:root{--bg:#f5f7fb;--panel:#fff;--text:#172033;--muted:#667085;--primary:#2563eb;--primary-soft:#eff6ff;--border:#e4e7ec;--answer:#067647;--answer-soft:#ecfdf3;--shadow:0 10px 30px rgba(16,24,40,.06)}*{box-sizing:border-box}html{-webkit-text-size-adjust:100%}body{margin:0;min-height:100vh;color:var(--text);background:var(--bg);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",Arial,sans-serif}button,input,select{font:inherit}button{cursor:pointer}.hidden{display:none!important}.topbar{position:sticky;top:0;z-index:30;color:#fff;background:linear-gradient(135deg,#1d4ed8,#2563eb 55%,#3b82f6);box-shadow:0 4px 18px rgba(37,99,235,.18)}.topbar-inner{width:min(1180px,calc(100% - 32px));min-height:104px;margin:auto;padding:20px 0;display:flex;align-items:center;justify-content:space-between;gap:20px}h1{margin:0;font-size:28px}.topbar p{margin:7px 0 0;opacity:.86;font-size:14px}.container{width:min(1180px,calc(100% - 32px));margin:20px auto 48px}.panel{background:var(--panel);border:1px solid var(--border);border-radius:18px;box-shadow:var(--shadow)}.button{height:42px;padding:0 17px;border:0;border-radius:11px;font-weight:650}.button.ghost{color:#fff;background:rgba(255,255,255,.14);border:1px solid rgba(255,255,255,.3)}.button.primary{color:#fff;background:var(--primary)}.upload-panel{padding:16px;margin-bottom:18px}.drop-zone{min-height:205px;border:2px dashed #bfd1fb;border-radius:15px;background:#f8fbff;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;padding:24px;transition:.2s;outline:none}.drop-zone:hover,.drop-zone:focus,.drop-zone.dragover{border-color:var(--primary);background:var(--primary-soft)}.upload-icon{width:50px;height:50px;border-radius:15px;display:grid;place-items:center;color:#fff;background:var(--primary);font-size:28px;font-weight:700;margin-bottom:12px}.drop-zone h2{margin:0;font-size:20px}.drop-zone p{margin:8px 0;color:var(--muted)}.drop-zone span{color:#98a2b3;font-size:13px}.template-note{margin-top:12px;color:var(--muted);font-size:13px;line-height:1.8}.template-note a{margin-left:10px;color:var(--primary);font-weight:650;text-decoration:none}.text-button{float:right;border:0;background:none;color:var(--primary);font-weight:650}.workspace{display:grid;grid-template-columns:245px minmax(0,1fr);gap:18px;align-items:start}.bank-panel{position:sticky;top:124px;overflow:hidden}.bank-panel-head{padding:16px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--border)}.bank-panel-head strong{display:block}.bank-panel-head span{display:block;margin-top:3px;color:var(--muted);font-size:12px}.icon-button{width:34px;height:34px;border:0;border-radius:10px;color:var(--primary);background:var(--primary-soft);font-size:21px}.bank-list{padding:8px;max-height:calc(100vh - 205px);overflow:auto}.bank-item{display:flex;align-items:center;gap:5px;border-radius:12px;margin-bottom:4px}.bank-item.active{background:var(--primary-soft)}.bank-select{min-width:0;flex:1;padding:11px;border:0;background:none;text-align:left}.bank-select strong,.bank-select span{display:block;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.bank-select strong{font-size:14px}.bank-select span{margin-top:4px;color:var(--muted);font-size:11px}.bank-delete{flex:0 0 auto;width:29px;height:29px;margin-right:6px;border:0;border-radius:50%;color:#98a2b3;background:transparent;font-size:18px}.bank-delete:hover{color:#b42318;background:#fef3f2}.content-area{min-width:0}.search-panel{padding:17px;margin-bottom:16px;position:sticky;top:124px;z-index:10}.search-row{display:grid;grid-template-columns:minmax(0,1fr) 145px;gap:11px}.search-box{position:relative}.search-box input{width:100%;height:50px;border:1px solid var(--border);border-radius:13px;padding:0 46px 0 44px;outline:none}.search-box input:focus,select:focus{border-color:#84adff;box-shadow:0 0 0 4px rgba(37,99,235,.1)}.search-icon{position:absolute;left:16px;top:50%;transform:translateY(-50%);color:#98a2b3;font-size:22px}.input-clear{position:absolute;right:10px;top:50%;width:30px;height:30px;transform:translateY(-50%);border:0;border-radius:50%;background:#f2f4f7;font-size:20px}select{height:50px;padding:0 13px;border:1px solid var(--border);border-radius:13px;background:#fff;outline:none}.summary-row{margin-top:11px;display:flex;justify-content:space-between;gap:12px;color:var(--muted);font-size:13px}.result-summary{color:var(--primary);font-weight:650}.results{display:grid;gap:13px}.question-card{overflow:hidden;background:#fff;border:1px solid var(--border);border-radius:16px;box-shadow:0 5px 18px rgba(16,24,40,.04)}.question-main{padding:18px 20px}.question-head{display:flex;align-items:flex-start;gap:10px;margin-bottom:13px}.number{flex:0 0 auto;min-width:30px;height:30px;border-radius:9px;display:grid;place-items:center;color:#fff;background:var(--primary);font-size:13px;font-weight:700}.badge{flex:0 0 auto;margin-top:3px;padding:4px 8px;border-radius:999px;background:#f2f4f7;font-size:12px}.question-text{flex:1;min-width:0;font-size:16px;font-weight:650;line-height:1.75;white-space:pre-wrap;word-break:break-word}.options{display:grid;gap:8px;margin-left:40px}.option{padding:10px 12px;border-radius:10px;background:#f8fafc;line-height:1.6;white-space:pre-wrap}.option-label{font-weight:700;margin-right:7px}.answer-block{border-top:1px solid #d1fadf;background:var(--answer-soft);padding:14px 20px}.answer-title{margin-bottom:6px;color:var(--answer);font-size:13px;font-weight:700}.answer-content{color:#085d3a;line-height:1.7;white-space:pre-wrap}.explanation{border-top:1px solid var(--border);padding:14px 20px;background:#fcfcfd;color:#475467;line-height:1.7;white-space:pre-wrap}.explanation strong{display:block;margin-bottom:5px}mark{padding:0 2px;background:#fef08a;border-radius:3px}.empty-state,.first-use{min-height:330px;display:grid;place-items:center;align-content:center;text-align:center;color:var(--muted);padding:30px}.empty-icon,.first-icon{font-size:50px;margin-bottom:8px}.empty-icon{color:#b8c4d8}.empty-state h2,.first-use h2{margin:0 0 8px;color:#344054;font-size:20px}.empty-state p,.first-use p{margin:0 0 18px;font-size:14px}.message{margin-top:12px;padding:12px 14px;border-radius:11px;font-size:14px}.message.error{color:#b42318;background:#fef3f2}footer{padding:20px 16px 34px;color:#98a2b3;text-align:center;font-size:12px}@media(max-width:760px){.topbar-inner{width:calc(100% - 24px);min-height:90px;padding:14px 0}h1{font-size:22px}.topbar p{font-size:12px}.topbar .button{height:38px;padding:0 12px}.container{width:calc(100% - 20px);margin-top:11px}.upload-panel{padding:11px}.workspace{display:block}.bank-panel{position:relative;top:auto;margin-bottom:11px}.bank-list{display:flex;gap:7px;overflow-x:auto;max-height:none;padding:8px}.bank-item{flex:0 0 180px;margin:0;border:1px solid var(--border)}.bank-panel-head{padding:11px 13px}.search-panel{top:101px;padding:11px;margin-bottom:11px}.search-row{grid-template-columns:1fr;gap:8px}.summary-row{flex-direction:column;gap:4px}.question-main{padding:15px 14px}.question-text{font-size:15px}.options{margin-left:0}.answer-block,.explanation{padding:13px 14px}.first-use{min-height:300px}}