/* UtilBox 공용 스타일.
   방향: 계측기 라벨. 흰 종이, 먹색 글자, 가는 괘선, 강조색은 인주 빨강 하나.
   본문은 시스템 한글 산세리프(웹폰트 없음, 속도 우선), 수치·라벨은 고정폭.
   카드·그림자·둥근 상자를 쓰지 않는다. 위계는 굵기·크기·괘선으로 만든다. */
:root {
  --paper: #ffffff;
  --paper-2: #f5f5f3;
  --ink: #141414;
  --ink-2: #4a4a48;
  --ink-3: #7c7c78;
  --rule: #dcdcd8;
  --rule-strong: #141414;
  --seal: #c8341c;
  --seal-ink: #ffffff;
  --seal-soft: #fbece8;
  --danger: #b3261e;
  --ok: #1d6b3a;
  --sans: -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Pretendard", "Malgun Gothic", "Noto Sans KR", "Segoe UI", sans-serif;
  --mono: ui-monospace, "SF Mono", "D2Coding", Menlo, Consolas, "Liberation Mono", monospace;
  --gutter: 16px;
  --wide: 880px;
  --measure: 640px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --paper: #111110;
    --paper-2: #1a1a19;
    --ink: #ededea;
    --ink-2: #b8b8b3;
    --ink-3: #8a8a85;
    --rule: #2e2e2c;
    --rule-strong: #ededea;
    --seal: #ff6a4d;
    --seal-ink: #1a0703;
    --seal-soft: #2a1510;
    --danger: #ff8a80;
    --ok: #7ed49b;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 16px/1.65 var(--sans);
  overflow-x: hidden;
  word-break: keep-all;
  overflow-wrap: anywhere;
}
a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { color: var(--seal); }
:focus-visible { outline: 2px solid var(--seal); outline-offset: 2px; }
img, video, canvas { max-width: 100%; height: auto; }
.num, output, .mono { font-family: var(--mono); font-variant-numeric: tabular-nums; }

/* 뼈대: 헤더·도구는 넓게, 읽는 글은 좁게 */
.site-header, .page, .site-footer { width: 100%; max-width: var(--wide); margin: 0 auto; padding: 0 var(--gutter); }
.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 52px;
  border-bottom: 1px solid var(--rule);
}
.brand { display: inline-flex; align-items: center; gap: 8px; font-weight: 800; font-size: 15px; letter-spacing: -0.01em; text-decoration: none; }
.brand::before { content: ""; width: 12px; height: 12px; background: var(--seal); }
.lang-switch { font: 13px/1 var(--mono); }
.lang-switch a { margin-left: 14px; text-decoration: none; color: var(--ink-3); }
.lang-switch a[aria-current] { color: var(--ink); }

.crumbs { font-size: 13px; line-height: 1.4; color: var(--ink-3); margin: 20px 0 0; }
.crumbs a { color: var(--ink-3); text-decoration: none; }
.crumbs a:hover { color: var(--seal); }
h1 { font-size: clamp(30px, 6.4vw, 46px); line-height: 1.12; font-weight: 800; letter-spacing: -0.035em; margin: 10px 0 10px; max-width: var(--measure); }
h2 { font-size: 19px; line-height: 1.35; font-weight: 700; letter-spacing: -0.015em; margin: 0 0 10px; }
.lead { color: var(--ink-2); margin: 0 0 28px; max-width: var(--measure); font-size: 16px; }

/* 도구 판: 상자가 아니라 위아래 괘선 사이의 작업대 */
.tool-panel { margin: 0 0 40px; border-top: 2px solid var(--rule-strong); border-bottom: 1px solid var(--rule); padding: 0 0 24px; }
.panel-bar {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  padding: 8px 0 18px;
  font-size: 13px;
  line-height: 1.4;
  color: var(--ink-3);
}
.panel-bar .local::before { content: "● "; color: var(--ok); }
.tool-panel .row { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; }
.tool-panel label { display: block; font-size: 14px; color: var(--ink-2); margin-bottom: 4px; }
.tool-panel input[type="text"], .tool-panel input[type="number"], .tool-panel select, .tool-panel textarea {
  width: 100%;
  min-height: 46px;
  padding: 10px 12px;
  font: inherit;
  color: var(--ink);
  background: var(--paper);
  border: 1px solid var(--ink-3);
  border-radius: 2px;
}
.tool-panel input:focus, .tool-panel select:focus, .tool-panel textarea:focus { outline: none; border-color: var(--seal); box-shadow: 0 0 0 1px var(--seal); }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 18px;
  font: inherit;
  font-size: 15px;
  font-weight: 700;
  color: var(--paper);
  background: var(--ink);
  border: 1px solid var(--ink);
  border-radius: 2px;
  cursor: pointer;
  text-decoration: none;
  transition: background-color .12s, color .12s, border-color .12s;
}
.btn:hover { background: var(--seal); border-color: var(--seal); color: var(--seal-ink); }
.btn.secondary { color: var(--ink); background: transparent; border-color: var(--ink-3); }
.btn.secondary:hover { border-color: var(--seal); color: var(--seal); background: transparent; }
.btn:disabled { opacity: 0.45; cursor: not-allowed; }

/* 파일 놓는 곳: 점선 파스텔 대신 굵은 테두리의 넓은 표적 */
.dropzone {
  display: block;
  border: 1px solid var(--ink);
  padding: 36px 20px;
  cursor: pointer;
  background: var(--paper-2);
  transition: background-color .12s, border-color .12s;
}
.dropzone:hover { border-color: var(--seal); }
.dropzone.over { border-color: var(--seal); background: var(--seal-soft); box-shadow: inset 0 0 0 1px var(--seal); }
.dropzone:has(input:focus-visible) { outline: 2px solid var(--seal); outline-offset: 2px; }

.result { margin-top: 16px; padding: 16px 0; border-top: 1px solid var(--rule); }
.error { color: var(--danger); }
.ad-slot { min-height: 100px; margin: 0 0 40px; display: flex; align-items: center; justify-content: center; color: var(--ink-3); font: 11px/1 var(--mono); }

/* 읽는 글: 좁은 폭, 절마다 괘선 */
.explain, .faq, .related { max-width: var(--measure); }
.explain h2 { padding-top: 22px; border-top: 1px solid var(--rule); margin-top: 28px; }
.explain h2:first-child { margin-top: 0; }
.explain p { margin: 0 0 12px; color: var(--ink-2); }
.explain strong { color: var(--ink); }

.faq { margin-top: 48px; }
.faq h2, .related h2 { font-size: 13px; font-weight: 700; color: var(--ink-3); letter-spacing: 0; padding-bottom: 10px; border-bottom: 2px solid var(--rule-strong); margin: 0; }
.faq details { border-bottom: 1px solid var(--rule); }
.faq summary { cursor: pointer; font-weight: 700; padding: 14px 32px 14px 0; list-style: none; position: relative; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; position: absolute; right: 4px; top: 12px; font: 400 20px/1 var(--mono); color: var(--ink-3); }
.faq details[open] summary::after { content: "−"; color: var(--seal); }
.faq summary:hover { color: var(--seal); }
.faq details p { margin: 0 0 16px; color: var(--ink-2); }

.related { margin-top: 48px; }
.related ul { list-style: none; padding: 0; margin: 0; }
.related li { border-bottom: 1px solid var(--rule); }
.related a { display: block; padding: 12px 0; text-decoration: none; font-weight: 600; }

/* 홈 목록 */
.tool-grid { list-style: none; padding: 0; margin: 0 0 32px; border-top: 2px solid var(--rule-strong); }
.tool-grid li { border-bottom: 1px solid var(--rule); }
.tool-card { display: grid; grid-template-columns: minmax(0, 1fr); gap: 2px; padding: 16px 0; text-decoration: none; }
.tool-card strong { font-size: 18px; letter-spacing: -0.01em; }
.tool-card span { font-size: 14px; color: var(--ink-2); }
.tool-card:hover strong { color: var(--seal); }
.page > h2 { font-size: 13px; line-height: 1.4; color: var(--ink-3); margin: 8px 0 8px; }

.site-footer { margin-top: 64px; padding: 20px var(--gutter) 40px; border-top: 1px solid var(--rule); color: var(--ink-3); font-size: 13px; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
@media (prefers-reduced-motion: reduce) { * { transition: none !important; } }

/* 홈 */
.home-title { font-size: clamp(34px, 8vw, 60px); margin-top: 36px; }
.promises { list-style: none; padding: 0; margin: -8px 0 40px; display: flex; flex-wrap: wrap; gap: 6px 0; font-size: 14px; color: var(--ink-2); }
.promises li:not(:last-child)::after { content: "·"; margin: 0 10px; color: var(--ink-3); }

/* 이어서 하기: 결과가 생기면 도구 판 아래에 나타난다 */
.next-step { margin-top: 20px; padding-top: 14px; border-top: 1px solid var(--rule); }
.next-step p { margin: 0 0 10px; font-size: 14px; }
.next-step p span { color: var(--ink-3); margin-left: 6px; }
.next-step .row { gap: 8px; }