08Diagonal stripe move

<main class="stage">
  <p class="hint">Promo banner</p>
</main>

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

// ── 변수 3개 ──────────────────────────────────────────
$duration: $dur-loop;                                // 줄무늬 한 칸만큼 행진하는 시간
$easing: linear;
$color: $subject-blue;                                // 줄무늬 색

// ── 데모 무대 ──────────────────────────────────────────
@include stage($stage-paper);

.stage {
  position: relative;
  overflow: hidden;
}

// 세로 줄무늬를 그린 뒤 통째로 45도 회전시켜 대각선으로 보이게 하고, background-position 은 회전 전 좌표계에서 가로로만 한 칸(36px) 이동시킨다
// (45deg 로 기울인 채로 background-position 을 대각선으로 움직이면 이동 방향이 줄무늬와 나란해져 화면이 안 바뀐다 — 실측 2026-09-09)
.stage::before {
  content: "";
  position: absolute;
  inset: -150% -150%;
  transform: rotate(45deg);
  background-image: repeating-linear-gradient(90deg, rgba($color, .18) 0 18px, transparent 18px 36px);
  animation: stripemove $duration $easing infinite;
}

.hint {
  position: relative;
  margin: 0;
  padding: 10px 20px;
  border-radius: $r-pill;
  background: rgba($stage-ink, .08);
  color: $stage-ink;
  font: 700 clamp(14px, 4vw, 18px)/1.3 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
}

@keyframes stripemove {
  from { background-position: 0 0; }
  to   { background-position: 36px 0; }
}

@media (prefers-reduced-motion: reduce) {
  .stage::before { animation: none; }
}

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

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

.stage {
  position: relative;
  overflow: hidden;
}

.stage::before {
  content: "";
  position: absolute;
  inset: -150% -150%;
  transform: rotate(45deg);
  background-image: repeating-linear-gradient(90deg, rgba(47, 109, 246, 0.18) 0 18px, transparent 18px 36px);
  animation: stripemove 2s linear infinite;
}

.hint {
  position: relative;
  margin: 0;
  padding: 10px 20px;
  border-radius: 999px;
  background: rgba(23, 20, 26, 0.08);
  color: #17141a;
  font: 700 clamp(14px, 4vw, 18px)/1.3 -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
}

@keyframes stripemove {
  from {
    background-position: 0 0;
  }
  to {
    background-position: 36px 0;
  }
}
@media (prefers-reduced-motion: reduce) {
  .stage::before {
    animation: none;
  }
}

import type { CSSProperties, ReactNode } from "react";
import styles from "./StripesDiagonalBg.module.scss";

export type StripesDiagonalBgProps = {
  children?: ReactNode;
  /** 줄무늬 한 칸만큼 행진하는 시간 (기본 2000ms) */
  duration?: number;
  /** 줄무늬 색 */
  color?: string;
  className?: string;
};

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

export default function StripesDiagonalBg({
  children,
  duration = 2000,
  color = "#2f6df6",
  className = "",
}: StripesDiagonalBgProps) {
  const vars: Vars = { "--duration": `${duration}ms`, "--color": color };
  return (
    <div className={`${styles.stage} ${className}`} style={vars}>
      <div className={styles.stripes} aria-hidden="true" />
      {children}
    </div>
  );
}