04Multi-line typing

<main class="stage">
  <div class="lines">
    <p class="lines__row"><span class="lines__text lines__text--1">Frontend developer</span></p>
    <p class="lines__row"><span class="lines__text lines__text--2">I love CSS animation</span></p>
    <p class="lines__row"><span class="lines__text lines__text--3">I enjoy coffee and typing</span></p>
  </div>
</main>

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

$duration: $dur-loop;                      // 세 줄이 도는 전체 루프
$easing: $ease-out;                        // 다 친 뒤 접히는 구간의 곡선 (타이핑 자체는 줄마다 steps())
$color: $subject-blue;                     // 커서 색

@include stage($stage-paper);

.lines {
  display: grid;
  gap: clamp(4px, 1.6vw, 10px);
  font-weight: 700; font-size: clamp(15px, 4.4vw, 22px); line-height: 1.5; font-family: inherit;
  color: $stage-ink;

  &__row { margin: 0; }
  &__text {
    display: inline-block;
    overflow: hidden;
    white-space: nowrap;
    vertical-align: bottom;
    width: 0;
    border-right: .1em solid $color;
    animation-duration: $duration;
    animation-timing-function: $easing;
    animation-iteration-count: infinite;

    &--1 { animation-name: l1-type; }
    &--2 { animation-name: l2-type; }
    &--3 { animation-name: l3-type; }
  }
}

@keyframes l1-type {
  0%      { width: 0; animation-timing-function: steps(9, end); }
  10%     { width: var(--full, 9ch); }
  88%     { width: var(--full, 9ch); }
  96%, 100% { width: 0; }
}
@keyframes l2-type {
  0%, 10% { width: 0; animation-timing-function: steps(16, end); }
  34%     { width: var(--full, 16ch); }
  88%     { width: var(--full, 16ch); }
  96%, 100% { width: 0; }
}
@keyframes l3-type {
  0%, 34% { width: 0; animation-timing-function: steps(13, end); }
  54%     { width: var(--full, 13ch); }
  88%     { width: var(--full, 13ch); }
  96%, 100% { width: 0; }
}

@media (prefers-reduced-motion: reduce) {
  .lines__text { animation: none; width: var(--full, 16ch); border-right-color: transparent; }
}

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);
}

.lines {
  display: grid;
  gap: clamp(4px, 1.6vw, 10px);
  font-weight: 700;
  font-size: clamp(15px, 4.4vw, 22px);
  line-height: 1.5;
  font-family: inherit;
  color: #17141a;
}
.lines__row {
  margin: 0;
}
.lines__text {
  display: inline-block;
  overflow: hidden;
  white-space: nowrap;
  vertical-align: bottom;
  width: 0;
  border-right: 0.1em solid #2f6df6;
  animation-duration: 2s;
  animation-timing-function: ease-out;
  animation-iteration-count: infinite;
}
.lines__text--1 {
  animation-name: l1-type;
}
.lines__text--2 {
  animation-name: l2-type;
}
.lines__text--3 {
  animation-name: l3-type;
}

@keyframes l1-type {
  0% {
    width: 0;
    animation-timing-function: steps(9, end);
  }
  10% {
    width: var(--full, 9ch);
  }
  88% {
    width: var(--full, 9ch);
  }
  96%, 100% {
    width: 0;
  }
}
@keyframes l2-type {
  0%, 10% {
    width: 0;
    animation-timing-function: steps(16, end);
  }
  34% {
    width: var(--full, 16ch);
  }
  88% {
    width: var(--full, 16ch);
  }
  96%, 100% {
    width: 0;
  }
}
@keyframes l3-type {
  0%, 34% {
    width: 0;
    animation-timing-function: steps(13, end);
  }
  54% {
    width: var(--full, 13ch);
  }
  88% {
    width: var(--full, 13ch);
  }
  96%, 100% {
    width: 0;
  }
}
@media (prefers-reduced-motion: reduce) {
  .lines__text {
    animation: none;
    width: var(--full, 16ch);
    border-right-color: transparent;
  }
}

(function () {
  var cv = document.createElement('canvas').getContext('2d');
  document.querySelectorAll('.lines__text').forEach(function (el) {
    cv.font = getComputedStyle(el).font;
    el.style.setProperty('--full', Math.ceil(cv.measureText(el.textContent).width) + 'px');
  });
})();

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

export type MultiLineTypingProps = {
  lines: [string, string, string];
  /** 세 줄이 도는 전체 루프 (기본 2000ms) */
  duration?: number;
  color?: string;
};

export default function MultiLineTyping({ lines, duration = 2000, color = "#2f6df6" }: MultiLineTypingProps) {
  const r1 = useRef<HTMLSpanElement | null>(null);
  const r2 = useRef<HTMLSpanElement | null>(null);
  const r3 = useRef<HTMLSpanElement | null>(null);
  useEffect(() => {
    const cv = document.createElement("canvas").getContext("2d");
    if (!cv) return;
    [r1, r2, r3].forEach((r) => {
      const el = r.current;
      if (!el) return;
      cv.font = getComputedStyle(el).font;
      el.style.setProperty("--full", Math.ceil(cv.measureText(el.textContent || "").width) + "px");
    });
  }, [lines]);
  const vars = { "--duration": `${duration}ms`, "--color": color } as CSSProperties;
  const e = (s: string) => ({ "--easing": `steps(${s.length}, end)` } as CSSProperties);
  return (
    <div className={styles.lines} style={vars}>
      <p className={styles.row}><span ref={r1} className={`${styles.text} ${styles.l1}`} style={e(lines[0])}>{lines[0]}</span></p>
      <p className={styles.row}><span ref={r2} className={`${styles.text} ${styles.l2}`} style={e(lines[1])}>{lines[1]}</span></p>
      <p className={styles.row}><span ref={r3} className={`${styles.text} ${styles.l3}`} style={e(lines[2])}>{lines[2]}</span></p>
    </div>
  );
}