03波形オシロスコープ

<svg width="0" height="0" style="position:absolute" aria-hidden="true">
  <defs>
    <symbol id="ico-waveform" viewBox="0 0 256 256" fill="currentColor"><path d="M208 96v64H48V96Z" opacity=".2"/><path d="M56 96v64a8 8 0 0 1-16 0V96a8 8 0 0 1 16 0m32-72a8 8 0 0 0-8 8v192a8 8 0 0 0 16 0V32a8 8 0 0 0-8-8m40 32a8 8 0 0 0-8 8v128a8 8 0 0 0 16 0V64a8 8 0 0 0-8-8m40 32a8 8 0 0 0-8 8v64a8 8 0 0 0 16 0V96a8 8 0 0 0-8-8m40-16a8 8 0 0 0-8 8v96a8 8 0 0 0 16 0V72a8 8 0 0 0-8-8"/></symbol>
    <symbol id="ico-play" viewBox="0 0 256 256" fill="currentColor"><path d="M228.23 134.69L84.15 222.81A8 8 0 0 1 72 216.12V39.88a8 8 0 0 1 12.15-6.69l144.08 88.12a7.82 7.82 0 0 1 0 13.38" opacity=".2"/><path d="M232.4 114.49L88.32 26.35a16 16 0 0 0-16.2-.3A15.86 15.86 0 0 0 64 39.87v176.26A15.94 15.94 0 0 0 80 232a16.07 16.07 0 0 0 8.36-2.35l144.04-88.14a15.88 15.88 0 0 0 0-27.02M80 215.94V40l143.83 88Z"/></symbol>
    <symbol id="ico-pause" viewBox="0 0 256 256" fill="currentColor"><path d="M208 48v160a8 8 0 0 1-8 8h-40a8 8 0 0 1-8-8V48a8 8 0 0 1 8-8h40a8 8 0 0 1 8 8M96 40H56a8 8 0 0 0-8 8v160a8 8 0 0 0 8 8h40a8 8 0 0 0 8-8V48a8 8 0 0 0-8-8" opacity=".2"/><path d="M200 32h-40a16 16 0 0 0-16 16v160a16 16 0 0 0 16 16h40a16 16 0 0 0 16-16V48a16 16 0 0 0-16-16m0 176h-40V48h40zM96 32H56a16 16 0 0 0-16 16v160a16 16 0 0 0 16 16h40a16 16 0 0 0 16-16V48a16 16 0 0 0-16-16m0 176H56V48h40z"/></symbol>
  </defs>
</svg>
<main class="stage">
<div class="ws is-demo" id="ws">
  <p class="ws__hint"><svg class="ws__ico" aria-hidden="true"><use href="#ico-waveform"/></svg><span>再生を押すと実際の音で動きます</span></p>
  <div class="ws__scope">
    <svg class="ws__svg" viewBox="0 0 360 96" preserveAspectRatio="none" aria-hidden="true">
      <!-- 바닥 파형: 미리 계산해 둔 정적 시퀀스. 실제 재생을 시작하면 JS 가 points 를 진짜 파형으로 매 프레임 바꾼다. -->
      <polyline class="ws__base" id="baseLine" points=""/>
      <!-- 흐르는 하이라이트: 같은 파형 위를 짧은 대시가 지나간다 — 미리보기 루프의 몸통. -->
      <polyline class="ws__flow" id="flowLine" points=""/>
    </svg>
  </div>
  <div class="ws__foot">
    <button class="ws__play" id="play" type="button" aria-pressed="false">
      <svg class="ws__ico ws__ico--play" aria-hidden="true"><use href="#ico-play"/></svg>
      <svg class="ws__ico ws__ico--pause" aria-hidden="true"><use href="#ico-pause"/></svg>
      <span id="playLabel">再生</span>
    </button>
    <p class="ws__level">
      <span class="ws__levelLabel">今の波形</span>
      <b class="ws__levelBox">
        <span class="ws__levelText" id="levelText" aria-live="polite">静か</span>
        <span class="ws__loop" aria-hidden="true"><i>静か</i><i>揺れ</i><i>大きな波</i></span>
      </b>
    </p>
  </div>
</div>
</main>

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

// 파형 오실로스코프 — 캔버스 없이 SVG polyline 하나. 색·두께·그림자는 전부 CSS 가 가진다.
// 미리보기(.is-demo)는 정적 파형 위를 stroke-dasharray 대시가 흐르는 루프 — points 는 CSS 로 움직일 수 없어서
// "같은 파형을 따라 흐르는 하이라이트"로 2초 루프를 만든다. 재생을 누르면 JS 가 points 를 진짜 파형으로 바꾼다.

$duration: $dur-quick;
$easing: $ease-out;
$color: $subject-mint;

@include stage($stage-ink);

.ws { display: flex; flex-direction: column; align-items: center; gap: $sp-3; width: 100%; max-width: 400px; }
.ws__hint {
  display: flex; align-items: center; gap: $sp-1; margin: 0;
  font-weight: 700; font-size: clamp(11px, 3vw, 12px); color: $subject-cream;
}
.ws__ico { width: 16px; height: 16px; color: $color; }

.ws__scope {
  box-sizing: border-box; width: 100%; padding: $sp-2 $sp-2 0;
  border-radius: $r-card; background: #211d26;
  border: 1px solid rgba($subject-cream, .12);
}
.ws__svg { display: block; width: 100%; height: 104px; }
.ws__base {
  fill: none; stroke: rgba($subject-cream, .28); stroke-width: 2;
  stroke-linejoin: round; stroke-linecap: round;
}
.ws__flow {
  fill: none; stroke: $color; stroke-width: 3;
  stroke-linejoin: round; stroke-linecap: round;
  filter: drop-shadow(0 0 6px rgba(76, 212, 166, .45));
}

.ws__foot { display: flex; align-items: center; justify-content: center; gap: $sp-4; width: 100%; }
.ws__play {
  display: inline-flex; align-items: center; gap: $sp-1;
  border: 0; border-radius: $r-pill; padding: $sp-2 $sp-4;
  background: $stage-yellow; color: $subject-ink; cursor: pointer;
  font-family: inherit; font-weight: 800; font-size: clamp(11px, 3vw, 12px); line-height: 1;
}
.ws__ico--pause { display: none; }
.ws__play[aria-pressed="true"] .ws__ico--play { display: none; }
.ws__play[aria-pressed="true"] .ws__ico--pause { display: inline-block; }
.ws__play .ws__ico { color: $subject-ink; }

.ws__level { margin: 0; display: flex; align-items: center; gap: $sp-2; }
.ws__levelLabel { font-weight: 700; font-size: clamp(10px, 2.6vw, 11px); color: rgba($subject-cream, .82); }
.ws__levelBox {
  position: relative; display: grid; place-items: center;
  min-width: 48px; height: 20px; border-radius: $r-xs; padding: 0 $sp-1;
  background: rgba($subject-cream, .16); color: $subject-cream;
  font-weight: 800; font-size: clamp(11px, 3vw, 12px); line-height: 1;
}
.ws__loop { position: absolute; inset: 0; display: grid; place-items: center; visibility: hidden; }
.ws__loop i { grid-area: 1 / 1; font-style: normal; visibility: hidden; }

// ── 격자 미리보기 루프 ─────────────────────────────────────────────
// 56px 대시가 파형 위를 왼쪽에서 오른쪽으로 흐른다. dashoffset 의 총 이동량 = 대시 주기(56+124=180)라
// 루프가 정확히 닫힌다. 하이라이트가 한 바퀴 도는 동안 상태 글자도 세 단계로 바뀐다(steps 컷).
.ws.is-demo .ws__flow {
  stroke-dasharray: 56 124;
  animation-name: wsFlow; animation-duration: $dur-loop; animation-timing-function: linear;
  animation-iteration-count: infinite;
}
@keyframes wsFlow {
  from { stroke-dashoffset: 180; }
  to   { stroke-dashoffset: 0; }
}
.ws.is-demo .ws__levelText { color: transparent; }
.ws.is-demo .ws__loop { visibility: visible; }
.ws.is-demo .ws__loop i {
  animation-name: wsStateName; animation-duration: $dur-loop; animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}
.ws.is-demo .ws__loop i:nth-child(1) { animation-delay: 0ms; }
.ws.is-demo .ws__loop i:nth-child(2) { animation-delay: 666ms; }
.ws.is-demo .ws__loop i:nth-child(3) { animation-delay: 1332ms; }
@keyframes wsStateName {
  0%, 33% { visibility: visible; }
  34%, 100% { visibility: hidden; }
}

@media (max-width: 340px) {
  .ws { gap: $sp-2; }
  .ws__scope { padding: $sp-1 $sp-1 0; }
  .ws__svg { height: 76px; }
  .ws__foot { gap: $sp-2; }
  .ws__play { padding: $sp-1 $sp-3; }
}

// reduce 에서는 흐르는 대시를 멈춘다 — 정적 파형이 그대로 남아 화면이 비지 않는다
@media (prefers-reduced-motion: reduce) {
  .ws.is-demo .ws__flow {
    animation: none !important;
    stroke-dasharray: none;
  }
  .ws.is-demo .ws__loop i { animation: none !important; }
  .ws.is-demo .ws__levelText { color: $subject-cream !important; }
  .ws.is-demo .ws__loop { visibility: hidden !important; }
  .ws__flow { transition: 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);
}

.ws {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  width: 100%;
  max-width: 400px;
}

.ws__hint {
  display: flex;
  align-items: center;
  gap: 4px;
  margin: 0;
  font-weight: 700;
  font-size: clamp(11px, 3vw, 12px);
  color: #fff7e6;
}

.ws__ico {
  width: 16px;
  height: 16px;
  color: #4cd4a6;
}

.ws__scope {
  box-sizing: border-box;
  width: 100%;
  padding: 8px 8px 0;
  border-radius: 16px;
  background: #211d26;
  border: 1px solid rgba(255, 247, 230, 0.12);
}

.ws__svg {
  display: block;
  width: 100%;
  height: 104px;
}

.ws__base {
  fill: none;
  stroke: rgba(255, 247, 230, 0.28);
  stroke-width: 2;
  stroke-linejoin: round;
  stroke-linecap: round;
}

.ws__flow {
  fill: none;
  stroke: #4cd4a6;
  stroke-width: 3;
  stroke-linejoin: round;
  stroke-linecap: round;
  filter: drop-shadow(0 0 6px rgba(76, 212, 166, 0.45));
}

.ws__foot {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  width: 100%;
}

.ws__play {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  border: 0;
  border-radius: 999px;
  padding: 8px 16px;
  background: #ffd23f;
  color: #17141a;
  cursor: pointer;
  font-family: inherit;
  font-weight: 800;
  font-size: clamp(11px, 3vw, 12px);
  line-height: 1;
}

.ws__ico--pause {
  display: none;
}

.ws__play[aria-pressed=true] .ws__ico--play {
  display: none;
}

.ws__play[aria-pressed=true] .ws__ico--pause {
  display: inline-block;
}

.ws__play .ws__ico {
  color: #17141a;
}

.ws__level {
  margin: 0;
  display: flex;
  align-items: center;
  gap: 8px;
}

.ws__levelLabel {
  font-weight: 700;
  font-size: clamp(10px, 2.6vw, 11px);
  color: rgba(255, 247, 230, 0.82);
}

.ws__levelBox {
  position: relative;
  display: grid;
  place-items: center;
  min-width: 48px;
  height: 20px;
  border-radius: 4px;
  padding: 0 4px;
  background: rgba(255, 247, 230, 0.16);
  color: #fff7e6;
  font-weight: 800;
  font-size: clamp(11px, 3vw, 12px);
  line-height: 1;
}

.ws__loop {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  visibility: hidden;
}

.ws__loop i {
  grid-area: 1/1;
  font-style: normal;
  visibility: hidden;
}

.ws.is-demo .ws__flow {
  stroke-dasharray: 56 124;
  animation-name: wsFlow;
  animation-duration: 2s;
  animation-timing-function: linear;
  animation-iteration-count: infinite;
}

@keyframes wsFlow {
  from {
    stroke-dashoffset: 180;
  }
  to {
    stroke-dashoffset: 0;
  }
}
.ws.is-demo .ws__levelText {
  color: transparent;
}

.ws.is-demo .ws__loop {
  visibility: visible;
}

.ws.is-demo .ws__loop i {
  animation-name: wsStateName;
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

.ws.is-demo .ws__loop i:nth-child(1) {
  animation-delay: 0ms;
}

.ws.is-demo .ws__loop i:nth-child(2) {
  animation-delay: 666ms;
}

.ws.is-demo .ws__loop i:nth-child(3) {
  animation-delay: 1332ms;
}

@keyframes wsStateName {
  0%, 33% {
    visibility: visible;
  }
  34%, 100% {
    visibility: hidden;
  }
}
@media (max-width: 340px) {
  .ws {
    gap: 8px;
  }
  .ws__scope {
    padding: 4px 4px 0;
  }
  .ws__svg {
    height: 76px;
  }
  .ws__foot {
    gap: 8px;
  }
  .ws__play {
    padding: 4px 12px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .ws.is-demo .ws__flow {
    animation: none !important;
    stroke-dasharray: none;
  }
  .ws.is-demo .ws__loop i {
    animation: none !important;
  }
  .ws.is-demo .ws__levelText {
    color: #fff7e6 !important;
  }
  .ws.is-demo .ws__loop {
    visibility: hidden !important;
  }
  .ws__flow {
    transition: none !important;
  }
}

var root = document.getElementById('ws');
var baseLine = document.getElementById('baseLine');
var flowLine = document.getElementById('flowLine');
var playBtn = document.getElementById('play');
var playLabel = document.getElementById('playLabel');
var levelText = document.getElementById('levelText');
var W = 360, H = 96, MID = H / 2, N = 60;
// 바닥 파형 — 사인 두 개를 더한 정적 시퀀스. 난수가 아니라 식이라 같은 그림이 항상 재현된다.
var pts = [];
for (var i = 0; i < N; i++) {
  var x = (i / (N - 1)) * W;
  var y = MID - Math.sin(i / N * Math.PI * 6) * 18 - Math.sin(i / N * Math.PI * 2) * 8;
  pts.push(x.toFixed(1) + ',' + y.toFixed(1));
}
baseLine.setAttribute('points', pts.join(' '));
flowLine.setAttribute('points', pts.join(' '));
var ctx = null, analyser = null, wave = null, timer = 0, playing = false;
var STATE_NAMES = ['静か', '揺れ', '大きな波'];
function buildAudio() {
  ctx = new (window.AudioContext || window.webkitAudioContext)();
  analyser = ctx.createAnalyser();
  analyser.fftSize = 2048;
  analyser.smoothingTimeConstant = 0;
  wave = new Uint8Array(analyser.fftSize);
  var out = ctx.createGain();
  out.gain.value = 0.06;
  out.connect(analyser);
  analyser.connect(ctx.destination);
  // 외부 음원 파일 없이 코드 진행을 직접 합성한다 — 네 박자마다 화음이 바뀐다.
  [196, 246.94, 293.66, 392].forEach(function (hz, n) {
    var osc = ctx.createOscillator();
    var amp = ctx.createGain();
    osc.type = n === 3 ? 'triangle' : 'sawtooth';
    osc.frequency.value = hz;
    amp.gain.value = 0;
    for (var beat = 0; beat < 64; beat++) {
      var at = ctx.currentTime + beat * 0.5;
      amp.gain.setValueAtTime(beat % 4 === n % 4 ? 0.9 : 0.25, at);
      amp.gain.exponentialRampToValueAtTime(0.02, at + 0.45);
    }
    osc.connect(amp); amp.connect(out); osc.start();
  });
}
function draw() {
  // 시간 도메인 — 주파수가 아니라 "지금 이 순간의 진폭" 을 그대로 읽는다.
  analyser.getByteTimeDomainData(wave);
  var step = Math.floor(wave.length / N);
  var line = [];
  var peak = 0;
  for (var i = 0; i < N; i++) {
    var v = (wave[i * step] - 128) / 128;
    peak = Math.max(peak, Math.abs(v));
    line.push(((i / (N - 1)) * W).toFixed(1) + ',' + (MID - v * (H / 2 - 6)).toFixed(1));
  }
  var p = line.join(' ');
  baseLine.setAttribute('points', p);
  flowLine.setAttribute('points', p);
  var st = peak < 0.18 ? 0 : peak < 0.5 ? 1 : 2;
  if (levelText.textContent !== STATE_NAMES[st]) { levelText.textContent = STATE_NAMES[st]; }
  timer = requestAnimationFrame(draw);
}
playBtn.addEventListener('click', function () {
  root.classList.remove('is-demo');
  if (!ctx) { buildAudio(); }
  playing = !playing;
  playBtn.setAttribute('aria-pressed', playing ? 'true' : 'false');
  playLabel.textContent = playing ? '停止' : '再生';
  // 자동재생 정책: AudioContext 는 사용자 제스처 뒤 resume() 해야 소리가 난다.
  if (playing) { ctx.resume(); timer = requestAnimationFrame(draw); }
  else { ctx.suspend(); cancelAnimationFrame(timer); }
});

// WaveformScope — vanilla 판(run/291/demo/03-audio-viz-waveform-scope/index.html) 의 React 포트.
// 시간 도메인 파형을 SVG polyline 의 points 에 그대로 쓴다. 캔버스 없이 선 하나.
import { useEffect, useRef, useState } from "react";
import type { CSSProperties } from "react";
import styles from "./WaveformScope.module.scss";

export type WaveformScopeProps = {
  /** 격자 미리보기용 2초 자동 루프. 재생을 누르면 꺼진다 */
  demo?: boolean;
  duration?: number;
  easing?: string;
  color?: string;
};

type Vars = CSSProperties & { "--duration"?: string; "--easing"?: string; "--color"?: string };
/** ambient 타입에 useRef<T> 의 null 합집합이 없어 로컬로 좁힌다 */
type Box<T> = { current: T };

const W = 360;
const H = 96;
const MID = H / 2;
const N = 60;
const STATE_NAMES = ["고요", "출렁", "큰물결"];

/** 바닥 파형 — 사인 두 개를 더한 정적 시퀀스. 난수가 아니라 식이라 같은 그림이 항상 재현된다. */
const BASE_PTS: string[] = [];
for (let i = 0; i < N; i++) {
  const x = (i / (N - 1)) * W;
  const y = MID - Math.sin((i / N) * Math.PI * 6) * 18 - Math.sin((i / N) * Math.PI * 2) * 8;
  BASE_PTS.push(x.toFixed(1) + "," + y.toFixed(1));
}
const BASE_LINE = BASE_PTS.join(" ");

export default function WaveformScope({
  demo = true,
  duration = 220,
  easing = "ease-out",
  color = "#4cd4a6",
}: WaveformScopeProps) {
  const [live, setLive] = useState(demo);
  const [playing, setPlaying] = useState(false);
  const [line, setLine] = useState(BASE_LINE);
  const [state, setState] = useState(STATE_NAMES[0]);
  const ctxBox = useRef(null) as Box<AudioContext | null>;
  const nodeBox = useRef(null) as Box<AnalyserNode | null>;
  const frameBox = useRef(0) as Box<number>;
  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };

  useEffect(() => {
    return () => {
      cancelAnimationFrame(frameBox.current);
      if (ctxBox.current) {
        ctxBox.current.close();
      }
    };
  }, []);

  function buildAudio() {
    const ctx = new AudioContext();
    const analyser = ctx.createAnalyser();
    analyser.fftSize = 2048;
    analyser.smoothingTimeConstant = 0;
    const out = ctx.createGain();
    out.gain.value = 0.06;
    out.connect(analyser);
    analyser.connect(ctx.destination);
    // 외부 음원 파일 없이 코드 진행을 직접 합성한다 — 네 박자마다 화음이 바뀐다.
    [196, 246.94, 293.66, 392].forEach((hz, n) => {
      const osc = ctx.createOscillator();
      const amp = ctx.createGain();
      osc.type = n === 3 ? "triangle" : "sawtooth";
      osc.frequency.value = hz;
      amp.gain.value = 0;
      for (let beat = 0; beat < 64; beat++) {
        const at = ctx.currentTime + beat * 0.5;
        amp.gain.setValueAtTime(beat % 4 === n % 4 ? 0.9 : 0.25, at);
        amp.gain.exponentialRampToValueAtTime(0.02, at + 0.45);
      }
      osc.connect(amp);
      amp.connect(out);
      osc.start();
    });
    ctxBox.current = ctx;
    nodeBox.current = analyser;
  }

  function draw() {
    const analyser = nodeBox.current;
    if (!analyser) {
      return;
    }
    // 시간 도메인 — 주파수가 아니라 "지금 이 순간의 진폭" 을 그대로 읽는다.
    const wave = new Uint8Array(analyser.fftSize);
    analyser.getByteTimeDomainData(wave);
    const step = Math.floor(wave.length / N);
    const next: string[] = [];
    let peak = 0;
    for (let i = 0; i < N; i++) {
      const v = (wave[i * step] - 128) / 128;
      peak = Math.max(peak, Math.abs(v));
      next.push(((i / (N - 1)) * W).toFixed(1) + "," + (MID - v * (H / 2 - 6)).toFixed(1));
    }
    setLine(next.join(" "));
    setState(STATE_NAMES[peak < 0.18 ? 0 : peak < 0.5 ? 1 : 2]);
    frameBox.current = requestAnimationFrame(draw);
  }

  function toggle() {
    setLive(false);
    if (!ctxBox.current) {
      buildAudio();
    }
    const ctx = ctxBox.current;
    if (!ctx) {
      return;
    }
    const next = !playing;
    setPlaying(next);
    // 자동재생 정책: AudioContext 는 사용자 제스처 뒤 resume() 해야 소리가 난다.
    if (next) {
      ctx.resume();
      frameBox.current = requestAnimationFrame(draw);
    } else {
      ctx.suspend();
      cancelAnimationFrame(frameBox.current);
    }
  }

  const cls = [styles.root, live ? styles.isDemo : ""].filter(Boolean).join(" ");
  return (
    <main className={styles.stage} style={vars}>
      <svg width="0" height="0" style={{ position: "absolute" }} aria-hidden="true">
        <defs>
          <symbol id="ico-waveform" viewBox="0 0 256 256" fill="currentColor">
            <path d="M208 96v64H48V96Z" opacity=".2" />
            <path d="M56 96v64a8 8 0 0 1-16 0V96a8 8 0 0 1 16 0m32-72a8 8 0 0 0-8 8v192a8 8 0 0 0 16 0V32a8 8 0 0 0-8-8m40 32a8 8 0 0 0-8 8v128a8 8 0 0 0 16 0V64a8 8 0 0 0-8-8m40 32a8 8 0 0 0-8 8v64a8 8 0 0 0 16 0V96a8 8 0 0 0-8-8m40-16a8 8 0 0 0-8 8v96a8 8 0 0 0 16 0V72a8 8 0 0 0-8-8" />
          </symbol>
          <symbol id="ico-play" viewBox="0 0 256 256" fill="currentColor">
            <path d="M228.23 134.69L84.15 222.81A8 8 0 0 1 72 216.12V39.88a8 8 0 0 1 12.15-6.69l144.08 88.12a7.82 7.82 0 0 1 0 13.38" opacity=".2" />
            <path d="M232.4 114.49L88.32 26.35a16 16 0 0 0-16.2-.3A15.86 15.86 0 0 0 64 39.87v176.26A15.94 15.94 0 0 0 80 232a16.07 16.07 0 0 0 8.36-2.35l144.04-88.14a15.88 15.88 0 0 0 0-27.02M80 215.94V40l143.83 88Z" />
          </symbol>
          <symbol id="ico-pause" viewBox="0 0 256 256" fill="currentColor">
            <path d="M208 48v160a8 8 0 0 1-8 8h-40a8 8 0 0 1-8-8V48a8 8 0 0 1 8-8h40a8 8 0 0 1 8 8M96 40H56a8 8 0 0 0-8 8v160a8 8 0 0 0 8 8h40a8 8 0 0 0 8-8V48a8 8 0 0 0-8-8" opacity=".2" />
            <path d="M200 32h-40a16 16 0 0 0-16 16v160a16 16 0 0 0 16 16h40a16 16 0 0 0 16-16V48a16 16 0 0 0-16-16m0 176h-40V48h40zM96 32H56a16 16 0 0 0-16 16v160a16 16 0 0 0 16 16h40a16 16 0 0 0 16-16V48a16 16 0 0 0-16-16m0 176H56V48h40z" />
          </symbol>
        </defs>
      </svg>
      <div className={cls}>
        <p className={styles.hint}>
          <svg className={styles.ico} aria-hidden="true">
            <use href="#ico-waveform" />
          </svg>
          <span>재생을 누르면 실제 소리로 움직입니다</span>
        </p>
        <div className={styles.scope}>
          <svg className={styles.svg} viewBox="0 0 360 96" preserveAspectRatio="none" aria-hidden="true">
            <polyline className={styles.base} points={line} />
            <polyline className={styles.flow} points={line} />
          </svg>
        </div>
        <div className={styles.foot}>
          <button className={styles.play} type="button" aria-pressed={playing} onClick={toggle}>
            <svg className={[styles.ico, playing ? styles.icoHidden : ""].join(" ")} aria-hidden="true">
              <use href="#ico-play" />
            </svg>
            <svg className={[styles.ico, playing ? "" : styles.icoHidden].join(" ")} aria-hidden="true">
              <use href="#ico-pause" />
            </svg>
            <span>{playing ? "정지" : "재생"}</span>
          </button>
          <p className={styles.level}>
            <span className={styles.levelLabel}>지금 파형</span>
            <b className={styles.levelBox}>
              <span className={styles.levelText} aria-live="polite">
                {state}
              </span>
              <span className={styles.loop} aria-hidden="true">
                <i>고요</i>
                <i>출렁</i>
                <i>큰물결</i>
              </span>
            </b>
          </p>
        </div>
      </div>
    </main>
  );
}