; border: 1px solid var(--line); border-radius: 9px; text-align: left; color: inherit; background: var(--surface); cursor: pointer; transition: 160ms ease; }
.result-card:hover, .result-card.is-selected { border-color: #7f9f95; background: white; box-shadow: 0 6px 18px rgba(24, 32, 42, 0.07); }
.result-card.is-selected { box-shadow: inset 3px 0 0 var(--primary), 0 6px 18px rgba(24, 32, 42, 0.07); }
.cn-badge { min-width: 74px; padding: 0.45rem 0.55rem; border-radius: 6px; color: #344250; background: #edf1f4; font: 800 0.76rem/1 ui-monospace, SFMono-Regular, Menlo, monospace; text-align: center; }
.result-main { min-width: 0; }
.result-main h3 { margin: 0 0 0.3rem; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: 0.96rem; }
.result-main p { margin: 0; overflow: hidden; color: var(--muted); font-size: 0.78rem; text-overflow: ellipsis; white-space: nowrap; }
.change-chips { display: flex; justify-content: flex-end; flex-wrap: wrap; gap: 0.3rem; }
.chip { padding: 0.32rem 0.5rem; border-radius: 999px; color: var(--info); background: var(--info-soft); font-size: 0.75rem; font-weight: 750; white-space: nowrap; }
.chip--added { color: var(--success); background: var(--success-soft); }
.chip--removed { color: var(--danger); background: var(--danger-soft); }
.chip--price { color: var(--warning); background: var(--warning-soft); }
.chip--unchanged { color: #4d5b68; background: #eef2f5; }
.empty, .error { padding: 2rem; border: 1px dashed #b7c2ce; border-radius: 10px; color: var(--muted); text-align: center; }
.error { color: var(--danger); border-color: #d9afb1; background: var(--danger-soft); }

.detail-panel { position: sticky; top: 88px; min-height: 380px; max-height: calc(100vh - 108px); overflow: auto; border: 1px solid var(--line); border-radius: 12px; background: var(--surface); box-shadow: var(--shadow); }
.detail-placeholder { min-height: 380px; display: grid; place-content: center; padding: 2.5rem; text-align: center; }
.detail-placeholder > span { color: #d7a66c; font: 500 4.5rem/1 Arial, Helvetica, sans-serif; }
.detail-placeholder h2 { margin: 0.6rem 0; font-family: Arial, Helvetica, sans-serif; font-weight: 700; }
.detail-placeholder p { max-width: 330px; margin: 0; color: var(--muted); line-height: 1.55; }
.detail-content { padding: clamp(1.25rem, 3vw, 2rem); }
.detail-kicker { display: flex; justify-content: space-between; gap: 1rem; color: var(--muted); font-size: 0.75rem; }
.detail-content h2 { margin: 0.6rem 0; font-family: Arial, Helvetica, sans-serif; font-size: 1.65rem; line-height: 1.12; font-weight: 700; }
.detail-lab { margin: 0 0 1.3rem; color: var(--muted); font-size: 0.82rem; }
.current-state { display: grid; grid-template-columns: 1fr 1fr; gap: 0.65rem; padding: 1rem; border: 1px solid #e3e8ed; border-radius: 8px; background: var(--surface-subtle); }
.current-state div { min-width: 0; }
.current-state dt { margin-bottom: 0.15rem; color: var(--muted); font-size: 0.67rem; text-transform: uppercase; }
.current-state dd { margin: 0; overflow-wrap: anywhere; font-size: 0.8rem; }
.timeline-title { margin: 1.5rem 0 0.8rem; font-size: 0.78rem; text-transform: uppercase; letter-spacing: 0.07em; }
.timeline { display: grid; gap: 0.8rem; }
.unchanged-notice { margin: 1rem 0; padding: 0.9rem 1rem; border: 1px solid var(--line); border-radius: 8px; background: var(--surface-subtle); }
.unchanged-notice strong { color: var(--ink); font-size: 0.8rem; }
.unchanged-notice p { margin: 0.3rem 0 0; color: var(--muted); font-size: 0.76rem; line-height: 1.5; }
.event { padding-left: 1rem; border-left: 2px solid var(--line); }
.event header { display: flex; justify-content: space-between; gap: 0.7rem; align-items: baseline; }
.event strong { font-size: 0.82rem; }
.event time { color: var(--muted); font-size: 0.68rem; }
.event-field { margin: 0.2rem 0 0.45rem; color: var(--muted); font-size: 0.7rem; }
.value-change { display: grid; grid-template-columns: minmax(0,1fr) auto minmax(0,1fr); gap: 0.45rem; align-items: center; }
.value { padding: 0.5rem; border-radius: 6px; background: #f0f3f5; font-size: 0.72rem; overflow-wrap: anywhere; }
.value--after { color: var(--info); background: var(--info-soft); }
.arrow { color: var(--muted); font-size: 0.7rem; }
.provenance { margin-top: 1.5rem; padding-top: 1rem; border-top: 1px solid var(--line); color: var(--muted); font-size: 0.78rem; line-height: 1.5; }
.provenance strong { color: var(--ink); font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.06em; }
.provenance p { margin: 0.45rem 0 0; }
.provenance a { color: var(--primary); }

.method-note { display: grid; grid-template-columns: 0.8fr 1.2fr; gap: 3rem; margin: 5rem 0 2rem; padding: 2rem; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.method-note h2 { margin: 0; font: 700 1.7rem/1.1 Arial, Helvetica, sans-serif; }
.method-note > p { margin: 0; color: var(--muted); line-height: 1.7; }
footer { display: flex; justify-content: space-between; gap: 2rem; padding: 2rem clamp(1rem, 4vw, 4rem) 3rem; color: var(--muted); font-size: 0.72rem; }
footer p { max-width: 620px; margin: 0; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .period-spinner { animation: none; }
}

@media (max-width: 920px) {
  .topbar { flex-wrap: wrap; gap: 0.6rem 1rem; }
  .topbar nav { order: 3; width: 100%; }
  .source-link { display: none; }
  .hero { grid-template-columns: 1fr; gap: 1.5rem; }
  .content-grid { grid-template-columns: 1fr; }
  .detail-panel { position: static; max-height: none; }
  .method-note { grid-template-columns: 1fr; gap: 1rem; }
}

@media (max-width: 580px) {
  .topbar { column-gap: 0.5rem; }
  main { width: min(100% - 1rem, 1280px); }
  .brand small { display: none; }
  .utility-links { gap: 0.4rem; }
  .docs-link, .github-link { padding: 0.4rem 0.55rem; font-size: 0.78rem; }
  .docs-label-full { display: none; }
  .docs-label-short { display: inline; }
  .nav-button { padding-inline: 0.75rem; }
  .hero { padding-top: 3rem; }
  .hero h1 { font-size: clamp(1.9rem, 9vw, 2.45rem); }
  .search-panel { padding: 1rem; }
  .search-row { gap: 0.3rem; padding-left: 0.65rem; }
  .search-row button { padding-inline: 0.65rem; }
  .filter-row label { min-width: 0; width: 100%; }
  .result-card { grid-template-columns: 1fr; gap: 0.55rem; }
  .cn-badge { width: fit-content; }
  .change-chips { justify-content: flex-start; }
  .current-state { grid-template-columns: 1fr; }
  footer { flex-direction: column; }
}