:root{--teal: #1f86a8;--teal-dark: #176c89;--teal-banner: #2a8fb0;--teal-soft: #e8f1f4;--header-text: #2c7fa0;--blue: #2f9fd6;--blue-dark: #2585bd;--blue-deep: #1a57b0;--orange: #f2a51e;--orange-dark: #d98e0c;--green: #2e9e5b;--red: #d24b4b;--ink: #2a3942;--muted: #6b7d86;--line: #cfdde2;--page-bg: #d9e6ea;--frame-bg: #ffffff;--content-bg: #eef3f5;--radius: 6px;--shadow: 0 2px 10px rgba(20, 60, 80, .12)}*{box-sizing:border-box}html,body,#root{height:100%}body{margin:0;font-family:Segoe UI,Roboto,Helvetica Neue,Arial,sans-serif;color:var(--ink);background:var(--page-bg);-webkit-font-smoothing:antialiased;line-height:1.45}a{color:var(--teal-dark);text-decoration:none}a:hover{text-decoration:underline}.app-shell{min-height:100%;display:flex;flex-direction:column;align-items:center;padding:14px}.app-frame{width:100%;max-width:1080px;background:var(--frame-bg);border:1px solid var(--teal);border-radius:4px;overflow:hidden;box-shadow:var(--shadow);display:flex;flex-direction:column;flex:1}.topbar{text-align:center;font-size:12.5px;color:#1d5b73;letter-spacing:.3px;padding:4px 0;background:#f3f8fa;border-bottom:1px solid #e3eef1}.org-header{display:flex;align-items:center;gap:16px;padding:12px 20px;background:#fff}.org-logo{width:52px;height:52px;flex:0 0 52px;border-radius:50%;display:grid;place-items:center;background:radial-gradient(circle at 50% 40%,#fff,#eef3f5);border:1px solid #e1e9ec}.org-logo svg{width:46px;height:46px}.brand-logo{flex:0 0 auto;display:block;height:56px;width:auto}.org-text{line-height:1.3}.org-text .l1{color:var(--header-text);font-size:19px;font-weight:600}.org-text .l2,.org-text .l3{color:var(--header-text);font-size:16px}.banner{background:linear-gradient(180deg,var(--teal-banner),var(--teal));color:#fff;padding:9px 20px;font-size:15px;font-weight:500;letter-spacing:.2px}.content{background:var(--content-bg);padding:22px;flex:1}.footer{background:linear-gradient(180deg,var(--teal),var(--teal-dark));color:#eaf6fa;text-align:center;padding:18px 16px 16px;line-height:1.5}.footer-prepared{display:flex;flex-direction:column;gap:1px}.footer-label{font-size:10.5px;text-transform:uppercase;letter-spacing:.1em;opacity:.8}.footer-name{font-size:16px;font-weight:700;color:#fff;letter-spacing:.2px}.footer-email{font-size:12.5px;color:#cdeaf2;word-break:break-word}.footer-email:hover{color:#fff}.footer-socials{display:flex;justify-content:center;gap:9px;margin:12px 0;flex-wrap:wrap}.footer-social{width:34px;height:34px;border-radius:50%;display:grid;place-items:center;background:#ffffff24;color:#fff;transition:background .15s,transform .15s}.footer-social:hover{background:#ffffff52;transform:translateY(-2px);text-decoration:none}.footer-social svg{width:18px;height:18px;display:block}.footer-tagline{font-size:12.5px;opacity:.92;border-top:1px solid rgba(255,255,255,.22);padding-top:11px;margin-top:2px;font-weight:500;letter-spacing:.2px}.btn{-webkit-appearance:none;-moz-appearance:none;appearance:none;border:0;cursor:pointer;color:#fff;font-size:14px;font-weight:500;padding:8px 18px;border-radius:var(--radius);transition:filter .15s,transform .02s;box-shadow:0 1px 2px #0000002e}.btn:hover{filter:brightness(1.06)}.btn:active{transform:translateY(1px)}.btn:disabled{opacity:.55;cursor:not-allowed;filter:none}.btn-blue{background:linear-gradient(180deg,var(--blue),var(--blue-dark))}.btn-orange{background:linear-gradient(180deg,var(--orange),var(--orange-dark))}.btn-deep{background:linear-gradient(180deg,#2a6fd0,var(--blue-deep))}.btn-green{background:linear-gradient(180deg,#37b06a,var(--green))}.btn-ghost{background:#fff;color:var(--teal-dark);border:1px solid var(--teal);box-shadow:none}.btn-sm{padding:5px 12px;font-size:13px}.btn-lg{padding:11px 30px;font-size:16px}.btn-block{display:block;width:100%}.panel{background:#fff;border:1px solid var(--line);border-radius:var(--radius)}.card{background:#fff;border:1px solid var(--line);border-radius:8px;padding:16px;box-shadow:0 1px 4px #1e50640f}.section-title{font-size:17px;font-weight:600;color:var(--ink);margin:0 0 12px}.muted{color:var(--muted)}.center{text-align:center}.login-wrap{display:grid;place-items:center;padding:24px 8px}.login-card{width:100%;max-width:440px;background:#fff;border:1px solid var(--line);border-radius:8px;padding:22px 24px 26px;box-shadow:var(--shadow)}.login-card h2{margin:0 0 16px;font-size:18px;color:var(--ink);font-weight:600}.field{margin-bottom:12px}.field label{display:block;font-size:12.5px;color:var(--muted);margin-bottom:4px}.input{width:100%;padding:10px 12px;border:1px solid var(--teal);border-radius:var(--radius);font-size:14px;outline:none;background:#fff}.input:focus{box-shadow:0 0 0 3px #1f86a826}.btn-row{display:flex;gap:10px;margin-top:6px}.google-btn{display:inline-flex;align-items:center;justify-content:center;gap:10px;width:100%;padding:11px 16px;border:1px solid #dadce0;border-radius:var(--radius);background:#fff;color:#3c4043;font-size:14.5px;font-weight:600;cursor:pointer;box-shadow:0 1px 2px #00000014;transition:background .15s,box-shadow .15s}.google-btn:hover{background:#f7f9fb;box-shadow:0 1px 4px #00000024}.google-btn:disabled{opacity:.6;cursor:not-allowed}.divider{display:flex;align-items:center;gap:10px;color:var(--muted);font-size:12px;margin:16px 0}.divider:before,.divider:after{content:"";height:1px;background:var(--line);flex:1}.instructions{background:#fff;border:1px solid var(--line);border-radius:8px;padding:22px 24px 24px;box-shadow:0 1px 4px #1e50640f}.welcome-banner{background:linear-gradient(180deg,var(--teal-banner),var(--teal));color:#fff;border-radius:var(--radius);padding:16px 22px;margin-bottom:22px;box-shadow:0 2px 8px #143c5029}.welcome-title{margin:0 0 3px;font-size:26px;font-weight:600;color:#fff;line-height:1.15}.welcome-sub{margin:0;font-size:14px;opacity:.92}.notice-heading{color:var(--header-text);font-weight:700;font-size:17px;margin:0 0 12px}.notice-list{margin:0 0 18px;padding-left:22px}.notice-list li{margin-bottom:11px;color:var(--ink)}.exam-ready{color:var(--green);font-weight:600;margin:0 0 14px}.notice-actions{display:flex;justify-content:flex-end}.instructions .em{color:var(--orange-dark);font-weight:600}.exam-grid{display:grid;grid-template-columns:1fr 280px;gap:18px;align-items:start}.exam-main{background:#fff;border:1px solid var(--line);border-radius:6px;padding:16px 18px;min-height:60vh}.exam-side{position:sticky;top:14px}.exam-panel{background:linear-gradient(180deg,var(--teal-banner),var(--teal));color:#fff;border-radius:8px;padding:14px;box-shadow:var(--shadow)}.exam-panel .row{display:flex;gap:12px;align-items:center}.exam-panel .avatar{width:64px;height:64px;border-radius:6px;object-fit:cover;border:2px solid rgba(255,255,255,.6);background:#cfe6ee}.exam-panel .who{font-weight:700;font-size:15px}.exam-panel .timer{font-size:20px;font-weight:800;margin:8px 0 2px;font-variant-numeric:tabular-nums}.exam-panel .timer.warn{color:#ffd9a8}.exam-panel .timer.danger{color:#ffd2d2;animation:pulse 1s infinite}@keyframes pulse{50%{opacity:.6}}.exam-panel .answered{font-size:13.5px;opacity:.95}.exam-panel .panel-link{color:#eaffff;font-size:13px;text-decoration:underline;cursor:pointer;margin-top:8px;display:inline-block}.exam-panel .progress{height:8px;background:#ffffff40;border-radius:5px;margin-top:10px;overflow:hidden}.exam-panel .progress>span{display:block;height:100%;background:#d6f3ff}.pager{display:flex;align-items:center;justify-content:space-between;gap:10px;margin:2px 0 12px;flex-wrap:wrap}.pager-bottom{margin-top:18px;border-top:1px solid var(--line);padding-top:14px}.pager-info{font-size:13px;color:var(--muted)}.pager-info b{color:var(--ink)}.pager-nums{display:flex;flex-wrap:wrap;gap:6px;margin-bottom:14px}.pager-num{min-width:30px;height:30px;padding:0 8px;border:1px solid var(--line);background:#fff;color:var(--teal-dark);border-radius:6px;cursor:pointer;font-size:13px;font-weight:600}.pager-num:hover{border-color:var(--teal);background:var(--teal-soft)}.pager-num.active{background:var(--teal);color:#fff;border-color:var(--teal)}.unanswered-panel{background:#fff8ec;border:1px solid #f1d491;border-radius:8px;padding:12px 14px;margin-bottom:14px}.unanswered-panel .up-head{display:flex;justify-content:space-between;align-items:center;margin-bottom:8px}.up-grid{display:flex;flex-wrap:wrap;gap:6px}.up-chip{min-width:30px;height:30px;padding:0 6px;border:1px solid var(--orange);background:#fff;color:var(--orange-dark);border-radius:6px;cursor:pointer;font-size:13px;font-weight:600}.up-chip:hover{background:var(--orange);color:#fff}.passage{background:#fbfdfe;border:1px solid var(--line);border-left:4px solid var(--orange);padding:12px 14px;border-radius:4px;margin-bottom:14px;white-space:pre-wrap;font-size:14px}.passage .ptitle{font-weight:700;color:var(--orange-dark);margin-bottom:6px}.q{padding:12px 4px;border-bottom:1px dashed #e4ebee}.q:last-child{border-bottom:0}.q.flagged{background:#fff8ec;border-radius:6px}.q-head{display:flex;gap:8px;align-items:baseline}.q-no{font-weight:700;color:var(--ink);min-width:26px}.q-text{font-size:15px;overflow-wrap:break-word}.mathtext{font-variant-numeric:tabular-nums}sup,sub{font-size:.72em;line-height:0;position:relative;vertical-align:baseline}sup{top:-.55em}sub{bottom:-.25em}.sqrt{display:inline-flex;align-items:flex-start;white-space:nowrap}.sqrt:before{content:"√";margin-right:1px;line-height:1.05}.sqrt .radicand{border-top:1.5px solid currentColor;padding:1px 2px 0}.frac{display:inline-flex;flex-direction:column;vertical-align:middle;text-align:center;margin:0 .12em}.frac-n{padding:0 .35em;border-bottom:1.3px solid currentColor;line-height:1.25}.frac-d{padding:0 .35em;line-height:1.25}.matrix{display:inline-flex;align-items:stretch;vertical-align:middle;margin:0 .15em}.matrix:before,.matrix:after{content:"";width:5px;border:1.5px solid currentColor;flex:none}.matrix:before{border-right:0;margin-right:5px}.matrix:after{border-left:0;margin-left:5px}.matrix-grid{display:grid;gap:3px 16px;text-align:center;align-items:center;padding:2px 0}.matrix-cell{white-space:nowrap}.accent{position:relative;display:inline-block}.accent:after{position:absolute;left:-1px;right:-1px;text-align:center;line-height:1;pointer-events:none;font-weight:400}.accent-vec:after{content:"→";top:-.72em;font-size:.72em}.accent-vecleft:after{content:"←";top:-.72em;font-size:.72em}.accent-bar:after{content:"";top:-.02em;left:0;right:0;border-top:1.4px solid currentColor}.accent-hat:after{content:"^";top:-.6em;font-size:.9em}.accent-tilde:after{content:"~";top:-.66em;font-size:.85em}.accent-dot:after{content:"˙";top:-.62em;font-size:1em}.accent-ddot:after{content:"¨";top:-.68em;font-size:.85em}.q-meta{font-size:12px;color:var(--muted);margin:2px 0 8px 34px;display:flex;gap:10px;align-items:center}.flag-btn{background:none;border:0;cursor:pointer;color:var(--muted);font-size:12px}.flag-btn.on{color:var(--orange-dark);font-weight:600}.opts{list-style:none;margin:0;padding:0 0 0 34px}.opt{display:flex;align-items:flex-start;gap:10px;padding:7px 10px;border-radius:5px;cursor:pointer;border:1px solid transparent}.opt:hover{background:#f2f8fa}.opt input{margin-top:3px;accent-color:var(--teal)}.opt.selected{background:var(--teal-soft);border-color:var(--teal)}.opt .ltr{font-weight:600;color:var(--muted)}.opt>span:last-child{min-width:0;overflow-wrap:break-word}.opt.correct{background:#e7f7ee;border-color:var(--green)}.opt.wrong{background:#fdeced;border-color:var(--red)}.solution{margin:8px 0 2px 34px;padding:10px 12px;background:#f1f8fb;border-left:3px solid var(--teal);border-radius:0 6px 6px 0;font-size:13.5px;color:#2f4a55;line-height:1.6}.sol-tag{display:inline-block;font-size:11px;font-weight:700;text-transform:uppercase;letter-spacing:.05em;color:var(--teal-dark);margin-right:8px}.exam-actions{display:flex;gap:10px;align-items:center;margin-top:18px;flex-wrap:wrap}.go-top{position:fixed;right:22px;bottom:22px;z-index:30}.modal-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#0f283773;display:grid;place-items:center;z-index:50;padding:16px}.modal{background:#fff;border:1px solid #c4d4d9;border-radius:6px;padding:22px 24px;max-width:460px;width:100%;box-shadow:0 10px 40px #0000004d}.modal h3{margin:0 0 8px;font-size:17px}.modal p{margin:0 0 18px;color:#364853}.modal .modal-actions{display:flex;justify-content:flex-end;gap:10px}.dash-hero{background:linear-gradient(120deg,var(--teal-dark),var(--teal));color:#fff;border-radius:12px;padding:20px 22px;margin-bottom:18px;box-shadow:var(--shadow)}.dash-hero h2{margin:0 0 4px;font-size:22px;font-weight:700;color:#fff}.dash-hero p{margin:0;font-size:13.5px;opacity:.92}.dash-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:14px}.set-card{display:flex;flex-direction:column;gap:10px;position:relative;overflow:hidden;transition:transform .15s,box-shadow .15s,border-color .15s}.set-card:before{content:"";position:absolute;inset:0 0 auto 0;height:3px;background:linear-gradient(90deg,var(--teal),var(--blue))}.set-card:hover{transform:translateY(-3px);box-shadow:0 8px 20px #1e506426;border-color:var(--teal)}.set-card .sc-top{display:flex;justify-content:space-between;align-items:center}.set-card .sc-title{font-weight:700;font-size:16px;color:var(--ink)}.set-card .sc-meta{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--muted)}.set-card .sc-meta b{color:var(--teal-dark);font-weight:700}.set-card .sc-meta .sc-dot{width:3px;height:3px;border-radius:50%;background:var(--muted);opacity:.5}.set-card .sc-best{font-size:12px;font-weight:700;color:var(--green)}.set-card .sc-progress{height:6px;background:#eef3f5;border-radius:4px;overflow:hidden}.set-card .sc-progress>span{display:block;height:100%;background:linear-gradient(90deg,var(--teal),var(--green));border-radius:4px}.set-card .sc-progress.empty{background:#f1f5f7}.set-card .btn{margin-top:auto}.pill{font-size:11px;padding:2px 9px;border-radius:12px;background:var(--teal-soft);color:var(--teal-dark);font-weight:600}.pill.green{background:#e7f7ee;color:#1e7a45}.stat-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(140px,1fr));gap:12px}.stat{background:#fff;border:1px solid var(--line);border-radius:10px;padding:16px 14px;text-align:center;position:relative;overflow:hidden;transition:transform .15s,box-shadow .15s}.stat:before{content:"";position:absolute;inset:0 0 auto 0;height:3px;background:linear-gradient(90deg,var(--teal),var(--blue))}.stat:hover{transform:translateY(-2px);box-shadow:0 6px 16px #1e50641f}.stat .v{font-size:26px;font-weight:800;color:var(--teal-dark)}.stat .k{font-size:12px;color:var(--muted);margin-top:2px}.table{width:100%;border-collapse:collapse;font-size:13.5px}.table th,.table td{text-align:left;padding:8px 10px;border-bottom:1px solid var(--line)}.table th{color:var(--muted);font-weight:600;background:#f6f9fa}.table tr:hover td{background:#f9fcfd}.bar{height:8px;background:#eef3f5;border-radius:5px;overflow:hidden;min-width:80px}.bar>span{display:block;height:100%;background:linear-gradient(90deg,var(--teal),var(--blue))}.appbar{display:flex;align-items:center;justify-content:space-between;gap:12px}.appbar .nav{display:flex;gap:18px;align-items:center}.navlink{padding:6px 2px;font-size:13.5px;color:var(--teal-dark);cursor:pointer;border-bottom:2px solid transparent;transition:color .15s,border-color .15s}.navlink:hover{color:var(--teal)}.navlink.active{font-weight:600;border-bottom-color:var(--teal)}.user-chip{display:flex;align-items:center;gap:8px}.user-chip img{width:30px;height:30px;border-radius:50%}.avatar-letter{width:30px;height:30px;border-radius:50%;background:var(--teal-soft);color:var(--teal-dark);display:grid;place-items:center;font-weight:700;font-size:13px}.badge-result{font-size:40px;font-weight:800}.badge-result.pass{color:var(--green)}.badge-result.fail{color:var(--red)}.flash{padding:10px 14px;border-radius:6px;font-size:13.5px;margin-bottom:12px}.flash.err{background:#fdeced;color:#9b2c2c;border:1px solid #f3c5c5}.flash.ok{background:#e7f7ee;color:#1e7a45;border:1px solid #bfe6cd}.flash.info{background:var(--teal-soft);color:var(--teal-dark);border:1px solid #c5e0e8}.spinner{width:34px;height:34px;border:4px solid #d6e6eb;border-top-color:var(--teal);border-radius:50%;animation:spin .8s linear infinite}.spin-wrap{display:grid;place-items:center;padding:40px;gap:12px;color:var(--muted)}@keyframes spin{to{transform:rotate(360deg)}}@media (max-width: 820px){.exam-grid{grid-template-columns:1fr}.exam-side{position:static;order:-1}.org-text .l1{font-size:17px}}@media (max-width: 520px){.app-shell{padding:0}.app-frame{border-radius:0}.content{padding:14px}.opts{padding-left:10px}.q-meta{margin-left:0}}