02Jelly indicator nav

<main class="stage">
  <nav class="navcandy" aria-label="Main menu">
    <span class="navcandy__brand">Pudding</span>
    <div class="navcandy__track">
      <span class="navcandy__pill" aria-hidden="true"></span>
      <span class="navcandy__tab navcandy__tab--on">Home</span>
      <span class="navcandy__tab">Features</span>
      <span class="navcandy__tab">Pricing</span>
      <span class="navcandy__tab">Contact</span>
    </div>
    <button class="navcandy__cta" type="button">Get started</button>
  </nav>
</main>

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

$duration: $dur-loop;       // 알약이 네 칸을 한 바퀴 도는 주기
$easing: $ease-spring;      // 도착할 때 통통하게 줄어드는 곡선
$color: $stage-ink;         // 글자 기본(토큰) — 아래 베리 잉크로 덮는다

// 캔디 팔레트 — 값은 tailwind.config.js · tokens.css 와 같다
$candy-cream:    #fff6f0;
$candy-bubble:   #ffb9cf;
$candy-lavender: #cdbcf2;
$candy-mint:     #b5e8d2;
$candy-berry:    #55395e;

// 무대 — 라벤더 물색
@include stage(mix($candy-lavender, $stage-paper, 30%));

.navcandy {
  box-sizing: border-box;
  width: clamp(280px, 92vw, 440px);
  display: flex;
  align-items: center;
  gap: $sp-2;
  padding: $sp-2;
  border-radius: $r-pill;
  background: $stage-paper;
  box-shadow: 0 8px 20px rgba($candy-lavender, .55);
}
.navcandy__brand {
  flex: 0 0 auto;
  padding-left: $sp-3;
  color: $candy-berry;
  font-weight: 700; font-size: clamp(11px, 2.6vw, 13px); line-height: 1;
}
.navcandy__track {
  position: relative;
  flex: 1 1 auto;
  min-width: 0;
  display: flex;
  border-radius: $r-pill;
  background: mix($candy-cream, $stage-paper, 60%);
}
.navcandy__pill {
  position: absolute;
  top: $sp-1;
  bottom: $sp-1;
  left: $sp-1;
  width: calc(25% - $sp-1);
  box-sizing: border-box;
  border-radius: $r-pill;
  background: $candy-mint;
  box-shadow: 0 4px 10px rgba($candy-mint, .9);
  // 네 칸을 순서대로 옮겨 다니며 도착할 때마다 젤리처럼 세로로 살짝 눌린다
  animation: pillWalk $duration $easing infinite;
}
.navcandy__tab {
  position: relative;
  z-index: 1;
  flex: 1 1 auto;
  min-width: 0;
  padding: $sp-2 0;
  text-align: center;
  color: rgba($candy-berry, .78);
  font-weight: 600; font-size: clamp(10px, 2.4vw, 12px); line-height: 1;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.navcandy__tab--on {
  color: $candy-berry;
  font-weight: 700;
}
.navcandy__cta {
  flex: 0 0 auto;
  border: 0;
  border-radius: $r-pill;
  background: $candy-bubble;
  color: $candy-berry;
  padding: $sp-2 $sp-4;
  font-weight: 700; font-size: clamp(10px, 2.4vw, 12px); line-height: 1;
  box-shadow: 0 5px 12px rgba($candy-bubble, .7);
}
.navcandy__cta:focus-visible {
  outline: 3px solid $candy-berry;
  outline-offset: 2px;
}

// 데모: 칸 폭은 25% — translateX(100%) 가 정확히 한 칸. 도착 순간 scaleY 로 눌렸다 펴진다
// 데모: % 이동은 이 요소 자기 폭 기준 — 폭이 calc(25% - 4px) 라 한 칸(트랙의 25%)보다 4px 모자라
// 이동량을 calc(100% + 4px) 씩 보정한다(보정 없으면 세 칸을 지나며 12px 밀린다 — 실측)
@keyframes pillWalk {
  0%, 24%   { transform: translateX(0) scaleY(1); }
  30%       { transform: translateX(0) scaleY(.82); }
  36%, 49%  { transform: translateX(calc(100% + 4px)) scaleY(1); }
  55%       { transform: translateX(calc(100% + 4px)) scaleY(.82); }
  61%, 74%  { transform: translateX(calc(200% + 8px)) scaleY(1); }
  80%       { transform: translateX(calc(200% + 8px)) scaleY(.82); }
  86%, 100% { transform: translateX(calc(300% + 12px)) scaleY(1); }
}

@media (prefers-reduced-motion: reduce) {
  .navcandy__pill { animation: none !important; transform: none; }
}

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

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: rgb(94.1176470588%, 92.1176470588%, 98.4705882353%);
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.navcandy {
  box-sizing: border-box;
  width: clamp(280px, 92vw, 440px);
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px;
  border-radius: 999px;
  background: #ffffff;
  box-shadow: 0 8px 20px rgba(205, 188, 242, 0.55);
}

.navcandy__brand {
  flex: 0 0 auto;
  padding-left: 12px;
  color: #55395e;
  font-weight: 700;
  font-size: clamp(11px, 2.6vw, 13px);
  line-height: 1;
}

.navcandy__track {
  position: relative;
  flex: 1 1 auto;
  min-width: 0;
  display: flex;
  border-radius: 999px;
  background: rgb(100%, 97.8823529412%, 96.4705882353%);
}

.navcandy__pill {
  position: absolute;
  top: 4px;
  bottom: 4px;
  left: 4px;
  width: calc(25% - 4px);
  box-sizing: border-box;
  border-radius: 999px;
  background: #b5e8d2;
  box-shadow: 0 4px 10px rgba(181, 232, 210, 0.9);
  animation: pillWalk 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

.navcandy__tab {
  position: relative;
  z-index: 1;
  flex: 1 1 auto;
  min-width: 0;
  padding: 8px 0;
  text-align: center;
  color: rgba(85, 57, 94, 0.78);
  font-weight: 600;
  font-size: clamp(10px, 2.4vw, 12px);
  line-height: 1;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.navcandy__tab--on {
  color: #55395e;
  font-weight: 700;
}

.navcandy__cta {
  flex: 0 0 auto;
  border: 0;
  border-radius: 999px;
  background: #ffb9cf;
  color: #55395e;
  padding: 8px 16px;
  font-weight: 700;
  font-size: clamp(10px, 2.4vw, 12px);
  line-height: 1;
  box-shadow: 0 5px 12px rgba(255, 185, 207, 0.7);
}

.navcandy__cta:focus-visible {
  outline: 3px solid #55395e;
  outline-offset: 2px;
}

@keyframes pillWalk {
  0%, 24% {
    transform: translateX(0) scaleY(1);
  }
  30% {
    transform: translateX(0) scaleY(0.82);
  }
  36%, 49% {
    transform: translateX(calc(100% + 4px)) scaleY(1);
  }
  55% {
    transform: translateX(calc(100% + 4px)) scaleY(0.82);
  }
  61%, 74% {
    transform: translateX(calc(200% + 8px)) scaleY(1);
  }
  80% {
    transform: translateX(calc(200% + 8px)) scaleY(0.82);
  }
  86%, 100% {
    transform: translateX(calc(300% + 12px)) scaleY(1);
  }
}
@media (prefers-reduced-motion: reduce) {
  .navcandy__pill {
    animation: none !important;
    transform: none;
  }
}

import type { CSSProperties } from "react";
import styles from "./NavCandy.module.scss";

export type NavCandyProps = {
  brand?: string;
  tabs?: string[];
  cta?: string;
  /** 한 주기(기본 2000ms) */
  duration?: number;
  easing?: string;
  color?: string;
};

type Vars = CSSProperties & { "--duration"?: string; "--easing"?: string; "--color"?: string };

export default function NavCandy({
  brand = "푸딩",
  tabs = ["홈", "기능", "요금제", "문의"],
  cta = "시작하기",
  duration = 2000,
  easing = "cubic-bezier(.2,.8,.2,1)",
  color = "#b5e8d2",
}: NavCandyProps) {
  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };

  return (
    <nav className={styles.navcandy} aria-label="주요 메뉴" style={vars}>
      <span className={styles.brand}>{brand}</span>
      <div className={styles.track}>
        <span className={styles.pill} aria-hidden="true" />
        {tabs.map((t, i) => (
          <span key={t} className={`${styles.tab} ${i === 0 ? styles.tabOn : ""}`}>{t}</span>
        ))}
      </div>
      <button type="button" className={styles.cta}>{cta}</button>
    </nav>
  );
}