:root {
  --signal: #ff5a3d;
  --signal-dark: #b92f1d;
  --deep: #062f36;
  --deep-2: #0d4650;
  --mint: #d9f4ee;
  --paper: #fffdf8;
  --soft: #f1eee6;
  --ink: #102f35;
  --muted: #52676b;
  --line: #b9cbc8;
  --white: #ffffff;
  --measure: 78rem;
}

* { box-sizing: border-box; }

html {
  background: var(--paper);
  color: var(--ink);
  font-family: "IBM Plex Sans", "Aptos", "Segoe UI", system-ui, sans-serif;
  line-height: 1.62;
  scroll-behavior: smooth;
}

body { margin: 0; }

a {
  color: #075f78;
  font-weight: 650;
  text-decoration-thickness: .1em;
  text-underline-offset: .2em;
}

a:hover { color: var(--signal-dark); }

a:focus-visible,
summary:focus-visible {
  outline: 3px solid var(--signal);
  outline-offset: 4px;
}

.jump-link {
  position: fixed;
  z-index: 40;
  top: .8rem;
  left: .8rem;
  padding: .75rem 1rem;
  background: var(--white);
  color: #000;
  transform: translateY(-180%);
}

.jump-link:focus { transform: none; }

.mast {
  position: relative;
  overflow: hidden;
  color: var(--white);
  background: var(--deep);
}

.mast::after {
  content: "";
  position: absolute;
  width: 28rem;
  height: 28rem;
  right: -8rem;
  bottom: -16rem;
  border: 3.5rem solid rgba(217, 244, 238, .12);
  border-radius: 50%;
}

.mast__bar,
.page-grid,
.foot__inside {
  width: min(calc(100% - 2rem), var(--measure));
  margin-inline: auto;
}

.mast__bar {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  min-height: 5.25rem;
  border-bottom: 1px solid rgba(255, 255, 255, .24);
}

.mark {
  display: inline-flex;
  align-items: center;
  gap: .75rem;
  color: var(--white);
  text-decoration: none;
}

.mark img { width: 2.9rem; height: 2.9rem; }
.mark span { display: grid; line-height: 1.15; }
.mark small { color: #a9dad2; font-size: .7rem; letter-spacing: .1em; text-transform: uppercase; }

.mast nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: .4rem 1.25rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.mast nav a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  color: var(--white);
  font-size: .92rem;
}

.hero {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1.55fr) minmax(17rem, .7fr);
  gap: clamp(2rem, 6vw, 6rem);
  padding: clamp(3rem, 8vw, 7rem) 0;
}

.eyebrow {
  margin: 0 0 .75rem;
  color: #93e6d9;
  font-size: .76rem;
  font-weight: 800;
  letter-spacing: .16em;
  text-transform: uppercase;
}

.hero h1 {
  max-width: 15ch;
  margin: 0;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(2.75rem, 7vw, 6.6rem);
  font-weight: 500;
  letter-spacing: -.045em;
  line-height: .95;
  text-wrap: balance;
}

.hero__intro {
  max-width: 62ch;
  margin: 1.4rem 0 0;
  color: #d2e9e5;
  font-size: clamp(1.05rem, 1.8vw, 1.25rem);
}

.signal-card {
  align-self: end;
  padding: 1.4rem;
  color: var(--deep);
  background: var(--mint);
  border-top: .45rem solid var(--signal);
}

.signal-card b { display: block; margin-bottom: .5rem; font-size: 1.12rem; }
.signal-card p { margin: 0; }

.page-grid {
  display: grid;
  grid-template-columns: 14rem minmax(0, 1fr);
  gap: clamp(2rem, 6vw, 5rem);
  padding-block: clamp(2.5rem, 6vw, 5.5rem);
}

.rail { align-self: start; position: sticky; top: 1rem; }
.rail p { margin: 0 0 .35rem; color: var(--muted); font-size: .86rem; }
.rail strong { color: var(--ink); }
.rail__rule { height: 5px; margin: 1.1rem 0; background: linear-gradient(90deg, var(--signal) 42%, var(--mint) 42%); }
.rail ol { margin: 0; padding-left: 1.3rem; color: var(--muted); font-size: .86rem; }

.article-flow { min-width: 0; }
.article-flow section { scroll-margin-top: 1rem; }

.direct {
  display: grid;
  grid-template-columns: 9rem 1fr;
  gap: 1.4rem;
  padding: 1.5rem;
  background: var(--mint);
  border: 1px solid #9bcfc5;
  box-shadow: .65rem .65rem 0 var(--deep);
}

.direct h2 {
  margin: 0;
  color: var(--deep-2);
  font-size: .78rem;
  letter-spacing: .12em;
  text-transform: uppercase;
}

.direct p { margin: 0; font-size: 1.08rem; }

.boundary {
  margin: 2.5rem 0;
  padding: 1.25rem 1.35rem;
  background: #fff1ec;
  border-left: .42rem solid var(--signal);
}

.boundary h2 { margin: 0 0 .35rem; font-size: 1.05rem; }
.boundary p { margin: 0; }

.section-head {
  max-width: 26ch;
  margin: 4rem 0 1.2rem;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(1.9rem, 4vw, 3.2rem);
  font-weight: 500;
  letter-spacing: -.025em;
  line-height: 1.05;
}

.table-window {
  max-width: 100%;
  overflow-x: auto;
  background: var(--white);
  border: 1px solid var(--line);
}

.table-window:focus-visible { outline: 3px solid var(--signal); outline-offset: 3px; }

table { width: 100%; min-width: 72rem; border-collapse: collapse; font-size: .9rem; }
caption { padding: 1rem; color: var(--muted); text-align: left; }
th, td { padding: .9rem .85rem; text-align: left; vertical-align: top; border-bottom: 1px solid var(--line); }
thead th { color: var(--white); background: var(--deep); }
tbody tr:nth-child(even) { background: #f6f4ee; }
tbody tr:first-child td:first-child { border-left: .42rem solid var(--signal); }
.rank-dot { display: inline-grid; place-items: center; width: 2rem; height: 2rem; color: var(--white); background: var(--deep-2); border-radius: 50%; font-weight: 800; }

.lane-board {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.lane-board article { padding: 1.25rem; background: var(--white); }
.lane-board article:first-child { border-top: .4rem solid var(--signal); }
.lane-board article:nth-child(2) { border-top: .4rem solid #16968a; }
.lane-board article:nth-child(3) { border-top: .4rem solid #cf9b22; }
.lane-board h3 { margin: 0 0 .55rem; }
.lane-board p { margin: 0; }

.weight-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: .75rem;
  margin: 1rem 0 0;
  padding: 0;
  list-style: none;
}

.weight-list li { padding: 1rem; background: var(--soft); border-left: 3px solid var(--deep-2); }
.weight-list b { display: block; color: var(--signal-dark); font-size: 1.2rem; }

.question-bank { display: grid; gap: .75rem; }
.question-bank details { background: var(--white); border: 1px solid var(--line); }
.question-bank summary { position: relative; min-height: 48px; padding: .95rem 3rem .95rem 1rem; cursor: pointer; list-style: none; font-weight: 760; }
.question-bank summary::-webkit-details-marker { display: none; }
.question-bank summary::after { content: "+"; position: absolute; right: 1rem; color: var(--signal-dark); font-size: 1.4rem; }
.question-bank details[open] summary::after { content: "x"; }
.question-bank details p { margin: 0; padding: 0 1rem 1rem; }

.source-grid { columns: 2; column-gap: 2rem; padding-left: 1.2rem; }
.source-grid li { break-inside: avoid; margin: 0 0 .85rem; }

.foot { color: #d9ece9; background: var(--deep); }
.foot__inside { display: grid; grid-template-columns: 1.2fr 1fr; gap: 2rem; padding-block: 2.4rem; }
.foot p { margin: .35rem 0; }
.foot a { color: #a9eee4; }

@media (max-width: 880px) {
  .hero, .page-grid { grid-template-columns: 1fr; }
  .rail { position: static; display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
  .rail__rule { grid-column: 1 / -1; margin: 0; }
  .lane-board { grid-template-columns: 1fr; }
}

@media (max-width: 620px) {
  .mast__bar { align-items: flex-start; flex-direction: column; padding-block: 1rem; }
  .mast nav ul { display: grid; grid-template-columns: 1fr 1fr; width: 100%; }
  .hero h1 { font-size: 3rem; }
  .direct { grid-template-columns: 1fr; }
  .weight-list, .foot__inside, .rail { grid-template-columns: 1fr; }
  .source-grid { columns: 1; }
}

@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }