/* コラム（記事一覧・記事ページ）共通のスタイル。トップページと同じ色・フォント */
:root {
  --bg: #fdfbff;
  --surface: #ffffff;
  --soft: #f4effb;
  --ink: #3a3550;
  --muted: #6e6880;
  --accent: #d63f87;
  --accent-dark: #b8306f;
  --navy: #4a3d7d;
  --mint: #4e9e86;
  --line: #ebe4f5;
  --line-green: #06c755;
  --shadow: 0 8px 30px rgba(60, 40, 110, .07);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0; background: var(--bg); color: var(--ink);
  font-family: "Noto Sans JP", system-ui, sans-serif; line-height: 1.9; font-size: 16px;
}
a { color: var(--accent-dark); }
img { max-width: 100%; display: block; }
.ko { font-family: "Noto Sans KR", sans-serif; word-break: keep-all; }
.nw { white-space: nowrap; }
.wrap { width: min(1080px, 100% - 32px); margin-inline: auto; }
.narrow { width: min(760px, 100% - 32px); margin-inline: auto; }
h1, h2, h3 { font-family: "Zen Maru Gothic", sans-serif; line-height: 1.5; text-wrap: balance; }
p, li { text-wrap: pretty; }

/* ---------- header / footer ---------- */
header {
  position: sticky; top: 0; z-index: 10; background: rgba(253, 251, 255, .94);
  backdrop-filter: blur(8px); border-bottom: 1px solid var(--line);
}
header .wrap { display: flex; align-items: center; justify-content: space-between; height: 64px; gap: 16px; }
.logo { display: inline-flex; align-items: center; text-decoration: none; }
.logo img { height: 42px; width: auto; display: block; }
.nav { display: flex; align-items: center; gap: 18px; font-size: 14px; font-weight: 700; }
.nav a { text-decoration: none; color: var(--ink); }
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  background: var(--accent); color: #fff !important; text-decoration: none; font-weight: 700;
  padding: 14px 28px; border-radius: 999px; transition: .2s; box-shadow: 0 6px 16px rgba(214, 63, 135, .3);
}
.btn:hover { background: var(--accent-dark); transform: translateY(-2px); }
.btn.sm { padding: 8px 18px; font-size: 14px; box-shadow: none; }
.btn.line { background: var(--line-green); box-shadow: 0 6px 16px rgba(6, 199, 85, .3); }
footer { background: var(--ink); color: #b9b6c2; font-size: 13px; padding: 32px 0; text-align: center; margin-top: 80px; }
footer a { color: #b9b6c2; margin: 0 10px; }
@media (max-width: 600px) { .nav .btn { display: none; } }

/* ---------- 記事一覧 ---------- */
.page-head { text-align: center; padding: 56px 0 32px; }
.page-head .label { color: var(--accent); font-weight: 700; letter-spacing: .15em; font-size: 14px; }
.page-head h1 { font-size: clamp(26px, 4.5vw, 36px); margin: 4px 0 8px; }
.page-head p { color: var(--muted); margin: 0; }
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 24px; }
.card {
  display: flex; flex-direction: column; background: var(--surface); border: 1px solid var(--line);
  border-radius: 18px; padding: 28px; text-decoration: none; color: var(--ink); box-shadow: var(--shadow); transition: .2s;
}
.card:hover { transform: translateY(-4px); box-shadow: 0 14px 36px rgba(214, 63, 135, .15); }
.card .cat { align-self: flex-start; background: var(--soft); color: var(--accent-dark); font-size: 12px; font-weight: 700; border-radius: 999px; padding: 2px 12px; }
.card h2 { font-size: 19px; margin: 12px 0 8px; }
.card p { color: var(--muted); font-size: 14px; margin: 0 0 16px; flex: 1; }
.card time { font-size: 12px; color: var(--muted); }

/* ---------- 記事ページ ---------- */
.crumbs { font-size: 12px; color: var(--muted); padding: 20px 0 0; }
.crumbs a { color: var(--muted); }
.article-head { padding: 24px 0 8px; }
.article-head .cat { display: inline-block; background: var(--soft); color: var(--accent-dark); font-size: 12px; font-weight: 700; border-radius: 999px; padding: 2px 12px; }
.article-head h1 { font-size: clamp(24px, 4.5vw, 34px); margin: 12px 0; }
.meta { display: flex; align-items: center; gap: 12px; font-size: 13px; color: var(--muted); }
.meta img { width: 40px; height: 40px; border-radius: 50%; object-fit: cover; object-position: 70% 22%; }
.article-body { background: var(--surface); border-radius: 20px; padding: 40px; margin-top: 24px; box-shadow: var(--shadow); }
.article-body h2 {
  font-size: clamp(20px, 3.4vw, 24px); margin: 48px 0 16px; padding: 10px 16px;
  background: var(--soft); border-left: 5px solid var(--accent); border-radius: 0 10px 10px 0;
}
.article-body h2:first-child { margin-top: 0; }
.article-body h3 { font-size: 19px; margin: 32px 0 8px; color: var(--navy); }
.article-body p { margin: 0 0 18px; }
.article-body ul, .article-body ol { padding-left: 1.4em; margin: 0 0 18px; }
.article-body strong { background: linear-gradient(transparent 62%, #ffd6ea 62%); }
.toc { background: var(--bg); border: 1px solid var(--line); border-radius: 14px; padding: 20px 24px; margin: 0 0 32px; }
.toc b { display: block; font-family: "Zen Maru Gothic"; margin-bottom: 4px; }
.toc ol { margin: 0; }
.toc a { color: var(--ink); text-decoration: none; }
/* 例文の囲み */
.ex-box { background: var(--bg); border-radius: 14px; padding: 16px 20px; margin: 0 0 20px; }
.ex-box p { margin: 0; }
.ex-box .ko { font-size: 18px; font-weight: 700; }
.ex-box .ja { color: var(--muted); font-size: 14px; margin-bottom: 8px; }
.ex-box .ja:last-child { margin-bottom: 0; }
/* ポイントの囲み */
.point { border: 2px solid var(--accent); border-radius: 14px; padding: 18px 22px; margin: 0 0 24px; }
.point b { color: var(--accent); font-family: "Zen Maru Gothic"; }
.point p:last-child { margin-bottom: 0; }
/* 表 */
.table-wrap { overflow-x: auto; margin: 0 0 24px; }
table { width: 100%; border-collapse: collapse; font-size: 15px; }
th, td { border: 1px solid var(--line); padding: 10px 12px; text-align: center; }
thead th { background: var(--navy); color: #fff; font-weight: 700; }
tbody th { background: var(--soft); }
td.ko { font-size: 17px; }
/* 講師のひとこと */
.teacher-note { display: flex; gap: 16px; align-items: flex-start; background: #f1eefa; border-radius: 14px; padding: 18px 20px; margin: 0 0 24px; }
.teacher-note img { width: 56px; height: 56px; border-radius: 50%; object-fit: cover; object-position: 70% 22%; flex-shrink: 0; }
.teacher-note b { display: block; color: var(--navy); font-size: 14px; }
.teacher-note p { margin: 0; font-size: 15px; }
/* 記事の最後の申し込み */
.cta-box { text-align: center; background: linear-gradient(135deg, #e4579c, #8b77c9); color: #fff; border-radius: 20px; padding: 36px 24px; margin-top: 40px; }
.cta-box h2 { background: none; border: none; padding: 0; margin: 0 0 8px; font-size: clamp(20px, 3.6vw, 24px); color: #fff; }
.cta-box p { margin: 0 0 20px; }
.related { margin-top: 48px; }
.related > h2 { font-size: 20px; text-align: center; margin-bottom: 20px; }

/* 公式（第Ⅲ語基＋ㅆ어요 など） */
.formula { display: flex; flex-wrap: wrap; align-items: center; justify-content: center; gap: 10px; background: linear-gradient(135deg, #fff0f7, #f1ecfb); border-radius: 18px; padding: 24px 16px; margin: 0 0 24px; font-weight: 700; }
.formula span { border-radius: 12px; padding: 6px 14px; font-size: 18px; }
.formula .f-gogi { background: var(--accent); color: #fff; }
.formula .f-end { background: #fff; color: var(--accent-dark); font-size: 22px; border: 2px solid #ffd6ea; }
.formula .f-res { background: var(--navy); color: #fff; }
.formula .f-plus, .formula .f-eq { padding: 0; color: var(--muted); font-size: 20px; }
/* よくある間違い */
.ng-list { display: grid; gap: 12px; margin: 0 0 24px; }
.ng-list > div { background: var(--bg); border-radius: 14px; padding: 16px 18px; display: grid; grid-template-columns: auto auto auto 1fr; gap: 6px 10px; align-items: center; }
.ng-list p { grid-column: 1 / -1; margin: 0; font-size: 14px; color: var(--muted); }
.ng-list .ng { font-size: 18px; font-weight: 700; color: #a8a2b8; text-decoration: line-through; text-decoration-color: var(--accent); }
.ng-list .ok { font-size: 20px; font-weight: 700; color: var(--accent); }
.ng-list .arrow { color: var(--muted); }
/* 練習問題（タップで答え） */
.quiz { display: grid; gap: 10px; margin: 0 0 28px; }
.quiz details { background: var(--bg); border: 1.5px solid var(--line); border-radius: 14px; padding: 0 18px; }
.quiz details[open] { border-color: var(--accent); background: #fff7fb; }
.quiz summary { cursor: pointer; list-style: none; padding: 14px 0; font-weight: 700; display: flex; align-items: center; gap: 12px; }
.quiz summary::-webkit-details-marker { display: none; }
.quiz summary::after { content: "答えを見る ›"; margin-left: auto; font-size: 12px; color: var(--accent-dark); }
.quiz details[open] summary::after { content: "閉じる"; }
.quiz .q-no { background: var(--accent); color: #fff; font-size: 12px; border-radius: 999px; padding: 1px 10px; }
.quiz summary .ko { font-size: 18px; }
.quiz details p { margin: 0 0 14px; font-size: 17px; }
.quiz details b { color: var(--accent); background: none; }

@media (max-width: 600px) {
  .article-body { padding: 24px 18px; border-radius: 16px; }
  .formula span { font-size: 15px; padding: 5px 10px; }
  .formula .f-end { font-size: 18px; }
  .card { padding: 22px; }
  table { font-size: 13px; }
  th, td { padding: 8px 6px; }
}