:root{--color-primary:#111;--color-primary-active:#242424;--color-primary-disabled:#e5e7eb;--color-ink:#111;--color-body:#374151;--color-muted:#6b7280;--color-muted-soft:#898989;--color-hairline:#e5e7eb;--color-hairline-soft:#f3f4f6;--color-canvas:#fff;--color-surface-soft:#f8f9fa;--color-surface-card:#f5f5f5;--color-surface-dark:#101010;--color-on-primary:#fff;--color-on-dark:#fff;--color-on-dark-soft:#a1a1aa;--color-success:#10b981;--color-error:#ef4444;--rounded-md:8px;--rounded-lg:12px;--rounded-xl:16px;--rounded-pill:9999px;--rounded-full:9999px;--arcoblue-6:var(--color-primary);--arcoblue-5:var(--color-primary-active);--color-bg-1:var(--color-canvas);--color-bg-2:var(--color-canvas);--color-bg-3:var(--color-surface-card);--color-bg-4:var(--color-surface-soft);--color-text-1:var(--color-ink);--color-text-2:var(--color-body);--color-text-3:var(--color-muted);--color-border:var(--color-hairline);--color-border-2:var(--color-hairline);--border-radius-small:var(--rounded-md);--border-radius-medium:var(--rounded-md);--border-radius-large:var(--rounded-lg);--font-family:"Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif}*{box-sizing:border-box;margin:0;padding:0}body{font-family:var(--font-family);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background:var(--color-canvas);color:var(--color-body);line-height:1.6}h1,h2,h3,h4,h5,h6,.arco-typography-title,.arco-typography>h1,.arco-typography>h2,.arco-typography>h3{font-family:var(--font-family);color:var(--color-ink)!important;letter-spacing:-.04em!important;font-weight:600!important}.arco-card{border-radius:var(--rounded-lg)!important;border-color:var(--color-hairline)!important;background-color:var(--color-canvas)!important;box-shadow:none!important;transition:transform .2s,box-shadow .2s!important}.arco-card-hoverable{transition:transform .2s,box-shadow .2s!important}.arco-btn{border-radius:var(--rounded-md)!important;font-weight:600!important}.arco-menu-light{background:0 0!important}.arco-menu-light .arco-menu-item.arco-menu-selected{font-weight:600;color:var(--color-primary)!important}.arco-menu-light .arco-menu-item{color:var(--color-muted);transition:color .2s}.arco-menu-light .arco-menu-item:hover{color:var(--color-primary)}.arco-layout-header{border-bottom:1px solid var(--color-hairline)!important}.arco-table-container{border-radius:var(--rounded-lg);border:1px solid var(--color-hairline)}.arco-table-th{background-color:var(--color-surface-soft)!important;color:var(--color-muted)!important;font-weight:600!important}.arco-table-td{border-bottom:1px solid var(--color-hairline)!important}.arco-select-view,.arco-input{border-radius:var(--rounded-md)!important;border-color:var(--color-hairline)!important}.arco-select-view:hover,.arco-input:hover{border-color:var(--color-primary-active)!important}.arco-tag{font-weight:500;border-radius:var(--rounded-pill)!important}.problem-markdown h1,.problem-markdown h2,.problem-markdown h3{margin:16px 0 8px;font-weight:600}.problem-markdown h2{border-bottom:1px solid var(--color-border);padding-bottom:6px;font-size:18px}.problem-markdown p{margin:8px 0;line-height:1.8}.problem-markdown pre{background:var(--color-fill-2);border-radius:4px;margin:8px 0;padding:12px 16px;font-size:14px;overflow-x:auto}.problem-markdown code{font-family:JetBrains Mono,Fira Code,Consolas,monospace;font-size:14px}.problem-markdown pre code{background:0 0;padding:0}.problem-markdown p>code{background:var(--color-fill-2);border-radius:3px;padding:2px 6px;font-size:13px}.problem-markdown ul,.problem-markdown ol{margin:8px 0;padding-left:24px}.problem-markdown li{margin:4px 0;line-height:1.6}.problem-markdown blockquote{border-left:3px solid var(--color-primary-6);color:var(--color-text-2);margin:8px 0;padding-left:12px}.problem-markdown table{border-collapse:collapse;width:100%;margin:12px 0;display:block;overflow-x:auto}.problem-markdown th,.problem-markdown td{border:1px solid var(--color-border);text-align:left;padding:8px 12px;font-size:14px}.problem-markdown th{background:var(--color-fill-2);font-weight:600}.problem-markdown tr:nth-child(2n){background:var(--color-fill-1)}.problem-markdown .katex-display{margin:12px 0;overflow-x:auto}@keyframes skeletonPulse{0%,to{opacity:1}50%{opacity:.4}}@keyframes borderBreathe{0%,to{border-color:var(--color-hairline)}50%{border-color:#d1d5db}}@keyframes fadeSlideUp{0%{opacity:0;transform:translateY(12px)scale(.995)}to{opacity:1;transform:translateY(0)scale(1)}}.page-transition-wrapper{will-change:opacity, transform;animation:.5s cubic-bezier(.16,1,.3,1) forwards fadeSlideUp}.arco-menu-horizontal .arco-menu-selected-label{background-color:var(--color-primary)!important;transition:left .5s cubic-bezier(.34,1.56,.64,1),width .5s cubic-bezier(.34,1.56,.64,1)!important}.difficulty-badge{white-space:nowrap;letter-spacing:0;border-radius:9999px;justify-content:center;align-items:center;padding:2px 10px;font-weight:500;line-height:1.6;transition:background .2s,color .2s;display:inline-flex;position:relative;overflow:hidden}@keyframes shimmerSweep{0%{left:-100%}20%{left:200%}to{left:200%}}.difficulty-badge[class*=difficulty-shimmer-]:after{content:"";background:linear-gradient(90deg,#fff0 0%,#ffffff4d 50%,#fff0 100%);width:50%;height:100%;animation:3s infinite shimmerSweep;position:absolute;top:0;left:-100%;transform:skew(-20deg)}.difficulty-shimmer-ice{color:#fff!important;background:#3b82f6!important}.difficulty-shimmer-purple{color:#fff!important;background:#8b5cf6!important}.difficulty-shimmer-pink{color:#fff!important;background:#ec4899!important}.difficulty-shimmer-legendary{color:#f59e0b!important;background:#111!important;border:1px solid #f59e0b4d!important}.difficulty-shimmer-legendary:after{background:linear-gradient(90deg,#f59e0b00 0%,#f59e0b33 50%,#f59e0b00 100%)!important}.footer{background:var(--color-surface-dark);color:var(--color-on-dark-soft);padding:80px 0 48px}.footer-grid{grid-template-columns:2fr repeat(4,1fr);gap:48px;margin-bottom:48px;display:grid}@media (width<=1024px){.footer-grid{grid-template-columns:repeat(2,1fr)}}@media (width<=768px){.footer-grid{grid-template-columns:1fr}}.footer-col h4{text-transform:uppercase;letter-spacing:.05em;margin-bottom:24px;font-size:14px;color:var(--color-on-dark)!important}.footer-links{list-style:none}.footer-links li{margin-bottom:12px}.footer-links a{color:var(--color-on-dark-soft);font-size:14px;text-decoration:none;transition:color .2s}.footer-links a:hover{color:var(--color-on-dark)}.footer-bottom{border-top:1px solid #222;justify-content:space-between;padding-top:32px;font-size:13px;display:flex}.nav-pill-group{background:var(--color-surface-soft);border-radius:var(--rounded-pill);gap:4px;padding:6px;display:inline-flex}.nav-pill{border-radius:var(--rounded-pill);color:var(--color-muted);cursor:pointer;background:0 0;border:none;padding:8px 16px;font-size:14px;font-weight:500;text-decoration:none;transition:all .2s}.nav-pill:hover{color:var(--color-ink)}.nav-pill.active{background:var(--color-canvas);color:var(--color-ink);box-shadow:0 1px 2px #0000000d}@keyframes aiTypingDots{0%,20%{content:""}40%{content:"."}60%{content:".."}80%,to{content:"..."}}.ai-typing-indicator:after{content:"";animation:1.5s infinite aiTypingDots}.ai-chat-message pre{border:1px solid var(--color-border);border-radius:8px;margin:8px 0;overflow:hidden}.ai-chat-message pre code{font-family:Consolas,monospace!important;font-size:14px!important}.ai-chat-message p>code,.ai-chat-message li>code{color:#e64553;background:#00000014;border-radius:4px;padding:2px 6px;font-family:Consolas,monospace;font-size:14px}.ai-think-block{border:1px solid var(--color-border);background:var(--color-fill-1);border-radius:8px;margin:6px 0;overflow:hidden}.ai-think-block[open]{margin-bottom:8px}.ai-think-summary{color:var(--color-text-3);cursor:pointer;-webkit-user-select:none;user-select:none;padding:6px 12px;font-size:12px;list-style:none}.ai-think-summary::-webkit-details-marker{display:none}.ai-think-summary:before{content:"▶";margin-right:6px;font-size:10px;transition:transform .2s;display:inline-block}.ai-think-block[open] .ai-think-summary:before{transform:rotate(90deg)}.ai-think-content{color:var(--color-text-2);white-space:pre-wrap;word-break:break-word;max-height:400px;padding:0 12px 8px;font-size:13px;line-height:1.6;overflow-y:auto}.ai-chat-scroll{scrollbar-width:none;-ms-overflow-style:none}.ai-chat-scroll::-webkit-scrollbar{display:none}
