03ファイルが落ちる破線ドロップゾーン

<main class="stage">
  <section class="dz is-demo">
    <div class="dz__zone" id="dz-zone" role="button" tabindex="0" aria-describedby="dz-msg">
      <span class="dz__file" aria-hidden="true"><svg viewBox="0 0 256 256" width="1em" height="1em"><g fill="currentColor"><path d="M208 88h-56V32Z" opacity=".2"/><path d="m213.66 82.34l-56-56A8 8 0 0 0 152 24H56a16 16 0 0 0-16 16v176a16 16 0 0 0 16 16h144a16 16 0 0 0 16-16V88a8 8 0 0 0-2.34-5.66M160 51.31L188.69 80H160ZM200 216H56V40h88v48a8 8 0 0 0 8 8h48zm-32-80a8 8 0 0 1-8 8H96a8 8 0 0 1 0-16h64a8 8 0 0 1 8 8m0 32a8 8 0 0 1-8 8H96a8 8 0 0 1 0-16h64a8 8 0 0 1 8 8"/></g></svg></span>
      <span class="dz__cloud" aria-hidden="true"><svg viewBox="0 0 256 256" width="1em" height="1em"><g fill="currentColor"><path d="M240 128a80 80 0 0 1-80 80H72A56 56 0 1 1 85.92 97.74v.1A80 80 0 0 1 240 128" opacity=".2"/><path d="M178.34 165.66L160 147.31V208a8 8 0 0 1-16 0v-60.69l-18.34 18.35a8 8 0 0 1-11.32-11.32l32-32a8 8 0 0 1 11.32 0l32 32a8 8 0 0 1-11.32 11.32M160 40a88.08 88.08 0 0 0-78.71 48.68A64 64 0 1 0 72 216h40a8 8 0 0 0 0-16H72a48 48 0 0 1 0-96c1.1 0 2.2 0 3.29.12A88 88 0 0 0 72 128a8 8 0 0 0 16 0a72 72 0 1 1 100.8 66a8 8 0 0 0 3.2 15.34a7.9 7.9 0 0 0 3.2-.68A88 88 0 0 0 160 40"/></g></svg></span>
    </div>
    <p class="dz__msg" id="dz-msg" data-got="{f} を受け取りました" aria-live="polite">ファイルをドロップするか、クリックして選んでください</p>
    <input class="dz__input" id="dz-input" type="file" hidden>
  </section>
</main>

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

$duration: $dur-loop;
$easing: $ease-spring;
$color: $subject-cream;

@include stage($stage-orange);

.dz {
  box-sizing: border-box;
  width: min(248px, 86vw);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: $sp-2;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  color: $subject-ink;   // AA 4.5: cream on orange 3.11 -> ink 5.50
}

.dz__zone {
  position: relative;
  box-sizing: border-box;
  width: 100%;
  height: 104px;
  padding-bottom: $sp-3;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  border: 2px dashed rgba(255, 247, 230, .52);
  border-radius: $r-card;
  background: rgba(255, 247, 230, .08);
  cursor: pointer;
  overflow: hidden;
  transition: border-color $dur-quick $ease-out, background $dur-quick $ease-out;
}
.dz__zone:hover,
.dz__zone.is-over { border-color: $color; background: rgba(255, 247, 230, .18); }
.dz__zone:focus-visible { outline: 2px solid $color; outline-offset: 2px; }

.dz__cloud {
  display: block;
  font-size: 36px;
  line-height: 0;
  color: rgba(23, 20, 26, .78);
}
.dz__file {
  position: absolute;
  left: 50%;
  top: $sp-2;
  margin-left: -12px;
  font-size: 24px;
  line-height: 0;
  color: $subject-ink;   // AA 4.5: cream on orange 3.11 -> ink 5.50
  opacity: 0;
}

.dz__msg {
  margin: 0;
  font-size: 11px;
  line-height: 14px;
  font-weight: 700;
  text-align: center;
}

// ── 자동 루프: 파일이 떨어져 닿으면 steps(1,end) 로 한 프레임에 사라진다 (반투명 겹침 없음) ──
.dz.is-demo .dz__file { animation: dz-fall $duration $easing infinite; }
@keyframes dz-fall {
  0%   { transform: translateY(-28px) scale(.82); opacity: 0; }
  16%  { transform: translateY(-28px) scale(.82); opacity: 1; }
  62%  { transform: translateY(30px) scale(1); opacity: 1; }
  70%  { transform: translateY(26px) scale(1); opacity: 1; }
  70.1%, 100% { transform: translateY(-28px) scale(.82); opacity: 0; }
}
.dz.is-demo .dz__cloud { animation: dz-lift $duration $easing infinite; }
@keyframes dz-lift {
  0%, 100% { transform: scale(1); opacity: .78; }
  62%      { transform: scale(1.1); opacity: 1; }
}

@media (prefers-reduced-motion: reduce) {
  .dz.is-demo .dz__file,
  .dz.is-demo .dz__cloud { animation: none !important; }
  .dz__zone { 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);
}

.dz {
  box-sizing: border-box;
  width: min(248px, 86vw);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  color: #17141a;
}

.dz__zone {
  position: relative;
  box-sizing: border-box;
  width: 100%;
  height: 104px;
  padding-bottom: 12px;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  border: 2px dashed rgba(255, 247, 230, 0.52);
  border-radius: 16px;
  background: rgba(255, 247, 230, 0.08);
  cursor: pointer;
  overflow: hidden;
  transition: border-color 220ms ease-out, background 220ms ease-out;
}

.dz__zone:hover,
.dz__zone.is-over {
  border-color: #fff7e6;
  background: rgba(255, 247, 230, 0.18);
}

.dz__zone:focus-visible {
  outline: 2px solid #fff7e6;
  outline-offset: 2px;
}

.dz__cloud {
  display: block;
  font-size: 36px;
  line-height: 0;
  color: rgba(23, 20, 26, 0.78);
}

.dz__file {
  position: absolute;
  left: 50%;
  top: 8px;
  margin-left: -12px;
  font-size: 24px;
  line-height: 0;
  color: #17141a;
  opacity: 0;
}

.dz__msg {
  margin: 0;
  font-size: 11px;
  line-height: 14px;
  font-weight: 700;
  text-align: center;
}

.dz.is-demo .dz__file {
  animation: dz-fall 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

@keyframes dz-fall {
  0% {
    transform: translateY(-28px) scale(0.82);
    opacity: 0;
  }
  16% {
    transform: translateY(-28px) scale(0.82);
    opacity: 1;
  }
  62% {
    transform: translateY(30px) scale(1);
    opacity: 1;
  }
  70% {
    transform: translateY(26px) scale(1);
    opacity: 1;
  }
  70.1%, 100% {
    transform: translateY(-28px) scale(0.82);
    opacity: 0;
  }
}
.dz.is-demo .dz__cloud {
  animation: dz-lift 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

@keyframes dz-lift {
  0%, 100% {
    transform: scale(1);
    opacity: 0.78;
  }
  62% {
    transform: scale(1.1);
    opacity: 1;
  }
}
@media (prefers-reduced-motion: reduce) {
  .dz.is-demo .dz__file,
  .dz.is-demo .dz__cloud {
    animation: none !important;
  }
  .dz__zone {
    transition: none;
  }
}

// 실제 동작: 끌어다 놓기와 누르기 둘 다 받는다. 파일이 들어오면 이름이 안내 줄을 대신한다.
var card = document.querySelector('.dz');
var zone = document.getElementById('dz-zone');
var input = document.getElementById('dz-input');
var msg = document.getElementById('dz-msg');
var IDLE = msg.textContent;
function took(name) {
  card.classList.remove('is-demo');
  zone.classList.remove('is-over');
  msg.textContent = name ? msg.dataset.got.replace('{f}', name) : IDLE;
}
zone.addEventListener('click', function () { input.click(); });
zone.addEventListener('keydown', function (e) {
  if (e.key === 'Enter' || e.key === ' ') { input.click(); e.preventDefault(); }
});
zone.addEventListener('dragover', function (e) { e.preventDefault(); zone.classList.add('is-over'); });
zone.addEventListener('dragleave', function () { zone.classList.remove('is-over'); });
zone.addEventListener('drop', function (e) {
  e.preventDefault();
  took(e.dataTransfer && e.dataTransfer.files[0] ? e.dataTransfer.files[0].name : '');
});
input.addEventListener('change', function () { took(input.files[0] ? input.files[0].name : ''); });

import { useRef, useState } from "react";
import type { CSSProperties } from "react";
import styles from "./DropzoneCard.module.scss";

export type DropzoneCardProps = {
  idle?: string;
  got?: string;
  duration?: number;
  easing?: string;
  color?: string;
};

type Vars = CSSProperties & { "--duration"?: string; "--easing"?: string; "--color"?: string };
type KeyEvt = { key: string; preventDefault: () => void };
type DropEvt = { preventDefault: () => void; dataTransfer: { files: { name: string }[] } | null };
type FileEvt = { target: { files: { name: string }[] | null } };

export default function DropzoneCard({
  idle = "Drop a file here, or click to choose one",
  got = "Got {f}",
  duration = 2000,
  easing = "cubic-bezier(.2,.8,.2,1)",
  color = "#fff7e6",
}: DropzoneCardProps) {
  const [msg, setMsg] = useState(idle);
  const [over, setOver] = useState(false);
  const [loop, setLoop] = useState(true);
  const inputRef = useRef<HTMLInputElement>(null);
  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };

  function took(name: string) {
    setLoop(false);
    setOver(false);
    setMsg(name ? got.replace("{f}", name) : idle);
  }

  return (
    <section className={`${styles.dz} ${loop ? styles.isDemo : ""}`} style={vars}>
      <div
        className={`${styles.zone} ${over ? styles.isOver : ""}`}
        role="button"
        tabIndex={0}
        onClick={() => inputRef.current?.click()}
        onKeyDown={(e: KeyEvt) => {
          if (e.key === "Enter" || e.key === " ") { inputRef.current?.click(); e.preventDefault(); }
        }}
        onDragOver={(e: DropEvt) => { e.preventDefault(); setOver(true); }}
        onDragLeave={() => setOver(false)}
        onDrop={(e: DropEvt) => {
          e.preventDefault();
          took(e.dataTransfer && e.dataTransfer.files[0] ? e.dataTransfer.files[0].name : "");
        }}
      >
        <span className={styles.file} aria-hidden="true">
          <svg viewBox="0 0 256 256" width="1em" height="1em">
            <g fill="currentColor">
              <path d="M208 88h-56V32Z" opacity=".2" />
              <path d="m213.66 82.34l-56-56A8 8 0 0 0 152 24H56a16 16 0 0 0-16 16v176a16 16 0 0 0 16 16h144a16 16 0 0 0 16-16V88a8 8 0 0 0-2.34-5.66M160 51.31L188.69 80H160ZM200 216H56V40h88v48a8 8 0 0 0 8 8h48zm-32-80a8 8 0 0 1-8 8H96a8 8 0 0 1 0-16h64a8 8 0 0 1 8 8m0 32a8 8 0 0 1-8 8H96a8 8 0 0 1 0-16h64a8 8 0 0 1 8 8" />
            </g>
          </svg>
        </span>
        <span className={styles.cloud} aria-hidden="true">
          <svg viewBox="0 0 256 256" width="1em" height="1em">
            <g fill="currentColor">
              <path d="M240 128a80 80 0 0 1-80 80H72A56 56 0 1 1 85.92 97.74v.1A80 80 0 0 1 240 128" opacity=".2" />
              <path d="M178.34 165.66L160 147.31V208a8 8 0 0 1-16 0v-60.69l-18.34 18.35a8 8 0 0 1-11.32-11.32l32-32a8 8 0 0 1 11.32 0l32 32a8 8 0 0 1-11.32 11.32M160 40a88.08 88.08 0 0 0-78.71 48.68A64 64 0 1 0 72 216h40a8 8 0 0 0 0-16H72a48 48 0 0 1 0-96c1.1 0 2.2 0 3.29.12A88 88 0 0 0 72 128a8 8 0 0 0 16 0a72 72 0 1 1 100.8 66a8 8 0 0 0 3.2 15.34a7.9 7.9 0 0 0 3.2-.68A88 88 0 0 0 160 40" />
            </g>
          </svg>
        </span>
      </div>
      <p className={styles.msg} aria-live="polite">{msg}</p>
      <input
        className={styles.input}
        ref={inputRef}
        type="file"
        hidden
        onChange={(e: FileEvt) => took(e.target.files && e.target.files[0] ? e.target.files[0].name : "")}
      />
    </section>
  );
}