/* 中受国語クイズ — About・学習コラム 共通スタイル */
:root{--brand:#2e8bc0;--brand-d:#1b6cb0;--ink:#26323a;--sub:#5b6b78;--line:#e2e9ef;--bg:#f3f7fa}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","Hiragino Kaku Gothic ProN","Noto Sans JP",sans-serif;line-height:1.85;-webkit-text-size-adjust:100%}
.wrap{max-width:760px;margin:0 auto;padding:18px 16px 64px}
.nav{display:flex;flex-wrap:wrap;gap:8px;align-items:center;margin-bottom:14px}
.nav a{display:inline-block;background:#fff;border:1px solid #cfd9e2;border-radius:999px;padding:7px 15px;color:#33566f;text-decoration:none;font-weight:700;font-size:.84rem}
.nav a:hover{background:#eef4fa}
.nav a.home{background:var(--brand);color:#fff;border-color:var(--brand)}
.card{background:#fff;border:1px solid var(--line);border-radius:16px;padding:24px 24px 28px;margin-bottom:16px}
h1{font-size:1.55rem;line-height:1.4;margin:.1em 0 .3em;color:var(--brand-d)}
h2{font-size:1.18rem;margin:1.8em 0 .5em;color:var(--brand-d);border-bottom:2px solid #e8f0f7;padding-bottom:5px}
h3{font-size:1.02rem;margin:1.4em 0 .3em;color:#2a3b47}
.lead{color:var(--sub);font-size:.96rem;margin:.2em 0 1em}
p,li{font-size:.97rem}
ul,ol{padding-left:1.3em}
li{margin:.25em 0}
a{color:var(--brand-d)}
table{border-collapse:collapse;width:100%;margin:.6em 0;font-size:.92rem;overflow:hidden;border-radius:10px}
th,td{border:1px solid var(--line);padding:8px 10px;text-align:left;vertical-align:top}
th{background:#eef4fa;color:#2a3b47;white-space:nowrap}
tr:nth-child(even) td{background:#f8fbfd}
.muted{color:var(--sub);font-size:.86rem}
.tip{background:linear-gradient(135deg,#eef6ff,#f6fbff);border:1px solid #cfe0ee;border-radius:12px;padding:12px 15px;margin:1em 0}
.cta{display:inline-block;background:var(--brand);color:#fff;text-decoration:none;border-radius:999px;padding:11px 22px;font-weight:800;font-size:.95rem;margin:.4em 0}
.cta:hover{background:var(--brand-d)}
.col-grid{display:grid;gap:12px}
.col-item{display:block;border:1px solid var(--line);border-radius:12px;padding:14px 16px;text-decoration:none;color:inherit;background:#fff;transition:.15s}
.col-item:hover{border-color:#bcd6ea;background:#fbfdff}
.col-item .t{font-weight:800;color:var(--brand-d);font-size:1.02rem}
.col-item .d{color:var(--sub);font-size:.88rem;margin-top:3px}
.foot{text-align:center;color:#9aa6b2;font-size:.78rem;margin-top:18px;line-height:1.8}
.foot a{color:#7c8a96}