:root{
  --navy:#0d3f73;
  --blue:#2d78e8;
  --ink:#15243a;
  --muted:#617087;
  --line:#dce5ef;
  --soft:#f5f8fc;
  --white:#fff;
  --green:#1d8a4e;
  --green-bg:#e6f5ec;
  --amber:#9a6200;
  --amber-bg:#fff3d9;
  --red:#b42318;
  --red-bg:#fdeceb;
  --gray-bg:#eef1f5;
}
*{box-sizing:border-box}
body{margin:0;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;color:var(--ink);background:var(--soft);line-height:1.55}
a{color:var(--blue)}
.bar{background:var(--white);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:5}
.bar-inner{max-width:760px;margin:auto;padding:10px 16px;display:flex;align-items:center;justify-content:space-between;gap:12px}
.bar img{height:52px;display:block}
.bar .who{font-size:.9rem;color:var(--muted);display:flex;gap:12px;align-items:center}
.wrap{max-width:760px;margin:auto;padding:16px}
.wide{max-width:1100px}
h1{font-size:1.5rem;margin:8px 0 14px;letter-spacing:-.02em}
h2{font-size:1.15rem;margin:22px 0 10px}
h3{font-size:1rem;margin:0 0 6px}
.card{background:var(--white);border:1px solid var(--line);border-radius:14px;padding:16px;margin:0 0 14px}
.muted{color:var(--muted)}
.small{font-size:.88rem}
button,.btn{font:inherit;font-weight:700;border:0;border-radius:10px;padding:11px 16px;background:var(--navy);color:#fff;cursor:pointer;display:inline-block;text-decoration:none;text-align:center}
button.secondary,.btn.secondary{background:var(--white);color:var(--navy);border:1px solid var(--line)}
button.link{background:none;color:var(--blue);padding:0;font-weight:600}
button:disabled{opacity:.55;cursor:default}
input,select,textarea{font:inherit;width:100%;padding:10px 12px;border:1px solid var(--line);border-radius:10px;background:#fff;color:var(--ink)}
label{display:block;font-weight:700;font-size:.9rem;margin:12px 0 6px}
.row{display:flex;gap:10px;flex-wrap:wrap;align-items:center}
.row > *{flex:1 1 160px}
.err{color:var(--red);font-weight:600;margin-top:10px}
.tabs{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:12px}
.tabs button{background:var(--white);color:var(--navy);border:1px solid var(--line);padding:8px 12px}
.tabs button.on{background:var(--navy);color:#fff;border-color:var(--navy)}
.pages{display:grid;gap:8px}
.page{display:flex;justify-content:space-between;align-items:center;gap:10px;padding:10px 12px;border:1px solid var(--line);border-radius:10px;background:#fff}
.page .t{font-weight:600}
.page .actions{display:flex;gap:8px;align-items:center;flex:0 0 auto}
.page .actions .btn{padding:8px 12px;font-size:.9rem}
.btn,button{white-space:nowrap}
.page.next{border-color:var(--blue);box-shadow:0 0 0 2px rgba(45,120,232,.15)}
.chip{display:inline-block;font-size:.78rem;font-weight:800;padding:3px 9px;border-radius:999px;white-space:nowrap}
.chip.correct,.chip.mastered{background:var(--green-bg);color:var(--green)}
.chip.careless,.chip.in_progress{background:var(--amber-bg);color:var(--amber)}
.chip.method,.chip.teacher{background:var(--red-bg);color:var(--red)}
.chip.needs_review,.chip.blank,.chip.todo{background:var(--gray-bg);color:var(--muted)}
.next-box{border-left:4px solid var(--blue);background:#eef5ff;padding:12px 14px;border-radius:8px;margin:10px 0}
.next-box.mastered{border-color:var(--green);background:var(--green-bg)}
.next-box.teacher{border-color:var(--red);background:var(--red-bg)}
.score{font-size:2rem;font-weight:800;letter-spacing:-.03em}
.problems{display:grid;gap:8px}
.problem{border:1px solid var(--line);border-radius:10px;padding:10px 12px;background:#fff}
.problem .head{display:flex;justify-content:space-between;gap:8px;align-items:center}
.problem .exp{margin:6px 0 0;font-size:.94rem}
.photo{max-width:100%;border-radius:10px;border:1px solid var(--line)}
.spinner{width:28px;height:28px;border:3px solid var(--line);border-top-color:var(--navy);border-radius:50%;animation:spin 1s linear infinite;margin:0 auto 10px}
@keyframes spin{to{transform:rotate(360deg)}}
.center{text-align:center}
.tips{font-size:.9rem;color:var(--muted);margin:8px 0 0;padding-left:18px}
table{width:100%;border-collapse:collapse;font-size:.92rem}
th,td{text-align:left;padding:8px;border-bottom:1px solid var(--line);vertical-align:top}
th{font-size:.8rem;color:var(--muted);text-transform:uppercase;letter-spacing:.04em}
a.page{text-decoration:none;color:var(--ink)}
.queue{display:grid;gap:8px;margin-top:12px}
.qitem{display:flex;gap:12px;align-items:center;padding:8px;border:1px solid var(--line);border-radius:10px;background:#fff}
.qitem img{width:64px;height:84px;object-fit:cover;border-radius:6px;flex:0 0 auto;border:1px solid var(--line)}
.qitem .qbody{flex:1;min-width:0}
.qitem .t{font-weight:600}
.small-btn{padding:6px 10px !important;font-size:.85rem}
.spinner.inline{display:inline-block;width:14px;height:14px;border-width:2px;margin:0 6px -2px 0}
.overview{display:grid;gap:8px;margin:10px 0 4px}
.ov-row{display:flex;gap:10px;align-items:flex-start;padding:10px 12px;border-radius:10px}
.ov-row b{display:block;font-size:.9rem}
.ov-icon{flex:0 0 26px;height:26px;border-radius:50%;display:grid;place-items:center;font-weight:900;color:#fff}
.ov-row.mastered{background:var(--green-bg)}.ov-row.mastered .ov-icon{background:var(--green)}
.ov-row.careless{background:var(--amber-bg)}.ov-row.careless .ov-icon{background:var(--amber)}
.ov-row.not_mastered{background:var(--red-bg)}.ov-row.not_mastered .ov-icon{background:var(--red)}
.marked{position:relative;line-height:0}
.marked .photo{width:100%;display:block}
.mk{position:absolute;pointer-events:none;line-height:1}
.mk.tick{color:#16a34a;font-weight:900;font-size:clamp(18px,5vw,40px);transform:translate(0,-55%);text-shadow:0 0 3px #fff}
.mk.ring{border:3px solid #dc2626;border-radius:50%;box-sizing:border-box}
.mk.ring.review{border-color:#d97706;border-style:dashed}
.mk.ring.blank{border-style:dashed}
.pager{display:flex;justify-content:space-between;gap:10px;margin:14px 0}
.pager .btn{flex:1}
.pagechips{display:flex;gap:6px;overflow-x:auto;padding-bottom:4px;margin:0 0 12px}
.pagechips a{flex:0 0 auto;text-decoration:none;font-size:.85rem;font-weight:700;padding:6px 10px;border-radius:999px;border:1px solid var(--line);background:#fff;color:var(--ink)}
.pagechips a.on{background:var(--navy);color:#fff;border-color:var(--navy)}
.hidden{display:none !important}
@media (max-width:520px){.bar img{height:42px}.score{font-size:1.6rem}}