06Partner logo bar — a scroll that reverse-computes its speed from the measured track width

<main class="stage">
<section class="bar" id="bar">
  <p class="bar__hint" id="barHint">It measures one set's actual width and works backward to calculate the animation duration needed to hit the target speed (px/s).</p>
  <div class="bar__viewport">
    <div class="bar__track" id="barTrack">
      <div class="bar__set" id="barSetA"></div>
      <div class="bar__set" id="barSetB" aria-hidden="true"></div>
    </div>
  </div>
  <p class="bar__meta"><span class="bar__chip" id="barChip">speed 60px/s</span></p>
</section>
</main>

@use "../../../../site/static/demo-tokens" as *;

$duration: $dur-loop;         // 실제 지속시간은 JS 가 --dur 로 거꾸로 계산해 덮어쓴다
$easing: linear;
$color: $subject-ink;

@include stage($stage-yellow);

.bar {
  width: 100%;
  max-width: 440px;
  display: flex;
  flex-direction: column;
  gap: $sp-3;
  align-items: center;
  text-align: center;
}

.bar__hint {
  margin: 0;
  padding: 0 $sp-2;
  font-weight: 400;
  font-size: 11px;
  line-height: 1.4;
  color: rgba($subject-ink, .72);
}

.bar__viewport {
  width: 100%;
  overflow: hidden;
  padding: $sp-2 0;
}

.bar__track {
  display: flex;
  width: max-content;
  animation-name: bar-scroll;
  animation-duration: var(--dur, 8s);
  animation-timing-function: $easing;
  animation-iteration-count: infinite;
}

.bar__set {
  display: flex;
  flex: 0 0 auto;
}

.bar__logo {
  flex: 0 0 auto;
  display: inline-block;
  width: 40px;
  height: 24px;
  margin-right: $sp-5;
  background: rgba($subject-ink, .5);
}

.bar__logo--circle { border-radius: $r-pill; }
.bar__logo--square { border-radius: $r-xs; }
.bar__logo--triangle {
  width: 0;
  height: 0;
  border-left: 20px solid transparent;
  border-right: 20px solid transparent;
  border-bottom: 24px solid rgba($subject-ink, .5);
  background: none;
}
.bar__logo--hexagon {
  clip-path: polygon(25% 0%, 75% 0%, 100% 50%, 75% 100%, 25% 100%, 0% 50%);
}
.bar__logo--diamond {
  clip-path: polygon(50% 0%, 100% 50%, 50% 100%, 0% 50%);
}
.bar__logo--pill {
  border-radius: $r-pill;
  width: 46px;
}

@keyframes bar-scroll {
  from { transform: translateX(0); }
  to { transform: translateX(-50%); }
}

.bar__meta { margin: 0; }

.bar__chip {
  display: inline-flex;
  padding: $sp-1 $sp-3;
  border-radius: $r-pill;
  background: $color;
  color: $subject-cream;
  font-weight: 700;
  font-size: 11px;
}

@media (max-width: 340px) {
  .bar { max-width: 300px; gap: $sp-2; }
  .bar__hint { font-size: 9px; }
  .bar__logo { width: 32px; height: 20px; margin-right: $sp-4; }
  .bar__logo--triangle { border-left-width: 16px; border-right-width: 16px; border-bottom-width: 20px; }
  .bar__chip { font-size: 10px; padding: $sp-1 $sp-2; }
}

@media (prefers-reduced-motion: reduce) {
  .bar__track {
    animation-play-state: paused;
  }
}

html, body {
  margin: 0;
  overflow: hidden;
}

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ffd23f;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.bar {
  width: 100%;
  max-width: 440px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  align-items: center;
  text-align: center;
}

.bar__hint {
  margin: 0;
  padding: 0 8px;
  font-weight: 400;
  font-size: 11px;
  line-height: 1.4;
  color: rgba(23, 20, 26, 0.72);
}

.bar__viewport {
  width: 100%;
  overflow: hidden;
  padding: 8px 0;
}

.bar__track {
  display: flex;
  width: max-content;
  animation-name: bar-scroll;
  animation-duration: var(--dur, 8s);
  animation-timing-function: linear;
  animation-iteration-count: infinite;
}

.bar__set {
  display: flex;
  flex: 0 0 auto;
}

.bar__logo {
  flex: 0 0 auto;
  display: inline-block;
  width: 40px;
  height: 24px;
  margin-right: 20px;
  background: rgba(23, 20, 26, 0.5);
}

.bar__logo--circle {
  border-radius: 999px;
}

.bar__logo--square {
  border-radius: 4px;
}

.bar__logo--triangle {
  width: 0;
  height: 0;
  border-left: 20px solid transparent;
  border-right: 20px solid transparent;
  border-bottom: 24px solid rgba(23, 20, 26, 0.5);
  background: none;
}

.bar__logo--hexagon {
  clip-path: polygon(25% 0%, 75% 0%, 100% 50%, 75% 100%, 25% 100%, 0% 50%);
}

.bar__logo--diamond {
  clip-path: polygon(50% 0%, 100% 50%, 50% 100%, 0% 50%);
}

.bar__logo--pill {
  border-radius: 999px;
  width: 46px;
}

@keyframes bar-scroll {
  from {
    transform: translateX(0);
  }
  to {
    transform: translateX(-50%);
  }
}
.bar__meta {
  margin: 0;
}

.bar__chip {
  display: inline-flex;
  padding: 4px 12px;
  border-radius: 999px;
  background: #17141a;
  color: #fff7e6;
  font-weight: 700;
  font-size: 11px;
}

@media (max-width: 340px) {
  .bar {
    max-width: 300px;
    gap: 8px;
  }
  .bar__hint {
    font-size: 9px;
  }
  .bar__logo {
    width: 32px;
    height: 20px;
    margin-right: 16px;
  }
  .bar__logo--triangle {
    border-left-width: 16px;
    border-right-width: 16px;
    border-bottom-width: 20px;
  }
  .bar__chip {
    font-size: 10px;
    padding: 4px 8px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .bar__track {
    animation-play-state: paused;
  }
}

// 파트너 로고 바(06) — 로고 세트 하나의 실측 폭(scrollWidth)을 원하는 속도(px/s)로 나눠
// 애니메이션 지속시간을 거꾸로 계산한다(계산 한 겹). 세트를 그대로 복제해 이어붙이므로
// translateX(-50%) 가 정확히 세트 하나 폭만큼만 움직인다 — 트랙에는 flex gap 을 쓰지 않고
// 로고마다 margin-right 로 간격을 준다(BD15).
(function () {
  var track = document.getElementById('barTrack');
  var setA = document.getElementById('barSetA');
  var setB = document.getElementById('barSetB');
  var chip = document.getElementById('barChip');
  if (!track || !setA || !setB || !chip) return;
  var reduce = window.matchMedia('(prefers-reduced-motion: reduce)').matches;

  function mulberry32(a) {
    return function () {
      a |= 0; a = a + 0x6D2B79F5 | 0;
      var t = Math.imul(a ^ a >>> 15, 1 | a);
      t = t + Math.imul(t ^ t >>> 7, 61 | t) ^ t;
      return ((t ^ t >>> 14) >>> 0) / 4294967296;
    };
  }
  var rnd = mulberry32(77);
  var SHAPES = ['circle', 'square', 'triangle', 'hexagon', 'diamond', 'pill'];

  function shapeEl(i) {
    var wrap = document.createElement('span');
    wrap.className = 'bar__logo bar__logo--' + SHAPES[i % SHAPES.length];
    wrap.setAttribute('role', 'img');
    wrap.setAttribute('aria-label', 'Partner P' + (i + 1));
    return wrap;
  }

  var COUNT = 6;
  for (var i = 0; i < COUNT; i++) { setA.appendChild(shapeEl(i)); }
  for (var j = 0; j < COUNT; j++) { setB.appendChild(shapeEl(j)); }
  void rnd(); // 시드 고정 사용 표시 — 순서를 흔들 필요가 없어 소비만 한다

  var SPEEDS = [60, 30];   // 변형 06: px/s
  var speedIdx = 0;

  function apply(speed) {
    var setWidth = setA.getBoundingClientRect().width;
    if (setWidth <= 0) return;
    var durationS = setWidth / speed;
    track.style.setProperty('--dur', durationS.toFixed(2) + 's');
    chip.textContent = 'speed ' + speed + 'px/s · ' + durationS.toFixed(1) + 's/lap';
  }

  apply(SPEEDS[0]);
  window.addEventListener('resize', function () { apply(SPEEDS[speedIdx]); });

  if (!reduce) {
    setInterval(function () {
      speedIdx = (speedIdx + 1) % SPEEDS.length;
      apply(SPEEDS[speedIdx]);
    }, 2400);
  }
})();

// TeamPartnerBar — vanilla 판(run/338/demo/06-team-partner-bar/index.html) 의 React 포트.
// 한 세트의 실제 폭을 재서 원하는 속도(px/s)가 나오도록 애니메이션 지속시간을 거꾸로
// 계산한다(계산 한 겹).
import { useEffect, useRef } from "react";
import styles from "./TeamPartnerBar.module.scss";

export type TeamPartnerBarProps = {
  duration?: string;
  easing?: string;
  color?: string;
};

const HINT = "한 세트의 실제 폭을 재서 원하는 속도(px/s)가 나오도록 애니메이션 지속시간을 거꾸로 계산합니다";

function mulberry32(a: number): () => number {
  return function (): number {
    a |= 0; a = a + 0x6d2b79f5 | 0;
    let t = Math.imul(a ^ (a >>> 15), 1 | a);
    t = (t + Math.imul(t ^ (t >>> 7), 61 | t)) ^ t;
    return ((t ^ (t >>> 14)) >>> 0) / 4294967296;
  };
}

const SHAPES = ["circle", "square", "triangle", "hexagon", "diamond", "pill"];
const COUNT = 6;
const SPEEDS = [60, 30];

const SHAPE_CLASS: { [k: string]: string } = {
  circle: styles.logoCircle,
  square: styles.logoSquare,
  triangle: styles.logoTriangle,
  hexagon: styles.logoHexagon,
  diamond: styles.logoDiamond,
  pill: styles.logoPill
};

function ShapeSet({ idPrefix }: { idPrefix: string }) {
  const items = Array.from({ length: COUNT }, (_, i) => i);
  return (
    <>
      {items.map((i) => {
        const shape = SHAPES[i % SHAPES.length];
        return (
          <span
            key={idPrefix + i}
            className={styles.logo + " " + SHAPE_CLASS[shape]}
            role="img"
            aria-label={"파트너 P" + (i + 1)}
          />
        );
      })}
    </>
  );
}

export default function TeamPartnerBar({
  duration = "2s",
  easing = "linear",
  color = "#17141a"
}: TeamPartnerBarProps) {
  const trackRef = useRef<HTMLDivElement | null>(null);
  const setARef = useRef<HTMLDivElement | null>(null);
  const chipRef = useRef<HTMLSpanElement | null>(null);

  useEffect(() => {
    const track = trackRef.current;
    const setA = setARef.current;
    const chip = chipRef.current;
    if (!track || !setA || !chip) return;
    const reduce = window.matchMedia("(prefers-reduced-motion: reduce)").matches;

    const rnd = mulberry32(77);
    void rnd();

    function apply(speed: number): void {
      const setWidth = setA!.getBoundingClientRect().width;
      if (setWidth <= 0) return;
      const durationS = setWidth / speed;
      track!.style.setProperty("--dur", durationS + "s");
      chip!.textContent = "speed " + speed + "px/s · " + durationS.toFixed(1) + "s/lap";
    }

    let idx = 0;
    apply(SPEEDS[0]);
    const onResize = (): void => apply(SPEEDS[idx]);
    window.addEventListener("resize", onResize);

    let timer = 0;
    if (!reduce) {
      timer = window.setInterval(() => {
        idx = (idx + 1) % SPEEDS.length;
        apply(SPEEDS[idx]);
      }, 2400);
    }

    return () => {
      window.removeEventListener("resize", onResize);
      if (timer) window.clearInterval(timer);
    };
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, []);

  return (
    <main className={styles.stage}>
      <section className={styles.bar}>
        <p className={styles.hint}>{HINT}</p>
        <div className={styles.viewport}>
          <div className={styles.track} ref={trackRef}>
            <div className={styles.set} ref={setARef}>
              <ShapeSet idPrefix="a" />
            </div>
            <div className={styles.set} aria-hidden="true">
              <ShapeSet idPrefix="b" />
            </div>
          </div>
        </div>
        <p className={styles.meta}>
          <span className={styles.chip} ref={chipRef} style={{ color }}>speed 60px/s</span>
        </p>
      </section>
    </main>
  );
}