08Drop cap and quote styling

<main class="stage">
<div class="dq is-demo is-cap" id="dq">
  <div class="dq__bar">
    <span class="dq__badge" id="badge">float path</span>
    <div class="dq__sizes" role="group" aria-label="Drop cap line count">
      <button class="dq__size" type="button" data-lines="2" aria-pressed="false">2 lines</button>
      <button class="dq__size is-on" type="button" data-lines="3" aria-pressed="true">3 lines</button>
      <button class="dq__size" type="button" data-lines="4" aria-pressed="false">4 lines</button>
    </div>
    <button class="dq__cap" id="capBtn" type="button" aria-pressed="true">Drop cap</button>
  </div>
  <div class="dq__board">
    <article class="dq__card dq__card--short">
      <span class="dq__label">Short quote</span>
      <p class="dq__text">Good typography goes unseen.</p>
    </article>
    <article class="dq__card">
      <span class="dq__label">Long quote</span>
      <p class="dq__text">Type is made of light, not ink. The space between letters sets reading speed, the gap between lines gives the page its breath. That is why enlarging a single first letter must stay measured to the pixel.</p>
    </article>
  </div>
  <p class="dq__note">Pick the line count with chips and toggle the drop cap button</p>
</div>
</main>

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

// 드롭캡과 인용문 꾸미기 — ::first-letter 를 float 으로 띄워 첫 글자를 키우고,
// initial-letter 를 아는 브라우저에서는 @supports 안에서 그 경로로 넘어간다.
// 줄수는 --cap-lines 하나로 양쪽 경로가 같이 받는다: float 길은 calc(1.65em * 줄수),
// initial-letter 길은 initial-letter: 줄수. @property 에 숫자로 등록했으므로
// 미리보기 루프에서 2줄 → 3줄 → 4줄 로 부드럽게 자란다 (이산 컷이 아니다).
// 실측 2026-09-13: Chrome 152 는 initial-letter: var(--cap-lines) 를 그대로 계산한다.

$duration: $dur-base;
$easing: $ease-spring;
$color: $subject-ink;
$mono: ui-monospace, "Cascadia Mono", Consolas, "Courier New", monospace;
$chip-line: rgba(23, 20, 26, .30);

@property --cap-lines {
  syntax: "<number>";
  inherits: true;
  initial-value: 3;
}

@include stage($stage-paper);

.dq {
  --cap-lines: 3;
  display: flex; flex-direction: column; gap: $sp-2;
  box-sizing: border-box; width: min(100%, 440px);
}

// ── 도구 막대: 경로 배지 + 줄수 침 + 드롭캡 토글
.dq__bar { display: flex; flex-wrap: wrap; align-items: center; gap: $sp-1; }
.dq__badge {
  padding: $sp-1 $sp-2; border-radius: $r-pill;
  background: $color; color: $subject-cream;
  font-family: $mono; font-weight: 700; font-size: 10px; line-height: 1.4;
}
.dq__sizes { display: flex; gap: $sp-1; }
.dq__size, .dq__cap {
  flex: 0 0 auto; padding: $sp-1 $sp-2; border: 1px solid $chip-line; border-radius: $r-pill;
  background: transparent; color: $subject-ink; cursor: pointer;
  font-weight: 600; font-size: 11px; line-height: 1.4;
}
.dq__size.is-on, .dq__cap[aria-pressed="true"] {
  background: $color; border-color: $color; color: $subject-cream;
}
.dq__size:focus-visible, .dq__cap:focus-visible { outline: 2px solid $subject-blue; outline-offset: 2px; }

// ── 견준 판: 짧은 인용과 긴 인용 두 벌
.dq__board { display: grid; grid-template-columns: 1fr 1fr; gap: $sp-2; align-items: start; }
.dq__card {
  padding: $sp-2; border: 1px solid rgba(23, 20, 26, .12); border-radius: $r-card;
  background: $subject-cream;
}
.dq__label { display: block; margin-bottom: $sp-1; color: $subject-orange-deep; font-weight: 700; font-size: 10px; line-height: 1.4; letter-spacing: .08em; }
.dq__text { margin: 0; color: $subject-ink; font-weight: 400; font-size: 12.5px; line-height: 1.65; }

// ── 드롭캡 두 경로. 기본은 float 길(모든 브라우저), 아는 브라우저는 initial-letter 길
.dq.is-cap .dq__text::first-letter {
  float: left;
  padding-right: $sp-1; padding-top: $sp-1;
  line-height: .82;
  font-weight: 700;
  font-size: calc(1.65em * var(--cap-lines));
  color: $subject-blue-deep;
}
@supports (initial-letter: 3) {
  .dq.is-cap .dq__text::first-letter {
    initial-letter: var(--cap-lines);
    float: none;
    padding-top: 0;
  }
}

.dq__note { margin: 0; color: rgba(23, 20, 26, .78); font-weight: 500; font-size: 11px; line-height: 1.4; }

// ── 격자 미리보기 루프 (2초)
// 줄수가 2 → 3(30%) → 4(70%) 로 자랐다가 100% 에서 2 로 되돌아와 루프가 이어진다.
// 등록된 숫자 속성이라 매 프레임 보간된다 — 첫 글자와 그 주위로 다시 앉는 줄이 함께 움직인다.
.dq.is-demo {
  animation-name: dqLines; animation-duration: $dur-loop; animation-timing-function: $easing;
  animation-iteration-count: infinite;
}
@keyframes dqLines {
  0% { --cap-lines: 2; }
  30%, 40% { --cap-lines: 3; }
  70%, 80% { --cap-lines: 4; }
  100% { --cap-lines: 2; }
}

// ── 좁은 화면: 긴 인용 한 벌만 남기고 판을 한 줄로 펴 여백을 줄인다 (값을 올리지 않고 내린다)
@media (max-width: 340px) {
  .dq { gap: $sp-1; }
  .dq__board { grid-template-columns: 1fr; }
  .dq__card--short, .dq__note { display: none; }
  .dq__card { padding: $sp-1; }
  .dq__text { font-size: 11px; }
}

@media (prefers-reduced-motion: reduce) {
  .dq.is-demo {
    animation: none !important;
  }
}

@property --cap-lines {
  syntax: "<number>";
  inherits: true;
  initial-value: 3;
}
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);
}

.dq {
  --cap-lines: 3;
  display: flex;
  flex-direction: column;
  gap: 8px;
  box-sizing: border-box;
  width: min(100%, 440px);
}

.dq__bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 4px;
}

.dq__badge {
  padding: 4px 8px;
  border-radius: 999px;
  background: #17141a;
  color: #fff7e6;
  font-family: ui-monospace, "Cascadia Mono", Consolas, "Courier New", monospace;
  font-weight: 700;
  font-size: 10px;
  line-height: 1.4;
}

.dq__sizes {
  display: flex;
  gap: 4px;
}

.dq__size, .dq__cap {
  flex: 0 0 auto;
  padding: 4px 8px;
  border: 1px solid rgba(23, 20, 26, 0.3);
  border-radius: 999px;
  background: transparent;
  color: #17141a;
  cursor: pointer;
  font-weight: 600;
  font-size: 11px;
  line-height: 1.4;
}

.dq__size.is-on, .dq__cap[aria-pressed=true] {
  background: #17141a;
  border-color: #17141a;
  color: #fff7e6;
}

.dq__size:focus-visible, .dq__cap:focus-visible {
  outline: 2px solid #2f6df6;
  outline-offset: 2px;
}

.dq__board {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  align-items: start;
}

.dq__card {
  padding: 8px;
  border: 1px solid rgba(23, 20, 26, 0.12);
  border-radius: 16px;
  background: #fff7e6;
}

.dq__label {
  display: block;
  margin-bottom: 4px;
  color: #c93000;
  font-weight: 700;
  font-size: 10px;
  line-height: 1.4;
  letter-spacing: 0.08em;
}

.dq__text {
  margin: 0;
  color: #17141a;
  font-weight: 400;
  font-size: 12.5px;
  line-height: 1.65;
}

.dq.is-cap .dq__text::first-letter {
  float: left;
  padding-right: 4px;
  padding-top: 4px;
  line-height: 0.82;
  font-weight: 700;
  font-size: calc(1.65em * var(--cap-lines));
  color: #0a4fe8;
}

@supports (initial-letter: 3) {
  .dq.is-cap .dq__text::first-letter {
    initial-letter: var(--cap-lines);
    float: none;
    padding-top: 0;
  }
}
.dq__note {
  margin: 0;
  color: rgba(23, 20, 26, 0.78);
  font-weight: 500;
  font-size: 11px;
  line-height: 1.4;
}

.dq.is-demo {
  animation-name: dqLines;
  animation-duration: 2s;
  animation-timing-function: cubic-bezier(0.2, 0.8, 0.2, 1);
  animation-iteration-count: infinite;
}

@keyframes dqLines {
  0% {
    --cap-lines: 2;
  }
  30%, 40% {
    --cap-lines: 3;
  }
  70%, 80% {
    --cap-lines: 4;
  }
  100% {
    --cap-lines: 2;
  }
}
@media (max-width: 340px) {
  .dq {
    gap: 4px;
  }
  .dq__board {
    grid-template-columns: 1fr;
  }
  .dq__card--short, .dq__note {
    display: none;
  }
  .dq__card {
    padding: 4px;
  }
  .dq__text {
    font-size: 11px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .dq.is-demo {
    animation: none !important;
  }
}

var dq = document.getElementById('dq');
var capBtn = document.getElementById('capBtn');
var badge = document.getElementById('badge');

// initial-letter 를 아는 브라우저는 그 경로로 넘어간다 — 배지가 어느 쪽인지 알려 준다
if (window.CSS && CSS.supports && CSS.supports('(initial-letter: 3)')) {
  badge.textContent = 'initial-letter path';
}

capBtn.addEventListener('click', function () {
  dq.classList.remove('is-demo');
  var on = dq.classList.toggle('is-cap');
  capBtn.setAttribute('aria-pressed', on ? 'true' : 'false');
});

var sizes = document.querySelectorAll('.dq__size');
for (var i = 0; i < sizes.length; i++) {
  sizes[i].addEventListener('click', function () {
    dq.classList.remove('is-demo');
    dq.style.setProperty('--cap-lines', this.getAttribute('data-lines'));
    for (var j = 0; j < sizes.length; j++) {
      var on = sizes[j] === this;
      sizes[j].classList.toggle('is-on', on);
      sizes[j].setAttribute('aria-pressed', on ? 'true' : 'false');
    }
  });
}

// DropcapQuote — vanilla 판(run/074/demo/08-dropcap-quote/index.html) 의 React 포트.
// ::first-letter 를 float 으로 띄우고 initial-letter 를 아는 브라우저에서는 @supports 경로로 넘어간다.
// 줄수는 --cap-lines 하나로 양쪽 경로가 같이 받는다 — @property 등록 덕에 부드럽게 보간된다.
import { useEffect, useState } from "react";
import type { CSSProperties } from "react";
import styles from "./DropcapQuote.module.scss";

export type DropcapQuoteProps = {
  duration?: number;
  easing?: string;
  color?: string;
};

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

const BADGE_FALLBACK = "float 경로";
const BADGE_INITIAL = "initial-letter 경로";
const SIZES = [2, 3, 4] as const;
const SHORT_LABEL = "짧은 인용";
const LONG_LABEL = "긴 인용";
const SHORT_TEXT = "좋은 타이포그래피는 눈에 띄지 않습니다.";
const LONG_TEXT = "활자는 잉크가 아니라 빛으로 만든다. 글자 사이의 여백이 읽는 속도를 정하고, 행이 만나는 간격이 페이지의 숨을 만든다. 그래서 첫 글자 하나를 키우는 일도 자로 잰 듯 정확해야 한다.";
const NOTE = "칩으로 줄수를 고르고 드롭캡 버튼으로 켜고 끕니다";
const CAP_LABEL = "드롭캡";
const SIZES_ARIA = "드롭캡 줄수";

export default function DropcapQuote(props: DropcapQuoteProps) {
  const duration = props.duration ?? 300;
  const easing = props.easing ?? "cubic-bezier(.2, .8, .2, 1)";
  const color = props.color ?? "#17141a";
  const [preview, setPreview] = useState<boolean>(true);
  const [cap, setCap] = useState<boolean>(true);
  const [lines, setLines] = useState<number>(3);
  const [badge, setBadge] = useState<string>(BADGE_FALLBACK);

  useEffect(() => {
    // initial-letter 를 아는 브라우저는 그 경로로 넘어간다 — 배지가 어느 쪽인지 알려 준다
    if (typeof CSS !== "undefined" && CSS.supports && CSS.supports("(initial-letter: 3)")) {
      setBadge(BADGE_INITIAL);
    }
  }, []);

  const vars: Vars = {
    "--duration": duration + "ms",
    "--easing": easing,
    "--color": color,
    "--cap-lines": lines,
  };

  return (
    <main className={styles.stage}>
      <div
        className={[styles.root, preview ? " " + styles.isDemo : "", cap ? " " + styles.isCap : ""].filter(Boolean).join("")}
        style={vars}
      >
        <div className={styles.bar}>
          <span className={styles.badge}>{badge}</span>
          <div className={styles.sizes} role="group" aria-label={SIZES_ARIA}>
            {SIZES.map((n) => (
              <button
                key={n}
                className={styles.size + (lines === n ? " " + styles.ison : "")}
                type="button"
                data-lines={n}
                aria-pressed={lines === n ? "true" : "false"}
                onClick={() => { setPreview(false); setLines(n); }}
              >
                {n + "줄"}
              </button>
            ))}
          </div>
          <button
            className={styles.capBtn}
            type="button"
            aria-pressed={cap ? "true" : "false"}
            onClick={() => { setPreview(false); setCap(!cap); }}
          >
            {CAP_LABEL}
          </button>
        </div>
        <div className={styles.board}>
          <article className={styles.card + " " + styles.cardShort}>
            <span className={styles.label}>{SHORT_LABEL}</span>
            <p className={styles.text}>{SHORT_TEXT}</p>
          </article>
          <article className={styles.card}>
            <span className={styles.label}>{LONG_LABEL}</span>
            <p className={styles.text}>{LONG_TEXT}</p>
          </article>
        </div>
        <p className={styles.note}>{NOTE}</p>
      </div>
    </main>
  );
}