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#000c;color:#111;position:relative;border-radius:2px}.kb-problem-grid{display:grid;gap:12px 24px}.kb-problem-grid.cols-2{grid-template-columns:repeat(2,1fr)}.kb-problem-grid.cols-3{grid-template-columns:repeat(3,1fr)}.kb-problem-grid.cols-4{grid-template-columns:repeat(4,1fr)}.kb-problem{display:flex;align-items:center;gap:8px;padding:12px 0}.kb-problem-index{font-size:13px;color:#999;min-width:24px}.kb-problem-exp{font-weight:600;color:#111;letter-spacing:.5px;flex:1}.kb-problem-answer{display:none}.kb-modal-worksheet .kb-modal-footer{padding:24px 30px;display:flex;justify-content:center;align-items:center;gap:16px;border-top:1px solid rgba(255,255,255,.08);background:#ffffff05}.modal-action-btn{min-width:140px;height:48px;padding:0 24px;display:flex;align-items:center;justify-content:center;font-size:15px;border-radius:12px}.kb-modal-close{-webkit-appearance:none;-moz-appearance:none;appearance:none;background:transparent;border:0;color:var(--kb-subtle);font-size:24px;cursor:pointer;padding:4px;line-height:1}.kb-modal-close:hover{color:#fff}.kb-modal-overlay{position:fixed;top:0;right:0;bottom:0;left:0;z-index:50;display:grid;place-items:center;padding:18px;background:#00000073;-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px)}.kb-modal{width:min(420px,92vw);border-radius:18px;border:1px solid rgba(255,255,255,.16);background:#141622b8;box-shadow:0 40px 90px #0009;padding:16px;animation:kbPop .16s ease-out}@keyframes kbPop{0%{transform:translateY(8px) scale(.98);opacity:0}to{transform:translateY(0) scale(1);opacity:1}}.kb-modal-title{font-weight:820;font-size:16px;text-align:center;margin-top:2px}.kb-modal-message{margin-top:10px;color:#ffffffb8;line-height:1.6;text-align:center}.kb-modal-footer{margin-top:14px;display:grid}.kb-modal-footer .kb-btn{border-radius:14px}@media print{@page{size:A4;margin:0}html,body{height:auto!important;margin:0!important;padding:0!important;background:#fff!important;color:#000!important;overflow:visible!important}#kb-starfield,.kb-header,.kb-hero,.kb-panel-controls,.kb-footnote,.kb-breadcrumbs,.kb-modal-header,.kb-modal-footer,.kb-modal-close,.kb-sidebar,#kb-astronaut-wrap,#kb-spaceship-wrap,#kb-rocket-wrap,#kb-planet,#kb-satellite-wrap,.kb-shooting-star{display:none!important}.kb-app,.kb-main{padding:0!important;margin:0!important;display:block!important;min-height:0!important}.kb-modal-overlay{position:static!important;background:none!important;-webkit-backdrop-filter:none!important;backdrop-filter:none!important;padding:0!important;display:block!important;width:100%!important;height:auto!important}.kb-modal-worksheet{position:static!important;width:100%!important;height:auto!important;max-width:none!important;background:none!important;border:0!important;box-shadow:none!important;display:block!important;border-radius:0!important}.kb-modal-body{padding:0!important;background:none!important;overflow:visible!important;display:block!important}.kb-sheet{width:210mm!important;min-height:297mm!important;margin:0!important;padding:20mm!important;box-shadow:none!important;border-radius:0!important;page-break-after:avoid;page-break-inside:avoid}}