05Orbit dots

<main class="stage">
  <div class="ob-system is-demo" aria-hidden="true">
    <span class="ob-core"></span>
    <span class="ob-dot od-s"></span>
    <span class="ob-dot od-m"></span>
    <span class="ob-dot od-l"></span>
  </div>
</main>

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

// ── 변수 3개 ──────────────────────────────────────────
$duration: 2s;      // 바깥 두 점의 한 바퀴 (안쪽 작은 점은 절반)
$easing: linear;
$color: $subject-cream;

@include stage($stage-ink);

// 실사용: 로딩 중에만 .is-loading
// 각 점은 자기 transform-origin 을 계통 중심에 두고 제자리에서 공전한다.
// 회전하는 컨다란 팔 박스를 쓰면 정사각형이 45도에 경계 상자가 루트2배로
// 커져 320px 폰 화면에서 세로 넘침을 일으킨다 (219 실측).
.ob-system {
  position: relative;
  width: 168px;
  height: 168px;
}

.ob-core {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 24px;
  height: 24px;
  margin: -12px 0 0 -12px;
  border-radius: 50%;
  background: $subject-sky;
}

.ob-dot {
  position: absolute;
  border-radius: 50%;
}

// 작은 점: 안쪽 궤도(반지름 52), 빠르게
.od-s {
  top: 26px;                    // 84 - 52 - 6
  left: calc(50% - 6px);
  width: 12px;
  height: 12px;
  background: $color;
  transform-origin: 50% 58px;   // 점 중심에서 계통 중심까지 52 + 자기 반지름 6
}

// 중간 점: 가장 안쪽 궤도(반지름 36)
.od-m {
  top: 39px;                    // 84 - 36 - 9
  left: calc(50% - 9px);
  width: 18px;
  height: 18px;
  background: $subject-pink;
  transform-origin: 50% 45px; // 규칙8: 계통 중심 공전 축
}

// 큰 점: 바깥 궤도(반지름 68), 느리게
.od-l {
  top: 3px;                     // 84 - 68 - 13
  left: calc(50% - 13px);
  width: 26px;
  height: 26px;
  background: $subject-mint;
  transform-origin: 50% 81px; // 규칙8: 계통 중심 공전 축
}

// 세 점은 같은 방향, 서로 120도씩 어긋난 위상에서 출발한다
.ob-system.is-loading .od-s,
.ob-system.is-demo .od-s { animation: ob-spin-a ($duration / 2) $easing infinite; }
.ob-system.is-loading .od-m,
.ob-system.is-demo .od-m { animation: ob-spin-b $duration $easing infinite; }
.ob-system.is-loading .od-l,
.ob-system.is-demo .od-l { animation: ob-spin-c $duration $easing infinite; }

@keyframes ob-spin-a {
  from { transform: rotate(0deg); }
  to   { transform: rotate(360deg); }
}

@keyframes ob-spin-b {
  from { transform: rotate(120deg); }
  to   { transform: rotate(480deg); }
}

@keyframes ob-spin-c {
  from { transform: rotate(240deg); }
  to   { transform: rotate(600deg); }
}

@media (prefers-reduced-motion: reduce) {
  .ob-system.is-loading .od-s,
  .ob-system.is-loading .od-m,
  .ob-system.is-loading .od-l,
  .ob-system.is-demo .od-s,
  .ob-system.is-demo .od-m,
  .ob-system.is-demo .od-l {
    animation: none !important;
    transform: none !important;
  }
}

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

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #17141a;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.ob-system {
  position: relative;
  width: 168px;
  height: 168px;
}

.ob-core {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 24px;
  height: 24px;
  margin: -12px 0 0 -12px;
  border-radius: 50%;
  background: #6ec8ff;
}

.ob-dot {
  position: absolute;
  border-radius: 50%;
}

.od-s {
  top: 26px;
  left: calc(50% - 6px);
  width: 12px;
  height: 12px;
  background: #fff7e6;
  transform-origin: 50% 58px;
}

.od-m {
  top: 39px;
  left: calc(50% - 9px);
  width: 18px;
  height: 18px;
  background: #ff9ebb;
  transform-origin: 50% 45px;
}

.od-l {
  top: 3px;
  left: calc(50% - 13px);
  width: 26px;
  height: 26px;
  background: #4cd4a6;
  transform-origin: 50% 81px;
}

.ob-system.is-loading .od-s,
.ob-system.is-demo .od-s {
  animation: ob-spin-a 1s linear infinite;
}

.ob-system.is-loading .od-m,
.ob-system.is-demo .od-m {
  animation: ob-spin-b 2s linear infinite;
}

.ob-system.is-loading .od-l,
.ob-system.is-demo .od-l {
  animation: ob-spin-c 2s linear infinite;
}

@keyframes ob-spin-a {
  from {
    transform: rotate(0deg);
  }
  to {
    transform: rotate(360deg);
  }
}
@keyframes ob-spin-b {
  from {
    transform: rotate(120deg);
  }
  to {
    transform: rotate(480deg);
  }
}
@keyframes ob-spin-c {
  from {
    transform: rotate(240deg);
  }
  to {
    transform: rotate(600deg);
  }
}
@media (prefers-reduced-motion: reduce) {
  .ob-system.is-loading .od-s,
  .ob-system.is-loading .od-m,
  .ob-system.is-loading .od-l,
  .ob-system.is-demo .od-s,
  .ob-system.is-demo .od-m,
  .ob-system.is-demo .od-l {
    animation: none !important;
    transform: none !important;
  }
}

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

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

export interface OrbitDotsProps {
  duration?: string;
  easing?: string;
  color?: string;
}

export default function OrbitDots({
  duration = "2s",
  easing = "linear",
  color = "#fff7e6",
}: OrbitDotsProps) {
  const style: Vars = {
    "--duration": duration,
    "--easing": easing,
    "--color": color,
  };
  return (
    <div className={styles.system} style={style} aria-hidden="true">
      <span className={styles.core} />
      <span className={`${styles.dot} ${styles.dotS}`} />
      <span className={`${styles.dot} ${styles.dotM}`} />
      <span className={`${styles.dot} ${styles.dotL}`} />
    </div>
  );
}