.frontier {
  padding: 120px clamp(20px, 7vw, 110px);
  background: #eef0e9;
  border-bottom: 1px solid var(--line);
}

.frontier-head {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(260px, .6fr);
  column-gap: 6vw;
  align-items: end;
  margin-bottom: 46px;
}

.frontier-head .eyebrow { grid-column: 1 / -1; }
.frontier-head h2 { margin: .22em 0 0; font-size: clamp(3.8rem, 7vw, 7.5rem); }
.frontier-head > p:last-child { margin: 0 0 1.1rem; color: #5f6865; font-size: 1.03rem; }

.frontier-card {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(34px, 6vw, 90px);
  align-items: center;
  min-height: 640px;
  margin-top: 22px;
  padding: clamp(32px, 5vw, 72px);
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 30px;
  background: var(--paper);
}

.track-copy { max-width: 660px; }
.track-copy h3, .music-copy h3 { margin: .25em 0; font: 500 clamp(3rem, 5vw, 5.6rem)/.94 var(--serif); letter-spacing: -.052em; }
.track-copy > p:not(.eyebrow):not(.evidence-note), .music-copy > p:not(.eyebrow) { font-size: 1.03rem; }
.track-tags { display: flex; flex-wrap: wrap; gap: 7px; margin-top: 24px; }
.track-tags span { padding: 7px 11px; border: 1px solid currentColor; border-radius: 99px; font-size: .7rem; font-weight: 700; }

.fall-card { background: #f6f0e6; }
.fall-chain { display: grid; gap: 8px; }
.fall-chain > div {
  position: relative;
  min-height: 78px;
  padding: 20px 70px 20px 22px;
  overflow: hidden;
  border: 1px solid rgba(16, 33, 31, .18);
  border-radius: 14px;
  background: rgba(255,255,255,.58);
}
.fall-chain span { color: var(--coral); font: 600 .58rem/1 var(--mono); }
.fall-chain b { display: block; margin-top: 8px; font-size: .88rem; }
.fall-chain i { position: absolute; right: 22px; top: 50%; width: 32px; height: 32px; border: 2px solid var(--ink); border-radius: 50%; transform: translateY(-50%); }
.fall-chain i::after { content: ""; position: absolute; width: 30px; border-top: 2px solid var(--coral); left: -22px; top: 15px; transform: rotate(-18deg); transform-origin: right; }
.fall-chain > div:nth-child(2) i { transform: translateY(-50%) rotate(22deg); }
.fall-chain > div:nth-child(3) i { transform: translateY(-50%) rotate(46deg); }
.fall-chain > div:nth-child(4) { background: var(--coral); color: #fff; border-color: var(--coral); }
.fall-chain > div:nth-child(4) span { color: #ffe1d9; }
.fall-chain > div:nth-child(4) i { border-color: #fff; }
.fall-chain > div:nth-child(5) i { border-color: var(--teal); }

.glp-card { background: #101e1c; color: #edf2ee; }
.glp-card .eyebrow, .glp-card .source { color: #7edaca; }
.glp-card .track-copy > p { color: #b9c6c1; }
.glp-visual { min-height: 500px; padding: 36px; border: 1px solid rgba(255,255,255,.14); border-radius: 24px; background: #172825; }
.glp-orbit { position: relative; width: 260px; height: 260px; margin: 0 auto 36px; display: grid; place-items: center; border: 1px solid rgba(255,255,255,.2); border-radius: 50%; }
.glp-orbit span { font: 600 .68rem/1.35 var(--mono); letter-spacing: .1em; text-align: center; }
.glp-orbit i { position: absolute; inset: 22px; border: 2px solid #7edaca; border-radius: 50%; border-left-color: transparent; transform: rotate(28deg); }
.glp-orbit i:nth-child(2) { inset: 52px; border-color: var(--coral) transparent var(--coral) var(--coral); transform: rotate(-42deg); }
.glp-orbit i:nth-child(3) { inset: 82px; border-color: #fff #fff transparent #fff; transform: rotate(76deg); }
.glp-visual dl { margin: 0; border-top: 1px solid rgba(255,255,255,.14); }
.glp-visual dl div { display: flex; justify-content: space-between; gap: 20px; padding: 13px 0; border-bottom: 1px solid rgba(255,255,255,.14); }
.glp-visual dt { color: #9baba6; font-size: .76rem; }
.glp-visual dd { margin: 0; color: #fff; font: 600 .61rem/1 var(--mono); letter-spacing: .08em; text-transform: uppercase; }
.evidence-note { margin-top: 24px; padding: 18px 0 18px 20px; border-left: 2px solid #7edaca; color: #c3cec9; font-size: .83rem; }
.evidence-note b { color: #fff; }

.music-card { grid-template-columns: .8fr 1.2fr; background: #173dff; color: #fff; }
.music-card .eyebrow { color: #ffb6a5; }
.music-card h3 em { color: #ff9c83; font-weight: 400; }
.music-card .source { color: #fff; }
.license-note { margin: 26px 0 6px; padding: 18px; border: 1px solid rgba(255,255,255,.28); border-radius: 14px; }
.license-note b { display: block; margin-bottom: 6px; font: 600 .58rem/1 var(--mono); letter-spacing: .12em; }
.license-note span { display: block; color: #dbe2ff; font-size: .77rem; }
.rhythm-stage { padding: clamp(26px, 4vw, 52px); border-radius: 24px; background: #f8f5ed; color: var(--ink); box-shadow: 0 28px 70px rgba(5, 16, 74, .28); }
.sound-status { display: flex; justify-content: space-between; gap: 20px; margin-bottom: 28px; padding-bottom: 18px; border-bottom: 1px solid var(--line); }
.sound-status span { color: var(--coral); font: 600 .59rem/1 var(--mono); letter-spacing: .1em; }
.sound-status b { font-size: .75rem; }
.rhythm-row { display: grid; grid-template-columns: 64px 1fr 94px; gap: 14px; align-items: center; min-height: 74px; border-bottom: 1px solid var(--line); }
.rhythm-row > span { font: 700 .7rem/1 var(--sans); }
.rhythm-row > b { color: #66716d; font: 500 .55rem/1.2 var(--mono); text-transform: uppercase; }
.rhythm-row > div { height: 42px; display: flex; align-items: center; justify-content: space-around; gap: 4px; }
.rhythm-row i { display: block; width: 5px; height: 10px; border-radius: 6px; background: #95a09c; }
.walk-rhythm i:nth-child(2n) { height: 18px; }
.bounce-rhythm i { height: 15px; background: var(--teal); }
.bounce-rhythm i:nth-child(3n+2) { height: 32px; }
.stamp-rhythm i { height: 7px; }
.stamp-rhythm i:nth-child(4n+1) { width: 11px; height: 38px; background: var(--coral); }
.jump-rhythm i { height: 6px; }
.jump-rhythm i:nth-child(3), .jump-rhythm i:nth-child(7) { width: 10px; height: 40px; background: var(--blue); }
.rhythm-stage > p { margin: 20px 0 0; color: #6b7672; font: 500 .57rem/1.45 var(--mono); }

@media (max-width: 980px) {
  .frontier-head, .frontier-card, .music-card { grid-template-columns: 1fr; }
  .frontier-head > p:last-child { margin-top: 18px; max-width: 620px; }
  .frontier-card { min-height: 0; }
  .glp-visual { order: 2; }
}

@media (max-width: 600px) {
  .frontier { padding-block: 80px; }
  .frontier-card { padding: 26px 20px; border-radius: 22px; }
  .fall-chain > div { min-height: 70px; }
  .glp-visual { min-height: 0; padding: 24px 18px; }
  .glp-orbit { width: 220px; height: 220px; }
  .rhythm-stage { padding: 22px 16px; }
  .rhythm-row { grid-template-columns: 54px 1fr; }
  .rhythm-row > b { display: none; }
  .sound-status { align-items: flex-start; flex-direction: column; }
}