02Blurred sticky nav

<main class="stage">
  <nav class="navbar">
    <span class="navbar__brand">Vantage</span>
    <div class="navbar__items is-demo">
      <span class="navbar__pill" aria-hidden="true"></span>
      <span class="navbar__item">Home</span>
      <span class="navbar__item">Features</span>
      <span class="navbar__item">Pricing</span>
    </div>
    <button class="navbar__cta" type="button">Start</button>
  </nav>
</main>

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

$duration: $dur-loop;       // 필이 두 항목 사이를 오가는 한 주기
$easing: $ease-spring;
$color: $subject-blue;

@include stage($stage-yellow);

$item-gap: $sp-1;

.navbar {
  --item-w: clamp(32px, 12vw, 64px); // 3개 항목이 320px 폭에서도 브랜드·CTA 와 함께 들어가도록 반응형
  display: flex;
  align-items: center;
  gap: $sp-4;
  width: clamp(240px, 84vw, 380px);
  border-radius: $r-pill;
  background: rgba($subject-ink, .92);
  border: 1px solid rgba($subject-cream, .1);
  box-shadow: $shadow-raised;
  padding: $sp-2 $sp-2 $sp-2 $sp-4;
  backdrop-filter: blur(10px);
}
.navbar__brand {
  flex: 0 0 auto;
  color: $subject-cream;
  font: 700 clamp(12px, 3vw, 14px)/1 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
}
.navbar__items {
  position: relative;
  display: flex;
  gap: $item-gap;
  flex: 1 1 auto;
  background: rgba($subject-cream, .05);
  border-radius: $r-pill;
  padding: $sp-1;
}
.navbar__pill {
  position: absolute;
  left: $sp-1;
  top: $sp-1;
  bottom: $sp-1;
  width: var(--item-w);
  border-radius: $r-pill;
  background: $subject-blue-deep;
  animation: pillMove $duration $easing infinite;
}
.navbar__item {
  position: relative;
  z-index: 1;
  flex: 0 0 var(--item-w);
  width: var(--item-w);
  text-align: center;
  padding: $sp-2 0;
  color: rgba($subject-cream, .9);   // 파란 알약($subject-blue-deep) 위에서 .7 은 3.68:1 이었다 — AA 4.5 (5.10:1)
  font-weight: 600; font-size: clamp(10.5px, 2.6vw, 12px); line-height: 1;
}
.navbar__cta {
  flex: 0 0 auto;
  border: 0;
  border-radius: $r-pill;
  background: $subject-blue-deep;
  color: $subject-cream;
  padding: $sp-2 $sp-4;
  font-weight: 600; font-size: clamp(10.5px, 2.6vw, 12px); line-height: 1;
}

@keyframes pillMove {
  0%, 20%  { transform: translateX(0); }
  50%, 70% { transform: translateX(calc(var(--item-w) + #{$item-gap})); }
  100%     { transform: translateX(0); }
}

@media (prefers-reduced-motion: reduce) {
  .navbar__pill { animation: none !important; transform: translateX(0); }
}

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);
}

.navbar {
  --item-w: clamp(32px, 12vw, 64px);
  display: flex;
  align-items: center;
  gap: 16px;
  width: clamp(240px, 84vw, 380px);
  border-radius: 999px;
  background: rgba(23, 20, 26, 0.92);
  border: 1px solid rgba(255, 247, 230, 0.1);
  box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
  padding: 8px 8px 8px 16px;
  backdrop-filter: blur(10px);
}

.navbar__brand {
  flex: 0 0 auto;
  color: #fff7e6;
  font: 700 clamp(12px, 3vw, 14px)/1 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
}

.navbar__items {
  position: relative;
  display: flex;
  gap: 4px;
  flex: 1 1 auto;
  background: rgba(255, 247, 230, 0.05);
  border-radius: 999px;
  padding: 4px;
}

.navbar__pill {
  position: absolute;
  left: 4px;
  top: 4px;
  bottom: 4px;
  width: var(--item-w);
  border-radius: 999px;
  background: #0a4fe8;
  animation: pillMove 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

.navbar__item {
  position: relative;
  z-index: 1;
  flex: 0 0 var(--item-w);
  width: var(--item-w);
  text-align: center;
  padding: 8px 0;
  color: rgba(255, 247, 230, 0.9);
  font-weight: 600;
  font-size: clamp(10.5px, 2.6vw, 12px);
  line-height: 1;
}

.navbar__cta {
  flex: 0 0 auto;
  border: 0;
  border-radius: 999px;
  background: #0a4fe8;
  color: #fff7e6;
  padding: 8px 16px;
  font-weight: 600;
  font-size: clamp(10.5px, 2.6vw, 12px);
  line-height: 1;
}

@keyframes pillMove {
  0%, 20% {
    transform: translateX(0);
  }
  50%, 70% {
    transform: translateX(calc(var(--item-w) + 4px));
  }
  100% {
    transform: translateX(0);
  }
}
@media (prefers-reduced-motion: reduce) {
  .navbar__pill {
    animation: none !important;
    transform: translateX(0);
  }
}

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

export type NavLinearProps = {
  brand?: string;
  items?: [string, string, string];
  cta?: string;
  /** 필이 두 항목 사이를 오가는 한 주기(기본 2000ms) */
  duration?: number;
  easing?: string;
  color?: string;
};

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

export default function NavLinear({
  brand = "Vantage",
  items = ["홈", "기능", "요금제"],
  cta = "시작",
  duration = 2000,
  easing = "cubic-bezier(.2,1.4,.4,1)",
  color = "#0a4fe8",
}: NavLinearProps) {
  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };

  return (
    <nav className={styles.navbar} style={vars}>
      <span className={styles.brand}>{brand}</span>
      <div className={styles.items}>
        <span className={styles.pill} aria-hidden="true" />
        {items.map((label) => (
          <span key={label} className={styles.item}>{label}</span>
        ))}
      </div>
      <button type="button" className={styles.cta}>{cta}</button>
    </nav>
  );
}