:root{
  --bg:#f4f5fb; --panel:#ffffff; --panel2:#f8f9fd; --line:#d9dfea; --muted:#6b7280;
  --text:#111827; --sub:#374151; --purple:#5b54f1; --purple2:#ecebff; --green:#12945a;
  --green-bg:#e7f8ef; --red:#d44c5a; --red-bg:#fff0f2; --yellow:#b7791f; --yellow-bg:#fff7df;
  --shadow:0 20px 48px rgba(86, 98, 131, .10);
}
*{box-sizing:border-box} body{margin:0;background:linear-gradient(180deg,var(--bg),#fbfcff);color:var(--text);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Noto Sans","PingFang SC","Microsoft YaHei",Arial,sans-serif;line-height:1.55}.app{max-width:1320px;margin:0 auto;padding:30px 18px 46px}
header{display:flex;justify-content:space-between;gap:20px;align-items:flex-start;margin-bottom:26px;padding:10px 2px}.brand{max-width:900px}.brand-badge{display:inline-flex;align-items:center;gap:10px;padding:14px 22px;border-radius:999px;background:var(--purple2);color:#4338ca;font-size:18px;font-weight:900;letter-spacing:-.02em;margin-bottom:28px}.brand h1{margin:0;font-size:78px;line-height:.98;letter-spacing:-.06em;color:#0f172a}.brand-quote{margin:24px 0 0;color:#64748b;font-size:30px;line-height:1.6;letter-spacing:-.02em}.brand-attribution{margin-top:10px;color:#64748b;font-size:20px;line-height:1.5}.top-actions{padding-top:8px}
.controls{display:grid;grid-template-columns:1.4fr 1fr 1fr .7fr;gap:12px;margin-bottom:16px}.controls input,.controls select{width:100%;background:#fff;border:1.5px solid var(--line);border-radius:18px;color:var(--text);padding:15px 16px;font-size:16px;outline:none}.controls input:focus,.controls select:focus{border-color:var(--purple);box-shadow:0 0 0 4px rgba(91,84,241,.08)}
.topline{display:flex;justify-content:space-between;gap:12px;align-items:center;margin:16px 0}.modebar,.actions{display:flex;gap:10px;flex-wrap:wrap}.btn{border:1.5px solid var(--line);background:#fff;color:var(--text);border-radius:18px;padding:12px 16px;font-weight:900;cursor:pointer;transition:.15s;font-size:15px;box-shadow:0 4px 12px rgba(86,98,131,.04)}.btn:hover{transform:translateY(-1px);border-color:#bfc8db}.btn.active,.btn.primary{background:linear-gradient(180deg,#6f69ff,var(--purple));color:#fff;border-color:transparent;box-shadow:0 10px 24px rgba(91,84,241,.25)}.btn.ghost{background:#fff}.btn.warn{background:var(--yellow-bg);color:var(--yellow);border-color:#f0dd97}.btn.small{padding:9px 12px;font-size:14px;border-radius:14px}.btn.danger{background:var(--red-bg);color:#a22834;border-color:#ffd2d8}
.layout{display:grid;grid-template-columns:320px 1fr;gap:18px}.sidebar,.card{background:var(--panel);border:1.5px solid var(--line);border-radius:28px;box-shadow:var(--shadow)}.sidebar{padding:16px;max-height:78vh;overflow:auto;background:linear-gradient(180deg,#fff,#fbfcff)}.card{min-height:650px;padding:28px;background:linear-gradient(180deg,#fff,#fcfcff)}
.statgrid{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-bottom:14px}.stat{background:var(--panel2);border:1px solid #e7ebf3;border-radius:18px;padding:12px 14px}.stat b{display:block;font-size:26px}.stat span{color:var(--muted);font-size:13px}.topic-card{background:#f7f8fc;border:1px solid #e5eaf4;border-radius:20px;padding:14px;margin-bottom:14px}.topic-card b{display:block;font-size:16px}.topic-card p{margin:6px 0 0;color:var(--muted);font-size:13px}.topiclist{display:flex;flex-direction:column;gap:10px}.family-btn{text-align:left;background:var(--panel2);border:1.5px solid #e5eaf4;color:var(--sub);border-radius:18px;padding:12px 13px;cursor:pointer}.family-btn strong{display:block;color:#111827;font-size:14px}.family-btn span{font-size:12px;color:var(--muted)}.family-btn.active{border-color:rgba(91,84,241,.45);background:var(--purple2)}
.meta{display:flex;flex-wrap:wrap;gap:10px;margin-bottom:16px}.pill{display:inline-flex;align-items:center;gap:6px;padding:7px 12px;border:1px solid #dde3ee;border-radius:999px;color:#4b5563;background:#f8f9fd;font-size:13px;font-weight:800}.pill.blue{border-color:#d7d5ff;color:#4338ca;background:#f0efff}.pill.green{border-color:#caeedc;color:#157347;background:#effcf5}.page-title{font-size:34px;line-height:1.2;margin:0 0 12px;letter-spacing:-.04em}.context{border-left:4px solid var(--purple);padding:14px 16px;color:var(--sub);font-size:17px;margin:14px 0 22px;background:linear-gradient(90deg,rgba(91,84,241,.07),rgba(91,84,241,.02));border-radius:0 18px 18px 0}.context b{color:#111827}
.pile{display:flex;flex-wrap:wrap;gap:10px;background:#f7f8fc;border:2px dashed #d9deeb;border-radius:24px;padding:16px;min-height:96px;margin:16px 0 22px}.chip{border:1.5px solid #dbe2ef;background:#fff;color:#1f2937;border-radius:999px;padding:12px 15px;cursor:grab;font-size:17px;font-weight:800;transition:.12s}.chip:hover{border-color:#b9c3d9;transform:translateY(-1px)}.chip.selected{background:var(--purple2);border-color:#c8c4ff;color:#352fbf}.chip.placed{opacity:.35}.chip .type{font-size:11px;color:#64748b;margin-left:6px}
.boxgrid{display:grid;grid-template-columns:repeat(2,minmax(260px,1fr));gap:14px}.dropbox{border:1.5px solid #dce3ef;border-radius:22px;padding:14px;min-height:160px;background:#fff}.dropbox.dragover{border-color:var(--purple);box-shadow:0 0 0 4px rgba(91,84,241,.08)}.dropbox h3{margin:0 0 6px;font-size:18px}.dropbox p{margin:0 0 10px;color:#6b7280;font-size:13px}.drop-items{display:flex;flex-wrap:wrap;gap:8px}.drop-items .chip{font-size:15px;padding:9px 12px;cursor:pointer}
.feedback{min-height:30px;font-weight:900;font-size:18px;margin:16px 0}.good{color:var(--green)}.bad{color:var(--red)}.explain{background:#f8f9fd;border:1px solid #e5eaf3;border-radius:20px;padding:16px;margin-top:14px}.explain h3{margin:0 0 8px}.explain ul{margin:8px 0 0;padding-left:20px}.choice-grid{display:grid;grid-template-columns:repeat(2,minmax(220px,1fr));gap:12px;margin-top:20px}.choice{border:1.5px solid #dce3ef;border-radius:20px;padding:16px;background:#fff;cursor:pointer;text-align:left;font-size:18px;font-weight:850}.choice:hover{border-color:#b9c3d9}.choice.correct{border-color:#9be7bd;background:var(--green-bg);color:#0b6b3c}.choice.incorrect{border-color:#ffb4bd;background:var(--red-bg);color:#a22834}.example{font-size:24px;line-height:1.55;margin:14px 0;color:#111827}.highlight{background:var(--purple2);border-radius:12px;padding:2px 8px;color:#4338ca;font-weight:900}.rewrite-box{width:100%;min-height:160px;border:1.5px solid #dce3ef;border-radius:22px;padding:16px;font-size:18px;line-height:1.55;resize:vertical;outline:none}.rewrite-box:focus{border-color:var(--purple);box-shadow:0 0 0 4px rgba(91,84,241,.08)}.review-grid{display:grid;grid-template-columns:repeat(2,minmax(260px,1fr));gap:14px}.family-card{background:#fff;border:1.5px solid #e0e6f0;border-radius:22px;padding:16px}.family-card h3{margin:0 0 8px}.family-card p{color:#6b7280;margin:0 0 12px}.footer-actions{display:flex;justify-content:space-between;align-items:center;gap:12px;border-top:1px solid #ebeff5;margin-top:24px;padding-top:18px}.progress{color:#6b7280;font-size:14px;font-weight:700}.hidden{display:none!important}.selected-note{color:#4338ca;font-weight:900}
@media(max-width:980px){.brand h1{font-size:58px}.controls{grid-template-columns:1fr 1fr}.layout{grid-template-columns:1fr}.sidebar{max-height:320px}.boxgrid,.review-grid,.choice-grid{grid-template-columns:1fr}}
@media(max-width:760px){header{display:block}.top-actions{margin-top:16px}.controls{grid-template-columns:1fr}.brand-badge{font-size:16px;padding:12px 18px;margin-bottom:20px}.brand h1{font-size:42px}.brand-quote{font-size:24px}.brand-attribution{font-size:17px}.card{padding:18px}.page-title{font-size:26px}.example{font-size:20px}.footer-actions{display:block}.footer-actions .actions{margin-bottom:12px}}

/* v3 round sorting optimisation */
.single-chip-zone{
  background:#f7f8fc;
  border:2px dashed #d9deeb;
  border-radius:26px;
  padding:18px;
  margin:16px 0 22px;
}
.single-chip-zone.done{
  border-style:solid;
  background:#f4fff8;
  border-color:#c6efda;
}
.single-label{
  color:#6b7280;
  font-size:14px;
  font-weight:900;
  margin-bottom:12px;
  text-transform:uppercase;
  letter-spacing:.04em;
}
.single-example{
  color:#64748b;
  font-size:15px;
  margin:12px 0 0;
}
.main-chip{
  font-size:27px;
  padding:16px 22px;
  border-radius:999px;
  max-width:100%;
  white-space:normal;
  text-align:left;
  cursor:grab;
}
.compact-boxgrid{
  grid-template-columns:repeat(2,minmax(260px,1fr));
}
.compact-boxgrid .dropbox{
  min-height:190px;
}
.compact-boxgrid .dropbox h3{
  font-size:20px;
}
.placed-chip{
  font-size:15px;
  padding:9px 12px;
  cursor:pointer;
}
.chip .type{display:none!important}
@media(max-width:980px){
  .compact-boxgrid{grid-template-columns:1fr}
  .main-chip{font-size:22px}
}


/* v4 compact sorting: keep the whole round on one screen */
.card{
  padding:18px !important;
}
.page-title{
  font-size:28px !important;
  margin-bottom:8px !important;
}
.context.compact-context{
  font-size:15px !important;
  padding:9px 12px !important;
  margin:8px 0 10px !important;
  border-radius:0 14px 14px 0 !important;
}
.single-chip-zone{
  padding:10px 12px !important;
  margin:8px 0 12px !important;
  border-radius:18px !important;
}
.single-label{
  font-size:12px !important;
  margin-bottom:6px !important;
}
.main-chip{
  font-size:22px !important;
  padding:10px 16px !important;
  line-height:1.25 !important;
}
.single-example{
  font-size:13px !important;
  line-height:1.35 !important;
  margin:8px 0 0 !important;
  max-height:3.1em;
  overflow:auto;
}
.compact-boxgrid{
  display:grid !important;
  grid-template-columns:repeat(auto-fit,minmax(220px,1fr)) !important;
  gap:10px !important;
}
.compact-boxgrid .dropbox{
  min-height:82px !important;
  padding:10px 12px !important;
  border-radius:16px !important;
}
.compact-boxgrid .dropbox h3{
  font-size:16px !important;
  line-height:1.2 !important;
  margin:0 0 3px !important;
}
.compact-boxgrid .dropbox p{
  font-size:12px !important;
  line-height:1.25 !important;
  margin:0 0 6px !important;
  display:-webkit-box;
  -webkit-line-clamp:2;
  -webkit-box-orient:vertical;
  overflow:hidden;
}
.drop-items{
  gap:6px !important;
}
.placed-chip{
  font-size:12px !important;
  padding:5px 8px !important;
}
.footer-actions{
  margin-top:12px !important;
  padding-top:12px !important;
}
.feedback{
  font-size:15px !important;
  margin:10px 0 !important;
  min-height:20px !important;
}
.explain{
  padding:12px !important;
  margin-top:10px !important;
  font-size:14px !important;
}
@media(max-width:980px){
  .compact-boxgrid{
    grid-template-columns:repeat(2,minmax(0,1fr)) !important;
  }
}
@media(max-width:620px){
  .compact-boxgrid{
    grid-template-columns:1fr !important;
  }
  .main-chip{
    font-size:20px !important;
  }
}


/* v6: click placed chips to return them */
.placed-chip{
  cursor:pointer !important;
  position:relative;
}
.placed-chip:hover{
  border-color:#f0b8c0 !important;
  background:#fff4f5 !important;
  color:#9f2430 !important;
  transform:translateY(-1px);
}
.undo-mark{
  font-weight:900;
  opacity:.65;
  margin-left:4px;
}
.returned-note{
  display:inline-flex;
  margin-left:12px;
  padding:6px 10px;
  border-radius:999px;
  background:#fff7df;
  border:1px solid #f0dd97;
  color:#9a5a00;
  font-size:13px;
  font-weight:900;
}
@media(max-width:620px){
  .returned-note{
    display:block;
    width:max-content;
    max-width:100%;
    margin:8px 0 0;
  }
}