08足元に張り付いて計算し直す合計行

<main class="stage">
  <div class="sm is-demo" id="sm">
    <div class="sm__head" role="row">
      <span role="columnheader">期間</span><span role="columnheader">金額</span>
    </div>
    <div class="sm__view" id="sm-view" role="grid" aria-label="精算リスト" tabindex="0">
      <div class="sm__track" id="sm-track" role="rowgroup">
        <button class="sm__row" type="button" role="row" data-v="42"><span role="gridcell">3月 1週</span><span role="gridcell">42</span></button>
        <button class="sm__row" type="button" role="row" data-v="38"><span role="gridcell">3月 2週</span><span role="gridcell">38</span></button>
        <button class="sm__row" type="button" role="row" data-v="51"><span role="gridcell">3月 3週</span><span role="gridcell">51</span></button>
        <button class="sm__row" type="button" role="row" data-v="27"><span role="gridcell">3月 4週</span><span role="gridcell">27</span></button>
        <button class="sm__row" type="button" role="row" data-v="60"><span role="gridcell">4月 1週</span><span role="gridcell">60</span></button>
      </div>
      <div class="sm__sum" id="sm-sum" role="row">
        <span class="sm__sic" aria-hidden="true"><svg viewBox="0 0 256 256" width="1em" height="1em" fill="currentColor"><g><path d="M192 48v160H64l64-80l-64-80Z" opacity=".2"/><path d="M184 72V56H80.65l53.6 67a8 8 0 0 1 0 10l-53.6 67H184v-16a8 8 0 0 1 16 0v24a8 8 0 0 1-8 8H64a8 8 0 0 1-6.25-13l60-75l-60-75A8 8 0 0 1 64 40h128a8 8 0 0 1 8 8v24a8 8 0 0 1-16 0"/></g></svg></span>
        <span class="sm__label" role="gridcell">合計</span>
        <span class="sm__v" role="gridcell"><b class="sm__all" id="sm-all">218</b><b class="sm__sel">38</b></span>
      </div>
    </div>
  </div>
</main>

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

$duration: $dur-quick;
$easing: $ease-spring;
$color: $subject-blue;

@include stage($stage-paper);

$row-h: 26px;
$ink: $subject-ink;
$line: color.mix($ink, $stage-paper, 12%);

.sm {
  box-sizing: border-box;
  width: min(276px, 92vw);
  border: 2px solid $ink;
  border-radius: $r-card;
  background: $stage-paper;
  overflow: hidden;
  color: $ink;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
}

.sm__head {
  display: grid;
  grid-template-columns: 1fr 72px;
  height: 24px;
  border-bottom: 2px solid $ink;
  background: color.mix($ink, $stage-paper, 8%);
}
.sm__head > * {
  padding: 0 $sp-2;
  font-size: 11px;
  line-height: 24px;
  font-weight: 700;
}
.sm__head > :last-child { text-align: right; }

// ── 스크롤 상자 — 여기에는 transform 을 걸지 않는다 ────
.sm__view {
  position: relative;
  height: 78px;
  overflow-y: auto;
  overscroll-behavior: contain;
}
.sm__view:focus-visible { outline: 2px solid $color; outline-offset: -2px; }

.sm__track { display: block; }
.sm__row {
  display: grid;
  grid-template-columns: 1fr 72px;
  width: 100%;
  height: $row-h;
  padding: 0;
  border: 0;
  box-shadow: inset 0 -1px 0 $line;
  background: $stage-paper;
  color: $ink;
  font-family: inherit;
  text-align: left;
  cursor: pointer;
}
.sm__row > * {
  padding: 0 $sp-2;
  font-size: 12px;
  line-height: $row-h;
  font-weight: 500;
}
.sm__row > :last-child { text-align: right; font-weight: 700; }
.sm__row.is-pick { background: rgba(47, 109, 246, .14); }
.sm__row:focus-visible { outline: 2px solid $color; outline-offset: -2px; }

// ── 바닥에 붙는 합계 줄 ───────────────────────────────
.sm__sum {
  position: sticky;
  bottom: 0;
  z-index: 2;
  display: grid;
  grid-template-columns: 16px 1fr 72px;
  align-items: center;
  height: 24px;
  border-top: 2px solid $ink;
  background: $stage-yellow;
  box-shadow: none;
}
.sm.is-more .sm__sum { box-shadow: 0 -6px 10px rgba(23, 20, 26, .22); }
.sm__sic { display: inline-flex; width: 12px; height: 12px; margin-left: $sp-1; }
.sm__label {
  padding: 0 $sp-1;
  font-size: 11px;
  line-height: 24px;
  font-weight: 700;
}
.sm__v {
  position: relative;
  padding: 0 $sp-2;
  font-size: 12px;
  line-height: 24px;
  text-align: right;
}
.sm__all, .sm__sel { font-weight: 800; }
.sm__sel { position: absolute; right: 8px; top: 0; color: $color; opacity: 0; }
.sm__sum.is-part .sm__label { color: $color; }

// ── 자동 루프 (2s) ───────────────────────────────────
// 스크롤 상자(.sm__view) 자체가 아니라 안쪽 줄묶음(.sm__track)만 옮긴다 — 상자에 transform 을
// 걸면 100% 가 상자 자기 폭 기준이라 내용이 통째로 날아간다(051 실측과 같은 계열).
// 10~44% 내려가고 44% 에 끝에 닿아 그림자를 끈다. 56% 에 한 줄을 골라 합계가 부분합으로 컷 교체.
.sm.is-demo .sm__track {
  animation-name: sm-scroll;
  animation-duration: $dur-loop;
  animation-timing-function: $easing;
  animation-iteration-count: infinite;
}
.sm.is-demo .sm__sum {
  animation-name: sm-shade;
  animation-duration: $dur-loop;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}
.sm.is-demo .sm__row:nth-child(2) {
  animation-name: sm-pick;
  animation-duration: $dur-loop;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}
.sm.is-demo .sm__all {
  animation-name: sm-off;
  animation-duration: $dur-loop;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}
.sm.is-demo .sm__sel {
  animation-name: sm-on;
  animation-duration: $dur-loop;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

@keyframes sm-scroll {
  0%   { transform: translateY(0); }
  10%  { transform: translateY(0); }
  44%  { transform: translateY(-52px); }
  70%  { transform: translateY(-52px); }
  86%  { transform: translateY(0); }
  100% { transform: translateY(0); }
}
@keyframes sm-shade {
  0%   { box-shadow: 0 -6px 10px rgba(23, 20, 26, .22); }
  44%  { box-shadow: none; }
  78%  { box-shadow: 0 -6px 10px rgba(23, 20, 26, .22); }
  100% { box-shadow: 0 -6px 10px rgba(23, 20, 26, .22); }
}
@keyframes sm-pick {
  0%   { background: $stage-paper; }
  56%  { background: rgba(47, 109, 246, .14); }
  76%  { background: $stage-paper; }
  100% { background: $stage-paper; }
}
@keyframes sm-off {
  0%   { opacity: 1; }
  56%  { opacity: 0; }
  76%  { opacity: 1; }
  100% { opacity: 1; }
}
@keyframes sm-on {
  0%   { opacity: 0; }
  56%  { opacity: 1; }
  76%  { opacity: 0; }
  100% { opacity: 0; }
}

// 320×200 — 금액 열과 셀 여백만 줄인다. 스크롤 상자 높이는 그대로 둔다
@media (max-width: 340px) {
  .sm__head, .sm__row { grid-template-columns: 1fr 60px; }
  .sm__sum { grid-template-columns: 16px 1fr 60px; }
  .sm__head > *, .sm__row > * { padding: 0 $sp-1; }
}

@media (prefers-reduced-motion: reduce) {
  .sm.is-demo .sm__track,
  .sm.is-demo .sm__sum,
  .sm.is-demo .sm__row:nth-child(2),
  .sm.is-demo .sm__all,
  .sm.is-demo .sm__sel { animation: none !important; }
  .sm.is-demo .sm__sum { box-shadow: 0 -6px 10px rgba(23, 20, 26, .22); }
}

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);
}

.sm {
  box-sizing: border-box;
  width: min(276px, 92vw);
  border: 2px solid #17141a;
  border-radius: 16px;
  background: #ffffff;
  overflow: hidden;
  color: #17141a;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
}

.sm__head {
  display: grid;
  grid-template-columns: 1fr 72px;
  height: 24px;
  border-bottom: 2px solid #17141a;
  background: rgb(92.7215686275%, 92.6274509804%, 92.8156862745%);
}

.sm__head > * {
  padding: 0 8px;
  font-size: 11px;
  line-height: 24px;
  font-weight: 700;
}

.sm__head > :last-child {
  text-align: right;
}

.sm__view {
  position: relative;
  height: 78px;
  overflow-y: auto;
  overscroll-behavior: contain;
}

.sm__view:focus-visible {
  outline: 2px solid #2f6df6;
  outline-offset: -2px;
}

.sm__track {
  display: block;
}

.sm__row {
  display: grid;
  grid-template-columns: 1fr 72px;
  width: 100%;
  height: 26px;
  padding: 0;
  border: 0;
  box-shadow: inset 0 -1px 0 rgb(89.0823529412%, 88.9411764706%, 89.2235294118%);
  background: #ffffff;
  color: #17141a;
  font-family: inherit;
  text-align: left;
  cursor: pointer;
}

.sm__row > * {
  padding: 0 8px;
  font-size: 12px;
  line-height: 26px;
  font-weight: 500;
}

.sm__row > :last-child {
  text-align: right;
  font-weight: 700;
}

.sm__row.is-pick {
  background: rgba(47, 109, 246, 0.14);
}

.sm__row:focus-visible {
  outline: 2px solid #2f6df6;
  outline-offset: -2px;
}

.sm__sum {
  position: sticky;
  bottom: 0;
  z-index: 2;
  display: grid;
  grid-template-columns: 16px 1fr 72px;
  align-items: center;
  height: 24px;
  border-top: 2px solid #17141a;
  background: #ffd23f;
  box-shadow: none;
}

.sm.is-more .sm__sum {
  box-shadow: 0 -6px 10px rgba(23, 20, 26, 0.22);
}

.sm__sic {
  display: inline-flex;
  width: 12px;
  height: 12px;
  margin-left: 4px;
}

.sm__label {
  padding: 0 4px;
  font-size: 11px;
  line-height: 24px;
  font-weight: 700;
}

.sm__v {
  position: relative;
  padding: 0 8px;
  font-size: 12px;
  line-height: 24px;
  text-align: right;
}

.sm__all, .sm__sel {
  font-weight: 800;
}

.sm__sel {
  position: absolute;
  right: 8px;
  top: 0;
  color: #2f6df6;
  opacity: 0;
}

.sm__sum.is-part .sm__label {
  color: #2f6df6;
}

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

.sm.is-demo .sm__sum {
  animation-name: sm-shade;
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

.sm.is-demo .sm__row:nth-child(2) {
  animation-name: sm-pick;
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

.sm.is-demo .sm__all {
  animation-name: sm-off;
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

.sm.is-demo .sm__sel {
  animation-name: sm-on;
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

@keyframes sm-scroll {
  0% {
    transform: translateY(0);
  }
  10% {
    transform: translateY(0);
  }
  44% {
    transform: translateY(-52px);
  }
  70% {
    transform: translateY(-52px);
  }
  86% {
    transform: translateY(0);
  }
  100% {
    transform: translateY(0);
  }
}
@keyframes sm-shade {
  0% {
    box-shadow: 0 -6px 10px rgba(23, 20, 26, 0.22);
  }
  44% {
    box-shadow: none;
  }
  78% {
    box-shadow: 0 -6px 10px rgba(23, 20, 26, 0.22);
  }
  100% {
    box-shadow: 0 -6px 10px rgba(23, 20, 26, 0.22);
  }
}
@keyframes sm-pick {
  0% {
    background: #ffffff;
  }
  56% {
    background: rgba(47, 109, 246, 0.14);
  }
  76% {
    background: #ffffff;
  }
  100% {
    background: #ffffff;
  }
}
@keyframes sm-off {
  0% {
    opacity: 1;
  }
  56% {
    opacity: 0;
  }
  76% {
    opacity: 1;
  }
  100% {
    opacity: 1;
  }
}
@keyframes sm-on {
  0% {
    opacity: 0;
  }
  56% {
    opacity: 1;
  }
  76% {
    opacity: 0;
  }
  100% {
    opacity: 0;
  }
}
@media (max-width: 340px) {
  .sm__head, .sm__row {
    grid-template-columns: 1fr 60px;
  }
  .sm__sum {
    grid-template-columns: 16px 1fr 60px;
  }
  .sm__head > *, .sm__row > * {
    padding: 0 4px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .sm.is-demo .sm__track,
  .sm.is-demo .sm__sum,
  .sm.is-demo .sm__row:nth-child(2),
  .sm.is-demo .sm__all,
  .sm.is-demo .sm__sel {
    animation: none !important;
  }
  .sm.is-demo .sm__sum {
    box-shadow: 0 -6px 10px rgba(23, 20, 26, 0.22);
  }
}

// 실제 동작: 合計 줄은 스크롤 상자 안에서 bottom:0 에 붙어 있고, 끝까지 내려가면 그림자를 끈다.
var sm = document.getElementById('sm');
var smView = document.getElementById('sm-view');
var smAll = document.getElementById('sm-all');
function smRows() { return [].slice.call(document.querySelectorAll('.sm__row')); }
function smSum() {
  var picked = smRows().filter(function (r) { return r.classList.contains('is-pick'); });
  var list = picked.length ? picked : smRows();
  smAll.textContent = String(list.reduce(function (n, r) { return n + (+r.dataset.v); }, 0));
  document.getElementById('sm-sum').classList.toggle('is-part', picked.length > 0);
}
function smShade() {
  var left = smView.scrollHeight - smView.scrollTop - smView.clientHeight;
  sm.classList.toggle('is-more', left > 2);
}
smView.addEventListener('scroll', function () { sm.classList.remove('is-demo'); smShade(); });
smRows().forEach(function (row) {
  row.addEventListener('click', function () {
    sm.classList.remove('is-demo');
    row.classList.toggle('is-pick');
    row.setAttribute('aria-selected', row.classList.contains('is-pick') ? 'true' : 'false');
    smSum();
  });
});
smSum(); smShade();

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

export type SummaryRow = { name: string; value: number };

export type StickySummaryRowProps = {
  gridLabel?: string;
  periodLabel?: string;
  amountLabel?: string;
  totalLabel?: string;
  rows?: SummaryRow[];
  /** 자동 재생 루프 (갤러리용). 사람이 손대면 꺼진다 */
  demo?: boolean;
  duration?: number;
  easing?: string;
  color?: string;
};

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

const ROWS: SummaryRow[] = [
  { name: "Mar wk 1", value: 42 },
  { name: "Mar wk 2", value: 38 },
  { name: "Mar wk 3", value: 51 },
  { name: "Mar wk 4", value: 27 },
  { name: "Apr wk 1", value: 60 },
];

export default function StickySummaryRow({
  gridLabel = "Settlement list",
  periodLabel = "Period",
  amountLabel = "Amount",
  totalLabel = "Total",
  rows = ROWS,
  demo = true,
  duration = 220,
  easing = "cubic-bezier(.2,.8,.2,1)",
  color = "#2f6df6",
}: StickySummaryRowProps) {
  const [picked, setPicked] = useState<number[]>([]);
  const [more, setMore] = useState(true);
  const [live, setLive] = useState(demo);
  const viewRef = useRef<HTMLDivElement>(null);

  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };

  // 고른 줄이 있으면 그것만, 없으면 전부 더한다
  const list = picked.length ? rows.filter((_r, i) => picked.indexOf(i) >= 0) : rows;
  const sum = list.reduce((n, r) => n + r.value, 0);
  // 루프에서 두 번째 줄만 골랐을 때 컷으로 갈아 끼우는 부분합
  const sample = rows.length > 1 ? rows[1].value : sum;

  // 끝까지 내려가면 그림자를 끈다
  const shade = () => {
    const el = viewRef.current;
    if (!el) return;
    setMore(el.scrollHeight - el.scrollTop - el.clientHeight > 2);
  };
  useEffect(() => { shade(); }, []);

  const toggle = (i: number) => {
    setLive(false);
    setPicked((prev) => (prev.indexOf(i) >= 0 ? prev.filter((n) => n !== i) : prev.concat([i])));
  };

  const cls = [styles.root, live ? styles.isDemo : "", more ? styles.isMore : ""].join(" ");

  return (
    <div className={cls} style={vars}>
      <div className={styles.head} role="row">
        <span role="columnheader">{periodLabel}</span>
        <span role="columnheader">{amountLabel}</span>
      </div>
      <div
        className={styles.view}
        role="grid"
        aria-label={gridLabel}
        tabIndex={0}
        ref={viewRef}
        onScroll={() => { setLive(false); shade(); }}
      >
        <div className={styles.track} role="rowgroup">
          {rows.map((r, i) => (
            <button
              key={r.name}
              className={[styles.row, picked.indexOf(i) >= 0 ? styles.isPick : ""].join(" ")}
              type="button"
              role="row"
              aria-selected={picked.indexOf(i) >= 0 ? "true" : "false"}
              onClick={() => toggle(i)}
            >
              <span role="gridcell">{r.name}</span>
              <span role="gridcell">{r.value}</span>
            </button>
          ))}
        </div>
        <div className={[styles.sum, picked.length ? styles.isPart : ""].join(" ")} role="row">
          <span className={styles.sic} aria-hidden="true">
            <svg viewBox="0 0 256 256" width="1em" height="1em" fill="currentColor">
              <g>
                <path d="M192 48v160H64l64-80l-64-80Z" opacity=".2" />
                <path d="M184 72V56H80.65l53.6 67a8 8 0 0 1 0 10l-53.6 67H184v-16a8 8 0 0 1 16 0v24a8 8 0 0 1-8 8H64a8 8 0 0 1-6.25-13l60-75l-60-75A8 8 0 0 1 64 40h128a8 8 0 0 1 8 8v24a8 8 0 0 1-16 0" />
              </g>
            </svg>
          </span>
          <span className={styles.label} role="gridcell">{totalLabel}</span>
          <span className={styles.v} role="gridcell">
            <b className={styles.all}>{sum}</b>
            <b className={styles.sel}>{sample}</b>
          </span>
        </div>
      </div>
    </div>
  );
}