:root{--ink:#172554;--ink-2:#334155;--muted:#64748b;--line:#e2e8f0;--bg:#f5f7fb;--card:#fff;--blue:#3157d5;--blue-light:#e8edff;--teal:#0d9488;--green:#16a34a;--red:#dc3545;--amber:#d97706;--shadow:0 9px 30px rgba(23,37,84,.08);font-family:"Noto Sans SC","Microsoft YaHei",system-ui,-apple-system,sans-serif}
.toast{position:fixed;z-index:100;top:82px;left:50%;transform:translate(-50%,-10px);opacity:0;pointer-events:none;background:#172554;color:#fff;padding:11px 17px;border-radius:8px;font-size:13px;box-shadow:0 8px 25px #17255444;transition:.22s}.toast.show{transform:translate(-50%,0);opacity:1}.toast.error{background:#be123c}
*{box-sizing:border-box}body{margin:0;color:var(--ink-2);background:var(--bg);min-height:100vh}.topbar{height:70px;background:#fff;border-bottom:1px solid var(--line);display:flex;align-items:center;padding:0 clamp(18px,5vw,76px);gap:44px;position:sticky;top:0;z-index:20}.brand{display:flex;align-items:center;gap:10px;cursor:pointer;color:var(--ink);white-space:nowrap}.brand-mark{width:34px;height:34px;border-radius:10px;background:linear-gradient(135deg,#4f68e4,#1c398f);display:grid;place-items:center;color:#fff;font-weight:800;font-size:21px;box-shadow:0 4px 10px #3157d544}.brand b{font-size:18px;letter-spacing:1px;display:block;line-height:1.1}.brand small{display:block;color:var(--muted);font-size:10px;letter-spacing:1px;margin-top:3px}.topnav{display:flex;align-items:center;gap:6px;height:100%}.nav-btn{height:100%;padding:0 14px;border:0;border-bottom:3px solid transparent;background:none;color:var(--muted);font-size:14px;cursor:pointer}.nav-btn:hover,.nav-btn.active{color:var(--blue);border-bottom-color:var(--blue);font-weight:600}.top-meta{margin-left:auto;color:var(--muted);font-size:12px;display:flex;gap:8px;align-items:center}.online-dot{width:8px;height:8px;background:#22c55e;border-radius:50%;display:inline-block;box-shadow:0 0 0 3px #dcfce7}.page{max-width:1180px;margin:0 auto;padding:34px 24px 60px;min-height:calc(100vh - 116px)}.footer{text-align:center;color:#94a3b8;font-size:12px;padding:18px}.footer span{padding:0 6px}.hero{display:flex;justify-content:space-between;align-items:flex-end;margin-bottom:28px}.eyebrow{color:var(--blue);font-size:12px;font-weight:700;letter-spacing:1px;margin:0 0 8px}.hero h1{font-size:32px;line-height:1.2;margin:0;color:var(--ink);letter-spacing:-.8px}.hero p{color:var(--muted);margin:10px 0 0;font-size:14px}.hero-actions{display:flex;gap:10px}.btn{border:0;border-radius:8px;padding:11px 18px;font-size:14px;font-weight:600;cursor:pointer;transition:.18s;display:inline-flex;align-items:center;justify-content:center;gap:7px}.btn:disabled{opacity:.45;cursor:not-allowed}.btn-primary{background:var(--blue);color:#fff;box-shadow:0 4px 10px #3157d533}.btn-primary:hover{background:#2447bd;transform:translateY(-1px)}.btn-light{background:#fff;color:var(--ink-2);border:1px solid var(--line)}.btn-light:hover{border-color:#b8c6eb;color:var(--blue);background:#fafbff}.btn-danger{background:#fff1f2;color:#be123c;border:1px solid #fecdd3}.btn-ghost{background:transparent;color:var(--blue);padding:8px 10px}.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin-bottom:28px}.stat-card{background:var(--card);border:1px solid var(--line);border-radius:13px;padding:19px 20px;box-shadow:var(--shadow)}.stat-card .label{font-size:12px;color:var(--muted);display:flex;justify-content:space-between}.stat-card .value{font-size:30px;font-weight:700;color:var(--ink);margin-top:8px}.stat-card .hint{font-size:11px;color:var(--muted);margin-top:4px}.stat-icon{font-size:18px;color:var(--blue);background:var(--blue-light);width:32px;height:32px;border-radius:8px;display:grid;place-items:center}.grid-2{display:grid;grid-template-columns:1.15fr .85fr;gap:20px}.panel{background:var(--card);border:1px solid var(--line);border-radius:13px;box-shadow:var(--shadow);padding:22px}.panel-head{display:flex;align-items:center;justify-content:space-between;margin-bottom:16px}.panel h2{font-size:17px;color:var(--ink);margin:0}.panel-sub{font-size:12px;color:var(--muted)}.mode-cards{display:grid;grid-template-columns:repeat(2,1fr);gap:14px}.mode-card{padding:20px;border:1px solid var(--line);border-radius:11px;position:relative;overflow:hidden;cursor:pointer;transition:.18s;background:#fff}.mode-card:hover{border-color:#a4b4ed;box-shadow:0 7px 20px #3157d51c;transform:translateY(-2px)}.mode-card .mode-icon{font-size:24px;width:43px;height:43px;border-radius:11px;display:grid;place-items:center;margin-bottom:14px}.mode-card.exam .mode-icon{background:#eef2ff;color:#4338ca}.mode-card.practice .mode-icon{background:#ecfdf5;color:#047857}.mode-card.wrong-mode .mode-icon{background:#fff7ed;color:#c2410c}.mode-card h3{font-size:16px;color:var(--ink);margin:0 0 6px}.mode-card p{font-size:12px;color:var(--muted);line-height:1.6;margin:0 0 16px}.mode-card .arrow{position:absolute;right:17px;bottom:18px;color:var(--blue);font-size:18px}.activity-list{display:flex;flex-direction:column;gap:3px}.activity{display:flex;align-items:center;padding:12px 10px;border-bottom:1px solid #f1f5f9;gap:12px}.activity:last-child{border:0}.activity-mark{width:33px;height:33px;border-radius:9px;background:var(--blue-light);color:var(--blue);display:grid;place-items:center;font-size:14px}.activity-main{flex:1;min-width:0}.activity-main b{display:block;color:var(--ink-2);font-size:13px}.activity-main small{color:var(--muted);font-size:11px}.activity-score{font-weight:700;color:var(--ink);font-size:14px}.empty{padding:28px 15px;text-align:center;color:#94a3b8;font-size:13px}.continue-banner{background:linear-gradient(110deg,#172554,#3157d5);color:#fff;border-radius:13px;padding:18px 22px;display:flex;align-items:center;margin-bottom:20px;gap:16px;box-shadow:0 8px 22px #1725542e}.continue-banner .continue-copy{flex:1}.continue-banner h3{margin:0 0 5px;font-size:15px}.continue-banner p{margin:0;opacity:.75;font-size:12px}.continue-banner .btn{background:#fff;color:var(--ink)}
/* quiz */.quiz-shell{max-width:1180px;margin:0 auto}.quiz-head{display:flex;align-items:center;gap:16px;margin-bottom:17px}.back-btn{border:0;background:none;color:var(--muted);font-size:13px;cursor:pointer;padding:4px 0}.back-btn:hover{color:var(--blue)}.quiz-title{font-size:20px;color:var(--ink);font-weight:700}.quiz-head .spacer{flex:1}.timer{display:flex;align-items:center;gap:6px;color:var(--ink);font-weight:600;font-size:14px;background:#fff;border:1px solid var(--line);border-radius:8px;padding:8px 12px}.timer.warn{color:var(--red);border-color:#fecaca;background:#fff7f7}.progress-wrap{height:6px;background:#e6eaf3;border-radius:10px;margin-bottom:22px;overflow:hidden}.progress-bar{height:100%;background:linear-gradient(90deg,#5572ea,#3157d5);border-radius:10px;transition:width .3s}.quiz-grid{display:grid;grid-template-columns:minmax(0,1fr) 270px;gap:19px;align-items:start}.question-card{background:#fff;border:1px solid var(--line);border-radius:13px;padding:28px 30px;box-shadow:var(--shadow);min-height:520px}.question-meta{display:flex;align-items:center;justify-content:space-between;margin-bottom:20px;color:var(--muted);font-size:12px}.question-no{color:var(--blue);font-size:13px;font-weight:700}.question-type{padding:4px 8px;background:#f1f5f9;border-radius:5px}.stem{font-size:18px;line-height:1.7;font-weight:600;color:var(--ink);margin:0 0 24px;white-space:pre-wrap}.options{display:flex;flex-direction:column;gap:11px}.option{display:flex;align-items:flex-start;gap:11px;border:1px solid var(--line);border-radius:9px;padding:14px 15px;cursor:pointer;transition:.16s;background:#fff;font-size:14px;line-height:1.6}.option:hover{border-color:#a8b8ee;background:#fafbff}.option.selected{border-color:#5871dd;background:#f0f3ff;color:#1e3a8a}.option.correct{border-color:#86efac;background:#f0fdf4;color:#166534}.option.incorrect{border-color:#fda4af;background:#fff1f2;color:#9f1239}.option input{position:absolute;opacity:0;pointer-events:none}.option-key{width:25px;height:25px;border:1px solid #cbd5e1;border-radius:50%;display:grid;place-items:center;font-size:12px;color:var(--muted);flex:none;margin-top:1px}.option.selected .option-key{border-color:var(--blue);background:var(--blue);color:#fff}.option.correct .option-key{border-color:var(--green);background:var(--green);color:#fff}.option.incorrect .option-key{border-color:var(--red);background:var(--red);color:#fff}.feedback{margin-top:18px;border-radius:9px;padding:13px 15px;font-size:13px;line-height:1.6}.feedback.ok{background:#f0fdf4;color:#166534;border:1px solid #bbf7d0}.feedback.bad{background:#fff1f2;color:#9f1239;border:1px solid #fecdd3}.feedback strong{font-weight:700}.quiz-actions{display:flex;justify-content:space-between;align-items:center;margin-top:25px}.quiz-actions .right{display:flex;gap:9px}.sheet{background:#fff;border:1px solid var(--line);border-radius:13px;padding:20px;box-shadow:var(--shadow);position:sticky;top:90px}.sheet h3{font-size:15px;color:var(--ink);margin:0}.sheet-progress{font-size:12px;color:var(--muted);margin:7px 0 15px}.sheet-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:7px}.sheet-btn{height:32px;border-radius:6px;border:1px solid var(--line);background:#fff;color:var(--muted);font-size:11px;cursor:pointer}.sheet-btn:hover{border-color:#9dafec}.sheet-btn.current{border:2px solid var(--blue);color:var(--blue);font-weight:700}.sheet-btn.answered{background:var(--blue);color:#fff;border-color:var(--blue)}.sheet-btn.answered.current{box-shadow:0 0 0 2px #b8c6ff}.sheet-legend{border-top:1px solid #f1f5f9;margin-top:17px;padding-top:13px;display:flex;flex-wrap:wrap;gap:10px 13px;color:var(--muted);font-size:10px}.legend-dot{width:10px;height:10px;border-radius:3px;display:inline-block;vertical-align:-1px;margin-right:4px;border:1px solid var(--line)}.legend-dot.blue{background:var(--blue)}.legend-dot.white{background:#fff}.legend-dot.outline{background:#fff;border:2px solid var(--blue)}
/* result/wrong */.result-card{max-width:680px;margin:20px auto;background:#fff;border:1px solid var(--line);border-radius:15px;padding:35px;box-shadow:var(--shadow);text-align:center}.result-badge{width:76px;height:76px;border-radius:50%;display:grid;place-items:center;background:#ecfdf5;color:var(--green);font-size:34px;margin:0 auto 14px}.result-card h1{margin:0;color:var(--ink);font-size:24px}.result-card p{color:var(--muted);font-size:13px;margin:8px 0 22px}.score-big{font-size:54px;font-weight:800;color:var(--blue);line-height:1}.score-big small{font-size:17px;color:var(--muted);font-weight:500}.result-stats{display:flex;justify-content:center;gap:44px;margin:24px 0;padding:19px 0;border-top:1px solid #f1f5f9;border-bottom:1px solid #f1f5f9}.result-stats b{display:block;color:var(--ink);font-size:22px}.result-stats span{font-size:11px;color:var(--muted)}.result-actions{display:flex;justify-content:center;gap:10px}.review-list{margin-top:25px;text-align:left;display:flex;flex-direction:column;gap:10px}.review-item{border:1px solid var(--line);border-radius:9px;padding:15px}.review-item-head{display:flex;justify-content:space-between;gap:10px;font-size:12px;margin-bottom:8px}.review-item-head b{color:var(--ink)}.review-item-head span{font-weight:700}.review-item-head .ok{color:var(--green)}.review-item-head .bad{color:var(--red)}.review-item-stem{font-size:13px;line-height:1.6;color:var(--ink-2)}.wrong-layout{display:grid;grid-template-columns:1fr 290px;gap:18px}.wrong-list{display:flex;flex-direction:column;gap:12px}.wrong-item{background:#fff;border:1px solid var(--line);border-radius:12px;padding:19px 21px;box-shadow:0 4px 15px rgba(23,37,84,.04)}.wrong-item-head{display:flex;gap:10px;align-items:center;margin-bottom:10px}.wrong-index{color:var(--blue);font-size:12px;font-weight:700}.wrong-count{font-size:11px;background:#fff1f2;color:#be123c;padding:3px 7px;border-radius:5px}.wrong-item .stem{font-size:15px;margin-bottom:13px}.wrong-answer{background:#f0fdf4;border:1px solid #bbf7d0;border-radius:7px;padding:9px 11px;color:#166534;font-size:12px}.wrong-item-actions{display:flex;justify-content:flex-end;margin-top:12px}.wrong-side{background:linear-gradient(160deg,#172554,#243d93);color:#fff;border-radius:13px;padding:24px;align-self:start;position:sticky;top:90px}.wrong-side h3{margin:0 0 10px;font-size:17px}.wrong-side p{font-size:12px;line-height:1.7;opacity:.76;margin:0 0 20px}.wrong-number{font-size:42px;font-weight:800}.wrong-number small{font-size:13px;font-weight:500;opacity:.75}.wrong-empty{background:#fff;border:1px solid var(--line);border-radius:13px;padding:60px 20px;text-align:center;color:var(--muted)}.wrong-empty .empty-icon{font-size:46px;opacity:.5;margin-bottom:11px}.loading{padding:80px;text-align:center;color:var(--muted)}.spinner{width:24px;height:24px;border:3px solid #dbe3fa;border-top-color:var(--blue);border-radius:50%;animation:spin .8s linear infinite;margin:0 auto 12px}@keyframes spin{to{transform:rotate(360deg)}}
@media(max-width:850px){.topbar{gap:20px;padding:0 18px}.topnav{gap:0}.nav-btn{padding:0 8px;font-size:12px}.top-meta{display:none}.page{padding:25px 16px 45px}.stats{grid-template-columns:repeat(2,1fr)}.grid-2,.wrong-layout{grid-template-columns:1fr}.sheet{position:static;order:-1}.quiz-grid{grid-template-columns:1fr}.quiz-head{gap:9px}.quiz-title{font-size:16px}.question-card{padding:22px 18px;min-height:0}.stem{font-size:16px}.hero{align-items:flex-start;gap:15px;flex-direction:column}.hero h1{font-size:26px}.mode-cards{grid-template-columns:1fr}.wrong-side{position:static}}
@media(max-width:500px){.topbar{height:62px}.brand small{display:none}.brand b{font-size:16px}.topnav{margin-left:auto}.nav-btn{font-size:11px;padding:0 5px}.stats{gap:9px}.stat-card{padding:14px}.stat-card .value{font-size:25px}.panel{padding:16px}.result-card{padding:27px 18px}.result-stats{gap:25px}.quiz-actions{flex-wrap:wrap;gap:11px}.quiz-actions .right{margin-left:auto}.sheet-grid{grid-template-columns:repeat(10,1fr)}}
.sheet-submit{width:100%;margin-top:16px}.review-options{font-size:13px;line-height:1.6}.review-correct{color:#15803d;font-weight:600}.review-answer{padding:10px;background:#f1f5f9;border-radius:7px;font-size:12px;line-height:1.7}.option:focus-within{outline:2px solid #3157d5;outline-offset:3px}.review-item-stem,.stem,.option{overflow-wrap:anywhere}.feedback .btn{margin-left:8px}.question-card{scroll-margin-top:85px}
@media(max-width:850px){.sheet{order:0}.quiz-head{flex-wrap:wrap}.timer{font-size:12px}.question-card{scroll-margin-top:75px}}
.bank-bar{display:flex;align-items:center;gap:18px;background:#fff;border:1px solid var(--line);border-radius:12px;padding:17px 20px;margin-bottom:22px}.bank-bar label{display:block;font-size:13px;font-weight:700;color:var(--ink)}.bank-bar p{font-size:11px;color:var(--muted);margin:5px 0 0}.bank-bar select{flex:1;min-width:0;padding:11px 14px;border:1px solid #cbd5e1;border-radius:8px;background:#f8fafc;color:var(--ink);font-family:inherit;font-size:13px}.bank-note{padding:12px 16px;background:#fffbeb;border:1px solid #fde68a;color:#92400e;border-radius:8px;font-size:13px;margin:0 0 22px;line-height:1.7}.mode-card.mode-disabled{opacity:.6;cursor:default;background:#f8fafc}.mode-card.mode-disabled:hover{transform:none;box-shadow:none;border-color:var(--line)}.upload-grid{display:grid;grid-template-columns:1.2fr 1fr;gap:22px;align-items:start}.upload-drop{border:2px dashed #b5c4f0;background:#f7f9ff;border-radius:12px;display:flex;align-items:center;flex-direction:column;padding:35px 22px;gap:15px;cursor:pointer;text-align:center}.upload-drop:hover{border-color:var(--blue);background:#f0f3ff}.upload-symbol{width:58px;height:58px;border-radius:15px;background:#e0e7ff;color:var(--blue);display:grid;place-items:center;font-size:32px;font-weight:700}.upload-drop strong{font-size:18px;color:var(--ink)}.upload-drop span:not(.upload-symbol){font-size:12px;color:var(--muted);overflow-wrap:anywhere;max-width:100%}.upload-drop small{font-size:11px;color:var(--muted)}.upload-drop input{max-width:100%;font-family:inherit;font-size:12px;color:var(--muted)}.upload-drop input::file-selector-button{padding:9px 14px;border:1px solid #aebfe9;border-radius:6px;color:var(--blue);background:#fff;font-family:inherit;cursor:pointer;margin-right:10px}.upload-submit{width:100%;margin-top:18px}.upload-help p{font-size:13px;line-height:1.8;color:var(--muted)}.upload-help pre{font-family:inherit;font-size:12px;line-height:1.8;background:#f1f5f9;padding:14px;border-radius:8px;white-space:pre-wrap}.upload-status{display:flex;align-items:center;gap:9px;color:var(--muted);font-size:12px;padding-top:12px}.upload-status .spinner{margin:0;width:17px;height:17px;border-width:2px}.hero-actions{flex-wrap:wrap}.stat-card .hint{overflow-wrap:anywhere}.feedback[hidden]{display:none}
@media(max-width:850px){.topbar{gap:12px}.upload-grid{grid-template-columns:1fr}.bank-bar{flex-wrap:wrap;gap:12px}.bank-bar>div{width:100%}.bank-bar select{flex-basis:60%}.hero-actions{width:100%}.upload-drop{padding:28px 15px}}
@media(max-width:500px){.topbar{padding:0 10px;gap:8px}.brand-mark{width:28px;height:28px;font-size:17px}.brand{gap:5px}.brand b{font-size:13px}.topnav .nav-btn{font-size:10px;padding:0 4px;white-space:nowrap}.bank-bar select{width:100%;flex-basis:100%}.bank-bar .btn{width:100%}.hero-actions .btn{padding:10px 13px;font-size:12px}.upload-help pre{font-size:11px}}