03角丸値の成長 — 開く値が大きくなるほどボタンの角の丸み値が一緒に大きくなる方式

<main class="stage">
<div class="cr is-demo" id="cr">
  <div class="cr__meter" aria-hidden="true">
    <div class="cr__meterFill" id="crFill"></div>
  </div>
  <p class="cr__read" id="crRead">丸み値 12px</p>
  <div class="cr__btn" id="crBtn" role="button" tabindex="0" aria-label="段階値を上げる">
    <span class="cr__label">次の段階</span>
  </div>
  <div class="cr__steps" aria-hidden="true">
    <span class="cr__dot"></span>
    <span class="cr__dot"></span>
    <span class="cr__dot"></span>
    <span class="cr__dot"></span>
  </div>
</div>
</main>

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

// 계산 겹: 단계 값마다 둥근 반경이 RADII 산술(12→16→24→알약)으로 커지고(index.html),
// 크기 성장 곡선이 같은 transition 에 물려 함께 이어진다.
@include stage($stage-orange);

.cr {
  display: grid;
  gap: $sp-4;
  justify-items: center;
}

.cr__meter {
  width: 220px;
  height: $sp-1;
  border-radius: $r-xs;
  background: rgba($subject-cream, .22);
  overflow: hidden;
}

.cr__meterFill {
  width: 100%;
  height: 100%;
  border-radius: $r-xs;
  background: $subject-cream;
  transform-origin: left center;
  transform: scaleX(.25);
  transition: transform $dur-base $ease-out;
}

.cr__read {
  margin: 0;
  color: $subject-ink;
  font-size: 13px;
  font-weight: 600;
}

.cr__btn {
  display: grid;
  place-items: center;
  width: 200px;
  height: 64px;
  border-radius: $r-control;
  background: $stage-paper;
  color: $subject-ink;
  box-shadow: $shadow-raised;
  cursor: pointer;
  transition: border-radius $dur-enter $ease-elastic, width $dur-enter $ease-elastic, height $dur-enter $ease-elastic;
}

.cr__label {
  font-weight: 700;
  font-size: 16px;
}

.cr__steps {
  display: flex;
  gap: $sp-2;
}

.cr__dot {
  width: $sp-2;
  height: $sp-2;
  border-radius: 50%;
  background: rgba($subject-cream, .28);
  transition: background-color $dur-quick $ease-out, transform $dur-quick $ease-elastic;
}

.cr__dot--on {
  background: $stage-paper;
  transform: scale(1.18);
}

@media (max-width: 340px) {
  .cr__btn { width: 180px; height: 56px; }
  .cr__meter { width: 180px; }
}

@media (prefers-reduced-motion: reduce) {
  .cr__btn, .cr__meterFill, .cr__dot { transition: none; }
}

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

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ff4d1f;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.cr {
  display: grid;
  gap: 16px;
  justify-items: center;
}

.cr__meter {
  width: 220px;
  height: 4px;
  border-radius: 4px;
  background: rgba(255, 247, 230, 0.22);
  overflow: hidden;
}

.cr__meterFill {
  width: 100%;
  height: 100%;
  border-radius: 4px;
  background: #fff7e6;
  transform-origin: left center;
  transform: scaleX(0.25);
  transition: transform 300ms ease-out;
}

.cr__read {
  margin: 0;
  color: #17141a;
  font-size: 13px;
  font-weight: 600;
}

.cr__btn {
  display: grid;
  place-items: center;
  width: 200px;
  height: 64px;
  border-radius: 12px;
  background: #ffffff;
  color: #17141a;
  box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
  cursor: pointer;
  transition: border-radius 600ms cubic-bezier(0.34, 1.56, 0.64, 1), width 600ms cubic-bezier(0.34, 1.56, 0.64, 1), height 600ms cubic-bezier(0.34, 1.56, 0.64, 1);
}

.cr__label {
  font-weight: 700;
  font-size: 16px;
}

.cr__steps {
  display: flex;
  gap: 8px;
}

.cr__dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: rgba(255, 247, 230, 0.28);
  transition: background-color 220ms ease-out, transform 220ms cubic-bezier(0.34, 1.56, 0.64, 1);
}

.cr__dot--on {
  background: #ffffff;
  transform: scale(1.18);
}

@media (max-width: 340px) {
  .cr__btn {
    width: 180px;
    height: 56px;
  }
  .cr__meter {
    width: 180px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .cr__btn, .cr__meterFill, .cr__dot {
    transition: none;
  }
}

(function () {
  var root = document.getElementById('cr');
  var btn = document.getElementById('crBtn');
  var fill = document.getElementById('crFill');
  var read = document.getElementById('crRead');
  var dots = root.querySelectorAll('.cr__dot');
  var RADII = [12, 16, 24, 999]; // 계산 겹: 단계마다 커지는 둥근 값(px) — 마지막은 ピル
  var RADII_TEXT = ['丸み値 12px', '丸み値 16px', '丸み値 24px', '丸み値 ピル'];
  var step = 0;

  function paint() {
    var r = RADII[step];
    // 둥근 값은 % 가 아니라 px 로 보간해야 성장이 선형으로 보인다 — 999px 는 ピル 표기
    btn.style.borderRadius = (r === 999 ? '999px' : r + 'px');
    read.textContent = RADII_TEXT[step];
    fill.style.transform = 'scaleX(' + ((step + 1) / RADII.length) + ')';
    dots.forEach(function (d, i) {
      d.classList.toggle('cr__dot--on', i <= step);
    });
  }

  function advance() {
    step = (step + 1) % RADII.length;
    paint();
  }

  function human() {
    root.classList.remove('is-demo');
    stopAutoplay();
    advance();
  }
  btn.addEventListener('click', human);
  btn.addEventListener('keydown', function (e) {
    if (e.key === 'Enter' || e.key === ' ') { e.preventDefault(); human(); }
  });

  var autoTimer = null;
  function stopAutoplay() { if (autoTimer) { clearInterval(autoTimer); autoTimer = null; } }
  var reduce = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
  paint();
  if (!reduce) { autoTimer = setInterval(advance, 900); }
})();

import { useEffect, useRef } from "react";
import styles from "./CornerRoundGrow.module.scss";

type Box<T> = { current: T };

const RADII = [12, 16, 24, 999]; // 계산 겹: 단계마다 커지는 둥근 값(px) — 마지막은 알약
const RADII_TEXT = ["둥근 값 12px", "둥근 값 16px", "둥근 값 24px", "둥근 값 알약"];

export default function CornerRoundGrow() {
  const rootRef = useRef(null) as unknown as Box<HTMLDivElement | null>;

  useEffect(() => {
    const root = rootRef.current;
    if (!root) return;
    const btn = root.querySelector(`.${styles.btn}`) as HTMLElement | null;
    const fill = root.querySelector(`.${styles.fill}`) as HTMLElement | null;
    const read = root.querySelector(`.${styles.read}`) as HTMLElement | null;
    const dots = root.querySelectorAll(`.${styles.dot}`);
    if (!btn || !fill || !read) return;

    let step = 0;

    function paint() {
      const r = RADII[step];
      btn!.style.borderRadius = (r === 999 ? "999px" : r + "px");
      read!.textContent = RADII_TEXT[step];
      fill!.style.transform = "scaleX(" + ((step + 1) / RADII.length) + ")";
      dots.forEach((d, i) => {
        d.classList.toggle(styles["dot--on"], i <= step);
      });
    }

    function advance() {
      step = (step + 1) % RADII.length;
      paint();
    }

    function human() {
      root!.classList.remove(styles["is-demo"]);
      stopAutoplay();
      advance();
    }
    function onClick() { human(); }
    function onKey(e: KeyboardEvent) {
      if (e.key === "Enter" || e.key === " ") { e.preventDefault(); human(); }
    }
    btn.addEventListener("click", onClick);
    btn.addEventListener("keydown", onKey);

    let autoTimer: number | null = null;
    function stopAutoplay() { if (autoTimer !== null) { window.clearInterval(autoTimer); autoTimer = null; } }
    const reduce = window.matchMedia("(prefers-reduced-motion: reduce)").matches;
    paint();
    if (!reduce) { autoTimer = window.setInterval(advance, 900); }

    return () => {
      stopAutoplay();
      btn.removeEventListener("click", onClick);
      btn.removeEventListener("keydown", onKey);
    };
  }, []);

  return (
    <div ref={rootRef} className={`${styles.stage} ${styles.cr} ${styles["is-demo"]}`}>
      <div className={styles.meter} aria-hidden="true">
        <div className={styles.fill} />
      </div>
      <p className={styles.read}>둥근 값 12px</p>
      <div className={styles.btn} role="button" tabIndex={0} aria-label="단계 값 올리기">
        <span className={styles.label}>다음 단계</span>
      </div>
      <div className={styles.steps} aria-hidden="true">
        <span className={styles.dot} />
        <span className={styles.dot} />
        <span className={styles.dot} />
        <span className={styles.dot} />
      </div>
    </div>
  );
}