.btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;border:1px solid var(--line);background:var(--surface);padding:9px 15px;border-radius:var(--r-s);cursor:pointer;font-weight:600;text-decoration:none;color:var(--fg);min-height:40px}
.btn:hover{background:var(--surface2)}.btn.pri{background:var(--btn,var(--pri));border-color:var(--btn,var(--pri));color:#fff}.btn.pri:hover{background:var(--btn,var(--pri-d));filter:brightness(.9)}
.btn.ghost{border-color:transparent;background:transparent}.btn.ghost:hover{background:var(--surface2)}.btn.sm{min-height:34px;padding:5px 11px;font-size:.88rem}
.btn.bad{color:var(--bad);border-color:var(--bad)}.btn[disabled],.btn[aria-disabled=true]{opacity:.55;cursor:not-allowed}
.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--r);padding:14px;box-shadow:var(--shadow)}
.card.pad0{padding:0;overflow:hidden}
.card h3{margin-bottom:.25em}
.chip{display:inline-flex;align-items:center;gap:4px;padding:2px 10px;border-radius:999px;background:var(--surface2);font-size:.78rem;font-weight:600;color:var(--mute)}
.chip.ok{background:var(--ok-t);color:var(--ok)}.chip.bad{background:var(--bad-t);color:var(--bad)}.chip.pri{background:var(--pri-t);color:var(--pri-d)}.chip.acc{background:var(--acc-t);color:var(--acc)}.chip.info{background:var(--info-t);color:var(--info)}
.tabs{display:flex;gap:4px;border-bottom:1px solid var(--line);margin-bottom:14px;overflow-x:auto;scrollbar-width:none}
.tabs button{border:0;background:none;padding:10px 14px;font-weight:700;color:var(--mute);cursor:pointer;border-bottom:3px solid transparent;white-space:nowrap}
.tabs button.on{color:var(--pri-d);border-color:var(--pri)}
.page-h{display:flex;align-items:flex-end;justify-content:space-between;gap:12px;flex-wrap:wrap;margin-bottom:14px}
.page-h p{margin:0;color:var(--mute)}
.empty{text-align:center;padding:36px 14px;color:var(--mute)}.empty .ic{font-size:2.2rem}.empty b{display:block;color:var(--fg);margin:4px 0}
label.f{display:flex;flex-direction:column;gap:4px;font-weight:600;font-size:.88rem}
input,select,textarea{padding:9px 11px;border:1px solid var(--line);border-radius:var(--r-s);background:var(--surface);width:100%;min-height:40px}
input[type=checkbox],input[type=radio]{width:auto;min-height:0}
textarea{min-height:90px;resize:vertical}
.form{display:grid;gap:12px}.form .two{display:grid;gap:12px;grid-template-columns:repeat(auto-fit,minmax(min(100%,230px),1fr))}.form .two>*{min-width:0}
.err{color:var(--bad);font-size:.88rem;min-height:1.2em}
.dlg{border:0;border-radius:var(--r);padding:20px;overflow-x:hidden;width:min(660px,calc(100vw - 24px));max-height:calc(100vh - 24px);background:var(--surface);color:var(--fg);box-shadow:0 20px 60px rgba(0,0,0,.35)}
.dlg.sm{width:min(480px,calc(100vw - 24px))}.dlg.lg{width:min(940px,calc(100vw - 24px))}
.dlg input,.dlg select,.dlg textarea{max-width:100%;min-width:0}.dlg label.f,.dlg .form>*{min-width:0}
.dlg::backdrop{background:rgba(10,20,18,.55)}
.askt{font-size:1.02rem;white-space:pre-line}
.toast{position:fixed;left:50%;bottom:calc(76px + env(safe-area-inset-bottom,0px));transform:translateX(-50%);z-index:90;background:#14211e;color:#fff;padding:10px 16px;border-radius:12px;max-width:min(92vw,520px);box-shadow:var(--shadow);font-weight:600}
/* kho bài */
.tools{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:12px}.tools .q{flex:1 1 220px}.tools select{flex:0 1 170px}
.pills{display:flex;gap:6px;overflow-x:auto;padding-bottom:6px;margin-bottom:10px;scrollbar-width:none}
.pill{border:1px solid var(--line);background:var(--surface);border-radius:999px;padding:6px 13px;font-weight:600;cursor:pointer;white-space:nowrap;color:var(--mute)}
.pill.on{background:var(--pri);border-color:var(--pri);color:#fff}
.ex{display:flex;flex-direction:column;gap:8px;min-height:150px}
.ex .hd{display:flex;gap:10px;align-items:flex-start}
.ex .ico{flex:none;width:44px;height:44px;border-radius:12px;display:grid;place-items:center;font-size:1.4rem}
.ex h3{margin:0;font-size:1rem}.ex .meta{display:flex;gap:6px;flex-wrap:wrap}
.ex .act{margin-top:auto;display:flex;gap:6px;flex-wrap:wrap}
/* thống kê */
.stats{display:grid;gap:10px;grid-template-columns:repeat(auto-fit,minmax(130px,1fr))}
.stat{background:var(--surface);border:1px solid var(--line);border-radius:var(--r);padding:12px}
.stat b{display:block;font-size:1.55rem;line-height:1.1}.stat span{color:var(--mute);font-size:.8rem}
.bar{height:10px;border-radius:999px;background:var(--surface2);overflow:hidden}.bar i{display:block;height:100%;background:var(--pri);border-radius:999px}
.bar.acc i{background:var(--acc)}
table.t{width:100%;border-collapse:collapse;font-size:.92rem}
table.t th,table.t td{padding:8px 10px;border-bottom:1px solid var(--line);text-align:left;vertical-align:middle}
table.t th{color:var(--mute);font-size:.78rem;text-transform:uppercase;letter-spacing:.04em}
.tw{overflow-x:auto}
.g1{color:var(--ok);font-weight:700}.g2{color:var(--acc);font-weight:700}.g3{color:var(--bad);font-weight:700}
/* hồ sơ học sinh */
.prof{display:grid;gap:14px;grid-template-columns:300px 1fr}@media(max-width:860px){.prof{grid-template-columns:1fr}}
.ava{width:76px;height:76px;border-radius:50%;background:var(--pri-t);display:grid;place-items:center;font-size:2.3rem}
.badge{display:flex;gap:10px;align-items:center;padding:8px 0;border-bottom:1px dashed var(--line)}.badge .bi{font-size:1.6rem;filter:grayscale(1);opacity:.4}.badge.on .bi{filter:none;opacity:1}
.hmap{display:grid;grid-template-columns:repeat(14,1fr);gap:3px}.hmap i{aspect-ratio:1;border-radius:3px;background:var(--surface2)}.hmap i.l1{background:var(--pri-t)}.hmap i.l2{background:#7cc9c0}.hmap i.l3{background:var(--pri)}
/* thi đấu */
.cup{display:flex;gap:12px;align-items:center}.cup .ci{font-size:2rem}
.rank{display:grid;grid-template-columns:34px 1fr auto;gap:10px;align-items:center;padding:10px 4px;border-bottom:1px solid var(--line)}
.rank .no{width:30px;height:30px;border-radius:50%;display:grid;place-items:center;font-weight:800;background:var(--surface2)}
.rank.r1 .no{background:#f6d365;color:#4a3300}.rank.r2 .no{background:#d9dfe3;color:#2b3236}.rank.r3 .no{background:#e8b48a;color:#4a2a0c}
.rank.me{background:var(--pri-t);border-radius:10px}
/* màn hình làm bài */
.viewer{position:fixed;inset:0;z-index:60;background:var(--bg);display:flex;flex-direction:column;padding-top:env(safe-area-inset-top,0px)}
.vbar{display:flex;align-items:center;gap:8px;padding:6px var(--gut);background:var(--surface);border-bottom:1px solid var(--line)}
.vt{white-space:nowrap;overflow:hidden;text-overflow:ellipsis;min-width:0}
.vf{flex:1;width:100%;border:0;background:#fff}
/* phân trang */
.pager{display:flex;align-items:center;gap:10px;flex-wrap:wrap;margin-top:14px}.pager select{width:auto;min-height:34px;padding:4px 8px}.pg{display:flex;gap:4px;flex-wrap:wrap}

/* điểm danh + bán trú */
.lich{display:flex;flex-wrap:wrap;gap:8px;align-items:center;margin-bottom:10px}
.lich .seg{display:flex;border:1px solid var(--line);border-radius:var(--r-s);overflow:hidden}.lich .seg button{border:0;border-radius:0;background:var(--surface);padding:7px 14px;min-height:36px}.lich .seg button.on{background:var(--pri);color:#fff}
.gw{contain:layout;overflow:auto;border:1px solid var(--line);border-radius:var(--r-s);background:var(--surface);max-height:68vh}
.gw,.gt,.lich{font-family:"Inter Bang",Inter,"Segoe UI",system-ui,-apple-system,Roboto,Arial,sans-serif;font-variant-numeric:tabular-nums;letter-spacing:.005em}
.gt{border-collapse:separate;border-spacing:0;font-size:.84rem;font-weight:400;width:max-content;min-width:100%}
.gt th,.gt td{border-right:1px solid var(--line);border-bottom:1px solid var(--line);padding:3px 4px;text-align:center;white-space:nowrap}
.gt thead th{font-weight:500;position:sticky;top:0;background:var(--surface2);z-index:2}
.gt .c1,.gt .c2{position:sticky;background:var(--surface);z-index:1;text-align:left}.gt thead .c1,.gt thead .c2{z-index:3;background:var(--surface2)}.gt .c1{left:0;min-width:34px;text-align:center}.gt .c2{left:34px;min-width:150px;box-shadow:2px 0 0 var(--line)}
.gt .sat{background:var(--sat-bg)!important;color:var(--sat-fg)}.gt .sun{background:var(--sun-bg)!important;color:var(--sun-fg)}.gt .hol{background:var(--hol-bg)!important;color:var(--mute)}
.gt tfoot td{position:sticky;bottom:0;background:var(--surface2);font-weight:500}
.gt .ab{display:block;width:100%;min-width:24px;min-height:22px;padding:0 2px;border:0;border-radius:4px;background:transparent;font-weight:500;color:inherit;cursor:pointer;line-height:1.3}
.gt .ab.x{color:var(--ok)}.gt .ab.p{color:var(--acc);background:var(--acc-t)}.gt .ab.k{color:var(--bad);background:var(--bad-t)}.gt .ab:hover{outline:1px solid var(--pri)}
.gt td.m0{color:var(--bad);font-weight:500}.gt td.mx{color:var(--ok);font-weight:500}.gt .ov{text-decoration:underline dotted}
.abig{min-width:64px;min-height:38px;border-radius:var(--r-s);border:1px solid var(--line);background:var(--surface);font-weight:500;font-size:1rem;cursor:pointer}.abig.x{background:var(--ok-t);color:var(--ok);border-color:var(--ok)}.abig.p{background:var(--acc-t);color:var(--acc);border-color:var(--acc)}.abig.k{background:var(--bad-t);color:var(--bad);border-color:var(--bad)}
.gt small{font-weight:300;opacity:.85}.gt .c2{font-weight:400}.lich b{font-weight:500}.lich .seg button{font-weight:400}.lich .seg button.on{font-weight:500}
.gt b,.gt th b{font-weight:500}

/* nút 3D trên thanh làm bài: nổi khối, lún xuống khi bấm */
.b3d{background:var(--pri);border:0;color:#fff;font-weight:700;border-radius:14px;box-shadow:0 4px 0 var(--pri-d);transform:translateY(0);transition:transform .08s,box-shadow .08s;white-space:nowrap}
.b3d:hover{background:var(--pri)}
.b3d:active{transform:translateY(4px);box-shadow:0 0 0 var(--pri-d)}
.b3d .ar{display:inline-flex;align-items:center;justify-content:center;width:24px;height:24px;border-radius:50%;background:rgba(255,255,255,.25);font-size:16px;line-height:1}
.b3d.sm{min-height:36px;padding:6px 12px}
.b3d.red{background:#e5484d;box-shadow:0 4px 0 #b3282d}.b3d.red:hover{background:#e5484d}.b3d.red:active{box-shadow:0 0 0 #b3282d}
.vbar{padding-bottom:10px}
@media(max-width:560px){.vbar .vfl{display:none}.vbar{gap:6px}}

/* Kho bài: 3 kiểu xem (Thẻ / Gọn / Lưới) */
.vm{display:inline-flex;border:1px solid var(--line);border-radius:999px;overflow:hidden;background:var(--surface);flex:none}
.vm button{border:0;background:transparent;color:var(--fg);padding:8px 13px;font-weight:600;cursor:pointer;min-height:40px}
.vm button.on{background:var(--pri);color:#fff}
#list.v-list{grid-template-columns:1fr;gap:8px}
#list.v-list .ex{flex-direction:row;align-items:center;flex-wrap:wrap;min-height:0;padding:8px 12px;gap:8px 12px}
#list.v-list .ex .hd{flex:1 1 220px;min-width:0;align-items:center}
#list.v-list .ex .ico{width:34px;height:34px;font-size:1.1rem;border-radius:10px}
#list.v-list .ex h3{font-size:.95rem}
#list.v-list .ex .hd .mute{display:none}
#list.v-list .ex .meta{flex:0 1 auto}
#list.v-list .ex .meta .chip:nth-child(n+3):not(.acc){display:none}
#list.v-list .ex .act{margin:0;flex:0 0 auto}
#list.v-grid{grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:10px}
#list.v-grid .ex{min-height:0;padding:10px;align-items:center;text-align:center}
#list.v-grid .ex .hd{flex-direction:column;align-items:center;gap:6px}
#list.v-grid .ex .hd .mute,#list.v-grid .ex .meta .chip:nth-child(n+2):not(.acc):not(.ok){display:none}
#list.v-grid .ex .meta{justify-content:center}
#list.v-grid .ex h3{font-size:.9rem}
#list.v-grid .ex .act{justify-content:center}
#list.v-grid .ex .act .btn.sm{padding:6px 9px;min-height:34px}
/* v2.1.8: nhận xét theo lượt làm */
.blh{border-top:1px dashed var(--line);padding:10px 0;display:grid;gap:6px}.blh textarea{width:100%}
.nxc{display:inline-flex;gap:4px;align-items:center;text-decoration:none;border-radius:999px;padding:3px 10px;font-weight:700;font-size:.85rem;background:var(--surface2);color:var(--mute)}
.nxc.has{background:var(--ok-t);color:var(--ok)}

/* v2.1.12: bộ nút thống nhất — xô rác đỏ (xóa), bút xanh (sửa), nút lùi/tiến một kiểu */
.del{--ic:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23000' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M3 6h18M8 6V4a1 1 0 0 1 1-1h6a1 1 0 0 1 1 1v2M6 6l1 14a1 1 0 0 0 1 1h8a1 1 0 0 0 1-1l1-14M10 11v6M14 11v6'/%3E%3C/svg%3E")}
.edit{--ic:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23000' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M4 20h4L19 9a2.8 2.8 0 0 0-4-4L4 16v4zM14 6l4 4'/%3E%3C/svg%3E")}
.ib,.mi{--sz:1.2em}
.ib::before,.mi::before{content:"";display:inline-block;flex:none;width:var(--sz);height:var(--sz);background:currentColor;-webkit-mask:var(--ic) center/contain no-repeat;mask:var(--ic) center/contain no-repeat}
.ib{display:inline-flex;align-items:center;justify-content:center;width:38px;height:38px;padding:0;border-radius:10px;border:1px solid transparent;background:transparent;cursor:pointer;font-size:1rem;flex:none;transition:background .12s,transform .1s}
.ib::before{--sz:21px}
.ib.del{color:var(--bad)}.ib.del:hover{background:var(--bad-t)}
.ib.edit{color:var(--info)}.ib.edit:hover{background:var(--info-t)}
.ib:active{transform:scale(.92)}
.ib:focus-visible,.back:focus-visible{outline:2px solid var(--pri);outline-offset:2px}
.btn.mi.del{color:var(--bad)}.btn.mi.edit{color:var(--info)}
.back{position:relative;display:inline-flex;align-items:center;gap:8px;min-height:38px;padding:5px 16px 5px 42px;border-radius:999px;border:1px solid color-mix(in srgb,var(--pri) 35%,var(--line));background:linear-gradient(180deg,var(--surface),var(--pri-t));color:var(--pri-d);font-weight:800;font-size:.92rem;text-decoration:none;cursor:pointer;box-shadow:0 2px 0 color-mix(in srgb,var(--pri) 45%,transparent);transition:transform .12s,box-shadow .12s;font-family:inherit}
.back::before{content:"";position:absolute;left:5px;top:50%;width:28px;height:28px;margin-top:-14px;border-radius:50%;background:var(--pri)}
.back::after{content:"";position:absolute;left:5px;top:50%;width:28px;height:28px;margin-top:-14px;background:#fff;-webkit-mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23000' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M14 6l-6 6 6 6'/%3E%3C/svg%3E") center/70% no-repeat;mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23000' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M14 6l-6 6 6 6'/%3E%3C/svg%3E") center/70% no-repeat}
.back.fwd{padding:5px 42px 5px 16px}.back.fwd::before,.back.fwd::after{left:auto;right:5px}.back.fwd::after{transform:scaleX(-1)}
.back:hover{transform:translateY(-1px);box-shadow:0 3px 0 color-mix(in srgb,var(--pri) 45%,transparent)}
.back:active{transform:translateY(1px);box-shadow:none}
.back[disabled]{opacity:.45;cursor:not-allowed;transform:none}
.page-h .back{margin-bottom:6px}
.dupn{color:var(--mute);font-weight:700;white-space:nowrap}
.dnav{display:flex;justify-content:space-between;align-items:center;gap:8px;margin:-4px 0 12px}
.btn.bad.solid{background:var(--bad);border-color:var(--bad);color:var(--bg)}.btn.bad.solid:hover{filter:brightness(1.08);background:var(--bad)}
.dlg .row.end{justify-content:flex-end;margin-top:12px}
#dAsk .row.end{margin-top:14px}
tr.clk{cursor:pointer}tr.clk:hover,tr.clk:focus-visible{background:var(--pri-t);outline:none}
/* v2.1.15: thanh tab gọn, có nút cuộn khi chật; menu tài khoản */
.tabs{position:relative;scroll-behavior:smooth;scrollbar-width:thin;scrollbar-color:var(--line) transparent;padding-bottom:0}
.tabs::-webkit-scrollbar{height:6px}.tabs::-webkit-scrollbar-thumb{background:var(--line);border-radius:6px}
.tabs button{padding:8px 11px;font-size:.92rem}
.tabs button:focus-visible{outline:2px solid var(--pri);outline-offset:-2px}
.tabw{position:relative;margin-bottom:14px}.tabw .tabs{margin-bottom:0}
.tabw .tbn{position:absolute;top:0;bottom:1px;width:34px;border:0;cursor:pointer;display:none;align-items:center;justify-content:center;font-size:1.3rem;font-weight:800;color:var(--pri-d);z-index:2}
.tabw .tbn.l{left:0;background:linear-gradient(90deg,var(--bg) 55%,transparent)}.tabw .tbn.r{right:0;background:linear-gradient(270deg,var(--bg) 55%,transparent)}
.tabw.cl .tbn.l{display:flex}.tabw.cr .tbn.r{display:flex}
.umenu{position:fixed;z-index:60;min-width:250px;background:var(--surface);border:1px solid var(--line);border-radius:12px;box-shadow:0 12px 34px rgba(0,0,0,.25);padding:6px;display:flex;flex-direction:column;gap:2px}
.umenu .umh{padding:8px 10px;font-weight:800;border-bottom:1px solid var(--line);margin-bottom:4px}.umenu small{display:block;color:var(--mute);font-weight:500;font-size:.78rem}
.umenu a{display:grid;grid-template-columns:28px 1fr;align-items:center;column-gap:6px;padding:8px 10px;border-radius:8px;color:var(--fg);text-decoration:none;font-weight:700}
.umenu a i{font-style:normal;grid-row:span 2;font-size:1.2rem;text-align:center}.umenu a:hover,.umenu a:focus-visible{background:var(--pri-t)}
.unm{max-width:190px}.unm span{overflow:hidden;text-overflow:ellipsis;white-space:nowrap;max-width:150px;display:inline-block;vertical-align:bottom}
.tabw .tbn{top:50%;bottom:auto;width:30px;height:30px;margin-top:-17px;border-radius:50%;background:var(--surface)!important;border:1px solid var(--line);box-shadow:0 2px 8px rgba(0,0,0,.18);font-size:1.15rem;line-height:1;padding:0}
.tabw .tbn.l{left:2px}.tabw .tbn.r{right:2px}
/* v2.1.17: nút hướng dẫn (!) và liên kết ở chân trang, chung một dòng */
.foot{display:flex;flex-wrap:wrap;align-items:center;gap:10px}
.foot .ni{flex:none;width:30px;height:30px;border-radius:50%;border:0;background:var(--pri);color:#fff;font-weight:800;font-size:1rem;cursor:pointer;display:inline-flex;align-items:center;justify-content:center}
.foot .fnote{color:var(--mute);font-size:.95rem}
.foot .fnote a{color:var(--info);font-weight:700}
.foot .grow{flex:1}
#xS:empty{display:none}
/* v2.3.0: nút khóa nhỏ, cùng cỡ với nút khác; nút bị khóa mờ đi */
.btn.dim{opacity:.55}.btn .lk{font-size:.62em;line-height:1;margin-right:2px}
/* v2.4.0: con mắt hiện/ẩn mật khẩu, liên kết chữ */
.pw{position:relative;display:block}.pw input{width:100%;padding-right:42px}
.pwb{position:absolute;right:4px;top:50%;transform:translateY(-50%);border:0;background:transparent;cursor:pointer;font-size:1.05rem;padding:6px 8px;line-height:1;border-radius:8px}.pwb:hover,.pwb:focus-visible{background:var(--line,#e5e7eb)}
a.lk{color:var(--pri,#0f766e);font-weight:600;text-decoration:underline;cursor:pointer}
.chip.mkR{background:#fee2e2;color:#b91c1c;border-color:#fca5a5;font-weight:700}.chip.mkP{background:#ede9fe;color:#6d28d9;border-color:#c4b5fd;font-weight:700}
@media (prefers-color-scheme:dark){:root:not([data-theme="light"]) .chip.mkR{background:#450a0a;color:#fecaca;border-color:#7f1d1d}:root:not([data-theme="light"]) .chip.mkP{background:#2e1065;color:#ddd6fe;border-color:#5b21b6}}
:root[data-theme="dark"] .chip.mkR{background:#450a0a;color:#fecaca;border-color:#7f1d1d}:root[data-theme="dark"] .chip.mkP{background:#2e1065;color:#ddd6fe;border-color:#5b21b6}
.curS{margin:0 10px;align-self:center;font-size:1rem;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;max-width:38vw}