/* ============================================================
   AI Engineering Notes — 개인 블로그
   단일 칼럼, 좌측 정렬, 장식 최소화
   ============================================================ */

:root {
  --paper: #fbfaf7;
  --paper-2: #f3f1ec;
  --ink: #1c1b18;
  --ink-soft: #4b4941;
  --ink-faint: #6f6c62;   /* 본문 대비 5:1 — WCAG AA 통과 */
  --rule: #e2dfd7;
  --link: #1b5e8c;
  --link-visited: #6b4a8c;
  --mark: #f0e6c8;

  /* 웹폰트를 쓰지 않습니다. 외부 요청 없이 바로 렌더되고, 한글은 각 OS의
     기본 서체로 떨어집니다. 세리프는 라틴 문자 위주인 제목에만 씁니다. */
  --serif: Charter, "Bitstream Charter", "Iowan Old Style", "Source Serif 4",
    Georgia, "Times New Roman", serif;
  --sans: -apple-system, BlinkMacSystemFont, "Pretendard", "Apple SD Gothic Neo",
    "Malgun Gothic", "Segoe UI", system-ui, sans-serif;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;

  --measure: 40rem;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #14140f;
    --paper-2: #1d1c17;
    --ink: #e8e4da;
    --ink-soft: #b3aea1;
    --ink-faint: #837e72;
    --rule: #2d2b24;
    --link: #7fb4d8;
    --link-visited: #b39ad0;
    --mark: #3a331c;
  }
}

:root[data-theme="dark"] {
  --paper: #14140f;
  --paper-2: #1d1c17;
  --ink: #e8e4da;
  --ink-soft: #b3aea1;
  --ink-faint: #837e72;
  --rule: #2d2b24;
  --link: #7fb4d8;
  --link-visited: #b39ad0;
  --mark: #3a331c;
}

/* ---- 기본 ---------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition-duration: .01ms !important; }
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.75;
  word-break: keep-all;       /* 한국어가 단어 중간에서 끊기지 않도록 */
  overflow-wrap: break-word;
  -webkit-font-smoothing: antialiased;
}

p { margin: 0 0 1.1em; }
p:last-child { margin-bottom: 0; }

a { color: var(--link); text-decoration: underline; text-underline-offset: 2px; text-decoration-thickness: 1px; }
a:hover { text-decoration-thickness: 2px; }
a:visited { color: var(--link-visited); }

em { font-style: normal; background: var(--mark); padding: 0 .15em; }

:focus-visible { outline: 2px solid var(--link); outline-offset: 2px; }

.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

.skip-link {
  position: absolute; left: 1rem; top: 0; transform: translateY(-150%);
  background: var(--paper); color: var(--ink); border: 1px solid var(--rule);
  padding: .5rem 1rem; z-index: 10; transition: transform .15s ease;
}
.skip-link:focus { transform: translateY(.5rem); }

.shell {
  max-width: var(--measure);
  margin: 0 auto;
  padding: 0 1.5rem 4rem;
}

/* ---- 머리말 -------------------------------------------- */
.masthead {
  display: flex; flex-wrap: wrap; align-items: baseline; gap: .75rem 1.25rem;
  padding: 3rem 0 2rem;
}

.site-title {
  font-family: var(--serif);
  font-size: 1.4rem;
  font-weight: 600;
  color: var(--ink);
  text-decoration: none;
  letter-spacing: -0.01em;
  margin-right: auto;
}
.site-title:visited { color: var(--ink); }
.site-title:hover { text-decoration: underline; text-underline-offset: 3px; }

.masthead nav {
  display: flex; align-items: center; gap: 1rem;
  font-size: .9rem;
}
.masthead nav a { color: var(--ink-soft); text-decoration: none; }
.masthead nav a:visited { color: var(--ink-soft); }
.masthead nav a:hover { color: var(--ink); text-decoration: underline; text-underline-offset: 3px; }

.theme-toggle {
  background: none; border: 0; padding: 0; margin: 0;
  color: var(--ink-faint); font-size: .95rem; line-height: 1;
  cursor: pointer;
}
.theme-toggle:hover { color: var(--ink); }

/* ---- 인사 ---------------------------------------------- */
.intro { color: var(--ink-soft); padding-bottom: .5rem; }
.intro-links { font-size: .9rem; color: var(--ink-faint); }

/* ---- 섹션 ---------------------------------------------- */
section { margin-top: 3.25rem; }

.section-label {
  font-family: var(--mono);
  font-size: .78rem;
  font-weight: 400;
  letter-spacing: .02em;   /* 한글이 벌어지지 않도록 라틴용 자간은 쓰지 않습니다 */
  color: var(--ink-faint);
  margin: 0 0 1.25rem;
  padding-bottom: .5rem;
  border-bottom: 1px solid var(--rule);
}

/* ---- 글 목록 ------------------------------------------- */
.section-note {
  margin: -.5rem 0 1.5rem;
  font-size: .88rem;
  color: var(--ink-faint);
}

/* 직접 쓴 글을 연도별로 묶을 때 씁니다. */
.year {
  font-family: var(--mono);
  font-size: .8rem;
  color: var(--ink-faint);
  margin: 2rem 0 .75rem;
}
.year:first-of-type { margin-top: 0; }

.post-list { list-style: none; margin: 0; padding: 0; }

.post-list > li {
  display: grid;
  grid-template-columns: 3.75rem 1fr;
  gap: 0 1rem;
  padding: .85rem 0;
  border-top: 1px solid var(--rule);
}
.post-list > li:first-child { border-top: 0; padding-top: 0; }

.post-list time {
  font-family: var(--mono);
  font-size: .78rem;
  color: var(--ink-faint);
  padding-top: .42rem;
  white-space: nowrap;
}

/* 제목은 한글 비중이 높아 세리프 대신 본문 서체를 씁니다. */
.post-list a {
  font-size: 1.06rem;
  font-weight: 600;
  line-height: 1.5;
  letter-spacing: -0.012em;
  color: var(--ink);
  text-decoration: none;
}
.post-list a:visited { color: var(--ink-soft); }
.post-list a:hover { text-decoration: underline; text-underline-offset: 3px; }

.post-list p {
  margin: .25rem 0 0;
  font-size: .93rem;
  line-height: 1.65;
  color: var(--ink-soft);
}

/* 외부 기사일 때 출처 표시 */
.source {
  font-family: var(--mono);
  font-size: .72rem;
  color: var(--ink-faint);
  border: 1px solid var(--rule);
  padding: .05rem .35rem;
  margin-right: .4rem;
  white-space: nowrap;
}

.post-list .ad-row { display: block; border-top: 1px solid var(--rule); padding: 0; }

.more { margin-top: 1.75rem; font-size: .93rem; }

/* ---- 요즘 ---------------------------------------------- */
.now-list { list-style: none; margin: 0; padding: 0; }
.now-list li {
  display: grid;
  grid-template-columns: 3.75rem 1fr;
  gap: 0 1rem;
  padding: .5rem 0;
  color: var(--ink-soft);
  font-size: .97rem;
}
.now-list span {
  font-family: var(--mono);
  font-size: .74rem;
  letter-spacing: .02em;
  color: var(--ink-faint);
  padding-top: .35rem;
}
.now-note { margin-top: 1rem; font-size: .84rem; color: var(--ink-faint); }

/* ---- 광고 ---------------------------------------------- */
.ad-slot { margin: 2.5rem 0; }
.ad-slot:empty { display: none; }
.ad-slot ins { display: block; }

/* 광고가 실제로 렌더링될 때만 라벨을 붙입니다. */
.ad-slot:has(ins)::before,
.ad-slot[data-placeholder]::before {
  content: "광고";
  display: block;
  font-family: var(--mono);
  font-size: .66rem;
  letter-spacing: .12em;
  color: var(--ink-faint);
  margin-bottom: .4rem;
}
.ad-slot[data-placeholder] {
  min-height: 5rem;
  border: 1px dashed var(--rule);
  padding: .6rem;
  color: var(--ink-faint);
  font-family: var(--mono);
  font-size: .75rem;
}

.post-list .ad-row .ad-slot { margin: 1.25rem 0; }

/* ---- 꼬리말 -------------------------------------------- */
.colophon {
  margin-top: 4rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--rule);
  display: flex; flex-wrap: wrap; gap: .35rem 1.5rem;
  justify-content: space-between;
  font-size: .85rem;
  color: var(--ink-faint);
}
.colophon p { margin: 0; }
.colophon a { color: var(--ink-faint); }
.colophon a:visited { color: var(--ink-faint); }
.colophon a:hover { color: var(--ink); }

/* ---- 본문 페이지 (개인정보처리방침 등) ------------------ */
.prose h1 {
  font-family: var(--serif);
  font-size: 1.75rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  margin: 0 0 .35rem;
}
.prose .updated { font-size: .85rem; color: var(--ink-faint); margin-bottom: 2.5rem; }
.prose h2 {
  font-family: var(--serif);
  font-size: 1.15rem;
  font-weight: 600;
  margin: 2.25rem 0 .6rem;
}
.prose p, .prose li { color: var(--ink-soft); font-size: .97rem; }
.prose ul { padding-left: 1.1rem; margin: .6rem 0 1.1rem; }
.prose li { margin-bottom: .3rem; }
.prose .back { margin-top: 3rem; font-size: .9rem; }

/* ---- 좁은 화면 ----------------------------------------- */
@media (max-width: 34rem) {
  body { font-size: 16px; }
  .shell { padding: 0 1.25rem 3rem; }
  .masthead { padding: 2.25rem 0 1.5rem; }
  .post-list > li { grid-template-columns: 1fr; gap: .15rem; }
  .post-list time { padding-top: 0; }
  .now-list li { grid-template-columns: 1fr; gap: 0; }
  .now-list span { padding-top: 0; }
}

/* ---- 글 본문 (posts/*.html) ---------------------------- */
.post-date { font-family: var(--mono); font-size: .8rem; color: var(--ink-faint); margin-bottom: .5rem; }
.post-body h1 { font-family: var(--serif); font-size: clamp(1.6rem, 4vw, 2.1rem); margin: 0 0 .6rem; }
.post-lede { font-size: 1.02rem; color: var(--ink-soft); margin-bottom: 2rem; }
.post-body h2 { font-size: 1.25rem; margin: 2.5rem 0 .7rem; }
.post-body h3 { font-size: 1.08rem; margin: 2rem 0 .5rem; }
.post-body h4 { font-size: .98rem; margin: 1.5rem 0 .4rem; }
.post-body p { margin: 0 0 1.15em; }
.post-body ul, .post-body ol { padding-left: 1.2rem; margin: 0 0 1.15em; }
.post-body li { margin-bottom: .35rem; }
.post-body hr { border: 0; border-top: 1px solid var(--rule); margin: 2.5rem 0; }
.post-body blockquote {
  margin: 0 0 1.15em; padding: .2rem 0 .2rem 1rem;
  border-left: 2px solid var(--rule); color: var(--ink-faint);
}
.post-body code {
  font-family: var(--mono); font-size: .86em;
  background: var(--paper-2); padding: .1em .35em; border-radius: 3px;
}
.post-body pre {
  background: var(--paper-2); border: 1px solid var(--rule);
  padding: .9rem 1rem; overflow-x: auto; margin: 0 0 1.15em;
  font-size: .86rem; line-height: 1.6;
}
.post-body pre code { background: none; padding: 0; font-size: inherit; }
.post-body img { max-width: 100%; height: auto; }

/* ---- 글쓰기 페이지 (editor.html) ----------------------- */
.shell-wide { max-width: 52rem; }

.editor-title { font-family: var(--serif); font-size: 1.6rem; margin: 0 0 .4rem; }
.editor-lede { color: var(--ink-faint); font-size: .93rem; margin-bottom: 2rem; }

.panel { border: 1px solid var(--rule); margin-bottom: 1.25rem; background: var(--paper); }
.panel > summary, .panel-head {
  font-family: var(--mono); font-size: .78rem; letter-spacing: .02em;
  color: var(--ink-faint); padding: .7rem 1rem; margin: 0;
  border-bottom: 1px solid var(--rule); font-weight: 400;
}
.panel > summary { cursor: pointer; }
.panel > summary:hover { color: var(--ink); }
.panel-body { padding: 1rem; }

.field { margin-bottom: 1rem; }
.field:last-child { margin-bottom: 0; }
.field label { display: block; font-size: .85rem; color: var(--ink-soft); margin-bottom: .3rem; }
.field-row { display: flex; gap: 1rem; flex-wrap: wrap; }
.field-row .field { flex: 1 1 12rem; }

.panel input[type="text"], .panel input[type="password"],
.panel input[type="date"], .panel textarea {
  width: 100%; padding: .5rem .6rem;
  font-family: inherit; font-size: .95rem; color: var(--ink);
  background: var(--paper); border: 1px solid var(--rule);
}
.panel textarea { font-family: var(--mono); font-size: .88rem; line-height: 1.7; resize: vertical; }
.panel input:focus, .panel textarea:focus { outline: 0; border-color: var(--ink-faint); }

.check { display: flex; align-items: center; gap: .45rem; margin-top: .6rem; font-size: .88rem; color: var(--ink-soft); }
.check input { width: auto; }

.hint { font-size: .84rem; color: var(--ink-faint); margin: 0 0 .6rem; line-height: 1.6; }
.hint code { font-family: var(--mono); font-size: .95em; background: var(--paper-2); padding: 0 .25em; }
.hint.warn { margin: .6rem 0 0; }

.linkbtn {
  background: none; border: 0; padding: 0; cursor: pointer;
  font: inherit; color: var(--link); text-decoration: underline; text-underline-offset: 2px;
}

.actions { display: flex; gap: .6rem; flex-wrap: wrap; }
.btn-primary, .btn-plain {
  padding: .5rem 1.1rem; font: inherit; font-size: .92rem;
  border: 1px solid var(--rule); cursor: pointer;
  transition: border-color .15s ease, background .15s ease;
}
.btn-primary { background: var(--ink); color: var(--paper); border-color: var(--ink); }
.btn-primary:hover:not(:disabled) { opacity: .85; }
.btn-primary:disabled { opacity: .45; cursor: default; }
.btn-plain { background: transparent; color: var(--ink); }
.btn-plain:hover { background: var(--paper-2); border-color: var(--ink-faint); }

.log { list-style: none; margin: 1rem 0 0; padding: 0; font-family: var(--mono); font-size: .82rem; }
.log li { padding: .25rem 0; color: var(--ink-soft); }
.log li.is-ok { color: var(--ink); }
.log li.is-error { color: #b3261e; }
:root[data-theme="dark"] .log li.is-error { color: #f2938c; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .log li.is-error { color: #f2938c; }
}

.empty-note { font-size: .9rem; color: var(--ink-faint); }

/* ---- 편집기 탭 ----------------------------------------- */
.tabs { display: flex; gap: 0; margin-bottom: 1.25rem; border-bottom: 1px solid var(--rule); }
.tab {
  background: none; border: 0; border-bottom: 2px solid transparent;
  padding: .55rem .9rem; margin-bottom: -1px;
  font: inherit; font-size: .92rem; color: var(--ink-faint);
  cursor: pointer;
}
.tab:hover { color: var(--ink); }
.tab.is-active { color: var(--ink); border-bottom-color: var(--ink); }

/* 편집기 안 미리보기에서는 섹션 상단 여백을 없앱니다. */
.panel-body > .intro, .panel-body > .now { margin-top: 0; }