:root{--pt-ink:#1d2430;--pt-dim:#5d6875;--pt-line:#dfe4ea;--pt-bg:#f7f8fa;--pt-card:#fff;--pt-accent:#0f5c8c;--pt-soft:#e8f1f7;--pt-warn:#a4501f;--pt-ok:#2e7d4f}
body.pt-page{margin:0;background:var(--pt-bg);color:var(--pt-ink);font:16px/1.6 Arial,"Yu Gothic","Hiragino Sans","PingFang SC",sans-serif}
.pt-nav{position:sticky;top:0;z-index:50;display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:8px 16px;
 background:#fff;border-bottom:1px solid var(--pt-line);padding:8px 16px;font:14px/1.4 Arial,sans-serif;color:var(--pt-ink)}
.pt-nav a{color:var(--pt-accent);text-decoration:none}.pt-nav a:hover{text-decoration:underline}
.pt-crumbs span{color:var(--pt-dim)}
.pt-pin{display:flex;align-items:center;gap:6px;flex-wrap:wrap}
.pt-pin input{font:inherit;width:9em;padding:4px 8px;border:1px solid var(--pt-line);border-radius:6px}
.pt-pin button,.pt-fbbox button,.pt-gateform button,#pt-all button{font:inherit;padding:5px 12px;border:1px solid var(--pt-accent);border-radius:6px;background:var(--pt-accent);color:#fff;cursor:pointer}
.pt-pin button.pt-quiet,.pt-fbbox button.pt-quiet{background:#fff;color:var(--pt-accent)}
.pt-pin .pt-on{color:var(--pt-ok);font-weight:700}
.pt-msg{font-size:13px;color:var(--pt-warn)}
.pt-main{max-width:1000px;margin:0 auto;padding:28px 16px 80px}
.pt-main h1{font-size:30px;line-height:1.2;margin:6px 0 8px}.pt-main h2{font-size:20px;margin:36px 0 12px;padding-bottom:6px;border-bottom:2px solid var(--pt-line)}
.pt-kicker{font-size:13px;letter-spacing:.12em;text-transform:uppercase;color:var(--pt-warn);font-weight:700;margin:0}
.pt-lead{color:var(--pt-dim);max-width:72ch}.pt-dim{color:var(--pt-dim);font-size:14px}
.pt-note{background:#fff7ef;border:1px solid #f0d6bd;border-radius:10px;padding:12px 14px}
.pt-cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:16px;margin:20px 0}
a.pt-card{display:block;background:var(--pt-card);border:1px solid var(--pt-line);border-radius:12px;padding:18px;text-decoration:none;color:inherit}
a.pt-card:hover{border-color:var(--pt-accent)}a.pt-card h3{margin:6px 0 4px;font-size:18px}a.pt-card p{margin:0;color:var(--pt-dim);font-size:14px}
.pt-tag{display:inline-block;font-size:12px;font-weight:700;color:var(--pt-accent);background:var(--pt-soft);border-radius:6px;padding:2px 8px}
.pt-docs{padding-left:20px}.pt-docs li{margin:4px 0}.pt-steps li{margin:4px 0}
.pt-wrap{overflow-x:auto}
table.pt-weeks{width:100%;border-collapse:collapse;background:#fff;font-size:14px;border:1px solid var(--pt-line)}
table.pt-weeks th,table.pt-weeks td{border-top:1px solid var(--pt-line);padding:8px 10px;text-align:left;vertical-align:top}
table.pt-weeks th{background:var(--pt-soft)}.pt-wk{white-space:nowrap;font-weight:700}
.pt-kind{display:inline-block;font-size:12px;border-radius:5px;padding:1px 6px;background:#eef0f3;color:var(--pt-dim)}
.pt-kind.pt-task,.pt-kind.pt-exam{background:#fde9dc;color:var(--pt-warn);font-weight:700}
.pt-lock{border:1px dashed #c9cfd6;border-radius:10px;padding:12px 14px;margin:10px 0;color:var(--pt-dim);font-size:14px;background:#fafbfc}
.pt-review{border:2px solid #e9c46a;border-radius:10px;padding:4px 12px 10px;margin:10px 0;background:#fffdf5}
.pt-review-tag{font-size:12px;font-weight:700;color:#8a6a00;margin:6px 0}
.pt-sample{background:var(--pt-soft);border-radius:8px;padding:8px 12px}
.pt-fb{margin:18px 0 6px}
.pt-fbbox{background:#fff;border:1px solid var(--pt-line);border-left:4px solid var(--pt-accent);border-radius:10px;padding:12px 14px;font:15px/1.5 Arial,sans-serif;color:var(--pt-ink)}
.pt-fbbox h3{margin:0 0 4px;font-size:16px}.pt-fbbox .pt-hint{margin:0 0 10px;color:var(--pt-dim);font-size:13px}
.pt-fbbox label{display:block;font-size:13px;color:var(--pt-dim);margin:8px 0 2px}
.pt-fbbox input,.pt-fbbox select,.pt-fbbox textarea{font:inherit;width:100%;box-sizing:border-box;padding:6px 8px;border:1px solid var(--pt-line);border-radius:6px}
.pt-fbbox textarea{min-height:90px;resize:vertical}
.pt-fbbox .pt-row{display:flex;gap:10px;align-items:center;margin-top:8px;flex-wrap:wrap}
.pt-locked-fb{color:var(--pt-dim);font-size:13px;border-top:1px solid var(--pt-line);padding-top:8px}
.pt-c{border-top:1px solid var(--pt-line);padding:8px 0}.pt-c:first-child{border-top:0}
.pt-meta{font-size:12px;color:var(--pt-dim)}.pt-text{white-space:pre-wrap;margin-top:2px}
.pt-c .pt-acts button{font-size:12px;padding:2px 8px;margin-right:6px}
.pt-status{font-size:11px;border-radius:4px;padding:0 5px;background:#eef0f3}
.pt-gate{text-align:center}.pt-gateform{display:flex;justify-content:center;gap:8px;margin-top:16px;flex-wrap:wrap}
.pt-gateform input{font:inherit;padding:6px 10px;border:1px solid var(--pt-line);border-radius:6px}
#pt-all .pt-group{margin:18px 0}#pt-all h3{margin:0 0 4px;font-size:16px}
#pt-all .pt-filters{display:flex;gap:8px;flex-wrap:wrap;align-items:center;margin:10px 0}
#pt-all select{font:inherit;padding:4px 8px}
@media (max-width:600px){.pt-main h1{font-size:24px}.pt-pin input{width:7em}}
/* course hub: one card per week, grouped by term (layout of the Japanese lessons hub) */
.hub{width:min(1000px,calc(100% - 32px));margin:24px auto 64px;background:#fff;border:1px solid var(--pt-line);border-radius:18px;box-shadow:0 18px 48px rgba(29,36,48,.07);overflow:hidden}
.hub-head{padding:40px 40px 30px;border-bottom:1px solid var(--pt-line);background:linear-gradient(135deg,rgba(15,92,140,.10),rgba(164,80,31,.06) 70%),#fff}
.hub-head h1{margin:0 0 8px;font-size:32px;line-height:1.15}.hub-head h1 .jp{color:var(--pt-accent)}
.hub-head .subtitle{margin:0;color:var(--pt-dim)}
.hub-sect{border-bottom:1px solid var(--pt-line)}.hub-sect:last-of-type{border-bottom:0}
.hub-sect>summary{list-style:none;cursor:pointer;padding:22px 40px;display:grid;grid-template-columns:12px 1fr auto;column-gap:11px;align-items:center}
.hub-sect>summary::-webkit-details-marker{display:none}.hub-sect>summary::marker{content:""}
.hub-sect>summary:hover{background:var(--pt-bg)}
.hub-dot{width:12px;height:12px;border-radius:4px;background:var(--pt-accent);grid-column:1;grid-row:1}.hub-dot.alt{background:var(--pt-warn)}
.hub-stitle{grid-column:2;grid-row:1;font-size:21px;font-weight:700}
.hub-slead{grid-column:2;grid-row:2;color:var(--pt-dim);font-size:14px;margin-top:2px}
.hub-chev{grid-column:3;grid-row:1;font-size:12.5px;font-weight:700;color:var(--pt-accent);white-space:nowrap;border:1px solid var(--pt-line);border-radius:999px;padding:6px 14px}
.hub-chev::after{content:"open ▾"}.hub-sect[open]>summary .hub-chev::after{content:"close ▴"}
.hub-body{padding:0 40px 28px}
.hub-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:14px}
a.hub-card{display:flex;flex-direction:column;gap:4px;padding:18px 20px;border:1px solid var(--pt-line);border-radius:14px;background:#fff;text-decoration:none;color:var(--pt-ink);transition:transform .15s,border-color .15s,box-shadow .15s}
a.hub-card:hover{transform:translateY(-2px);border-color:var(--pt-accent);box-shadow:0 10px 26px rgba(29,36,48,.08)}
.hub-wk{font-size:13px;font-weight:700;color:var(--pt-accent)}
.hub-kind{align-self:flex-start;font-size:12px;border-radius:5px;padding:1px 7px;background:#eef0f3;color:var(--pt-dim)}
.hub-kind.hub-task,.hub-kind.hub-exam{background:#fde9dc;color:var(--pt-warn);font-weight:700}
.hub-title{font-size:17px;font-weight:700;line-height:1.35}
.hub-desc{font-size:13.5px;color:var(--pt-dim);flex:1}
.hub-open{font-size:13px;font-weight:700;color:var(--pt-accent);margin-top:6px}
.hub-docs{margin:18px 0 0;padding-left:20px}.hub-docs li{margin:4px 0}
@media(max-width:720px){.hub{width:100%;margin:0;border-radius:0;border-left:0;border-right:0}.hub-head{padding:26px 20px}
  .hub-sect>summary{padding:18px 20px}.hub-body{padding:0 20px 22px}.hub-grid{grid-template-columns:1fr}.hub-head h1{font-size:26px}
  .hub-slead{grid-column:2/4}}
/* week page */
.wk-bar{display:flex;flex-wrap:wrap;gap:8px;align-items:center;justify-content:space-between;margin:16px auto 0;width:min(1000px,calc(100% - 32px))}
.wk-bar a.wk-btn{display:inline-flex;align-items:center;min-height:40px;padding:6px 14px;border-radius:10px;border:1px solid var(--pt-line);background:#fff;color:var(--pt-accent);font-weight:700;text-decoration:none}
.wk-bar a.wk-btn.primary{background:var(--pt-accent);border-color:var(--pt-accent);color:#fff}
.wk-bar .wk-nav{display:flex;gap:8px;flex-wrap:wrap}