:root{--ink-950: #0a0c10;--ink-900: #111318;--ink-800: #1c2027;--ink-700: #333a45;--ink-600: #4b5563;--ink-500: #6b7280;--ink-400: #9aa3af;--ink-300: #c7cdd6;--ink-200: #e3e6ec;--ink-150: #eceef3;--ink-100: #f3f4f7;--ink-50: #f8f9fb;--paper: #ffffff;--brand-700: #3f3ad6;--brand-600: #4f46e5;--brand-500: #6259f0;--brand-400: #8b83f6;--brand-100: #eceafe;--brand-50: #f6f5ff;--brand-gradient: linear-gradient(135deg, #6259f0 0%, #4f46e5 55%, #4338ca 100%);--success-600: #12805c;--success-500: #16a34a;--success-50: #ecfdf5;--warn-600: #b45309;--warn-500: #f59e0b;--warn-50: #fffbeb;--danger-600: #d33a3a;--danger-500: #ef4444;--danger-50: #fef2f2;--info-500: #0ea5e9;--info-50: #f0f9ff;--font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI Variable Text", "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", Inter, Roboto, sans-serif;--font-mono: ui-monospace, "SF Mono", "JetBrains Mono", "Cascadia Mono", Consolas, "Liberation Mono", monospace;--r-xs: 8px;--r-sm: 10px;--r-md: 14px;--r-lg: 18px;--r-xl: 24px;--r-full: 999px;--shadow-xs: 0 1px 2px rgba(16, 24, 40, .04);--shadow-sm: 0 2px 8px rgba(16, 24, 40, .05), 0 1px 2px rgba(16, 24, 40, .04);--shadow-md: 0 8px 24px rgba(16, 24, 40, .07), 0 2px 6px rgba(16, 24, 40, .04);--shadow-lg: 0 24px 60px rgba(16, 24, 40, .12), 0 6px 18px rgba(16, 24, 40, .06);--shadow-brand: 0 10px 30px rgba(79, 70, 229, .22);--ring: 0 0 0 4px rgba(98, 89, 240, .14);--ease: cubic-bezier(.22, .61, .36, 1);--header-h: 64px}@media (prefers-color-scheme: dark){:root{--ink-950: #f7f8fb;--ink-900: #eef0f6;--ink-800: #dfe3ec;--ink-700: #c3c9d6;--ink-600: #a4acbd;--ink-500: #8b93a5;--ink-400: #6d7488;--ink-300: #4a5163;--ink-200: #2c3140;--ink-150: #242936;--ink-100: #1c202b;--ink-50: #171a23;--paper: #12151d;--brand-100: #23214a;--brand-50: #1b1a33;--shadow-xs: 0 1px 2px rgba(0, 0, 0, .3);--shadow-sm: 0 2px 8px rgba(0, 0, 0, .35);--shadow-md: 0 10px 28px rgba(0, 0, 0, .42);--shadow-lg: 0 28px 70px rgba(0, 0, 0, .5);--success-50: #0d2a20;--danger-50: #2c1414;--warn-50: #2b2110;--info-50: #0c2230}}*{box-sizing:border-box}html,body,#root{height:100%}body{margin:0;font-family:var(--font-sans);background:var(--ink-50);color:var(--ink-900);font-size:15px;line-height:1.6;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;font-feature-settings:"tnum" on,"lnum" on;overflow-x:hidden}img,canvas,svg{max-width:100%}.x-card,.x-grow,.x-passage,.x-mono{overflow-wrap:anywhere}a{color:inherit;text-decoration:none}button{font-family:inherit}::selection{background:#6259f02e}::-webkit-scrollbar{width:10px;height:10px}::-webkit-scrollbar-thumb{background:var(--ink-200);border-radius:var(--r-full);border:3px solid transparent;background-clip:content-box}::-webkit-scrollbar-thumb:hover{background:var(--ink-300);background-clip:content-box}::-webkit-scrollbar-track{background:transparent}.x-container{width:100%;max-width:1120px;margin:0 auto;padding:0 24px;box-sizing:border-box}.x-narrow{max-width:680px}.x-wide{max-width:1320px}.x-page{min-height:100vh;display:flex;flex-direction:column}.x-main{flex:1;padding:32px 0 72px}.x-stack{display:flex;flex-direction:column;gap:16px}.x-row{display:flex;align-items:center;gap:12px}.x-row-between{display:flex;align-items:center;justify-content:space-between;gap:16px}.x-wrap{flex-wrap:wrap}.x-grow{flex:1;min-width:0}.x-center{display:flex;align-items:center;justify-content:center}.x-header{position:sticky;top:0;z-index:40;height:var(--header-h);background:color-mix(in srgb,var(--paper) 82%,transparent);backdrop-filter:saturate(180%) blur(20px);-webkit-backdrop-filter:saturate(180%) blur(20px);border-bottom:1px solid var(--ink-150)}.x-header-inner{height:var(--header-h);display:flex;align-items:center;gap:28px}.x-brand{display:flex;align-items:center;gap:10px;font-weight:650;letter-spacing:-.01em;color:var(--ink-900)}.x-brand-mark{width:32px;height:32px;border-radius:9px;background:var(--brand-gradient);color:#fff;display:grid;place-items:center;font-size:15px;font-weight:700;box-shadow:var(--shadow-brand);letter-spacing:0}.x-brand-text{display:flex;flex-direction:column;line-height:1.15}.x-brand-text small{font-size:10.5px;color:var(--ink-400);letter-spacing:.14em;text-transform:uppercase;font-weight:600}.x-nav{display:flex;align-items:center;gap:4px;flex:1}.x-nav-link{padding:7px 13px;border-radius:var(--r-sm);font-size:14px;font-weight:500;color:var(--ink-600);transition:background .16s var(--ease),color .16s var(--ease)}.x-nav-link:hover{background:var(--ink-100);color:var(--ink-900)}.x-nav-link.active{background:var(--brand-50);color:var(--brand-600)}.x-card{background:var(--paper);border:1px solid var(--ink-150);border-radius:var(--r-lg);box-shadow:var(--shadow-xs)}.x-card-pad{padding:24px}.x-card-head{padding:20px 24px;border-bottom:1px solid var(--ink-150);display:flex;align-items:center;justify-content:space-between;gap:16px}.x-card-title{font-size:15.5px;font-weight:620;letter-spacing:-.01em}.x-card-sub{font-size:13px;color:var(--ink-500);margin-top:2px}.x-hover-lift{transition:transform .2s var(--ease),box-shadow .2s var(--ease),border-color .2s var(--ease)}.x-hover-lift:hover{transform:translateY(-2px);box-shadow:var(--shadow-md);border-color:var(--ink-200)}.x-btn{--btn-bg: var(--paper);--btn-fg: var(--ink-800);--btn-border: var(--ink-200);display:inline-flex;align-items:center;justify-content:center;gap:7px;height:38px;padding:0 16px;border-radius:var(--r-sm);border:1px solid var(--btn-border);background:var(--btn-bg);color:var(--btn-fg);font-size:14px;font-weight:550;cursor:pointer;white-space:nowrap;transition:background .16s var(--ease),border-color .16s var(--ease),transform .12s var(--ease),box-shadow .16s var(--ease),opacity .16s var(--ease);-webkit-user-select:none;user-select:none}.x-btn:hover:not(:disabled){border-color:var(--ink-300);background:var(--ink-50)}.x-btn:active:not(:disabled){transform:scale(.985)}.x-btn:disabled{opacity:.5;cursor:not-allowed}.x-btn:focus-visible{outline:none;box-shadow:var(--ring)}.x-btn-primary{--btn-bg: var(--brand-600);--btn-fg: #fff;--btn-border: var(--brand-600);box-shadow:var(--shadow-brand)}.x-btn-primary:hover:not(:disabled){--btn-bg: var(--brand-700);--btn-border: var(--brand-700)}.x-btn-dark{--btn-bg: var(--ink-900);--btn-fg: var(--paper);--btn-border: var(--ink-900)}.x-btn-dark:hover:not(:disabled){--btn-bg: var(--ink-800);--btn-border: var(--ink-800)}.x-btn-ghost{--btn-bg: transparent;--btn-border: transparent;--btn-fg: var(--ink-600)}.x-btn-ghost:hover:not(:disabled){--btn-bg: var(--ink-100);--btn-border: transparent}.x-btn-danger{--btn-bg: var(--danger-500);--btn-fg: #fff;--btn-border: var(--danger-500)}.x-btn-danger:hover:not(:disabled){--btn-bg: var(--danger-600);--btn-border: var(--danger-600)}.x-btn-sm{height:32px;padding:0 12px;font-size:13px;border-radius:var(--r-xs)}.x-btn-lg{height:46px;padding:0 24px;font-size:15px;border-radius:var(--r-md)}.x-btn-block{width:100%}.x-field{display:flex;flex-direction:column;gap:7px}.x-label{font-size:13px;font-weight:560;color:var(--ink-700)}.x-label .req{color:var(--danger-500);margin-left:3px}.x-hint{font-size:12.5px;color:var(--ink-400)}.x-error{font-size:12.5px;color:var(--danger-600)}.x-input,.x-select,.x-textarea{width:100%;height:42px;padding:0 14px;border:1px solid var(--ink-200);border-radius:var(--r-sm);background:var(--paper);color:var(--ink-900);font-size:14.5px;font-family:inherit;transition:border-color .16s var(--ease),box-shadow .16s var(--ease),background .16s var(--ease)}.x-textarea{height:auto;min-height:92px;padding:11px 14px;line-height:1.6;resize:vertical}.x-input::placeholder,.x-textarea::placeholder{color:var(--ink-400)}.x-input:hover,.x-select:hover,.x-textarea:hover{border-color:var(--ink-300)}.x-input:focus,.x-select:focus,.x-textarea:focus{outline:none;border-color:var(--brand-500);box-shadow:var(--ring)}.x-input.invalid,.x-textarea.invalid{border-color:var(--danger-500)}.x-input.mono{font-family:var(--font-mono);letter-spacing:.08em}.x-select{-webkit-appearance:none;-moz-appearance:none;appearance:none;background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath d='M3 4.5 6 7.5 9 4.5' stroke='%236b7280' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");background-repeat:no-repeat;background-position:right 12px center;padding-right:34px}.x-input-group{display:flex;gap:10px}.x-switch{position:relative;width:42px;height:24px;border-radius:var(--r-full);border:none;background:var(--ink-200);cursor:pointer;transition:background .2s var(--ease);flex:none}.x-switch:after{content:"";position:absolute;top:2px;left:2px;width:20px;height:20px;border-radius:50%;background:#fff;box-shadow:var(--shadow-xs);transition:transform .2s var(--ease)}.x-switch.on{background:var(--brand-600)}.x-switch.on:after{transform:translate(18px)}.x-badge{display:inline-flex;align-items:center;gap:5px;height:22px;padding:0 9px;border-radius:var(--r-full);font-size:12px;font-weight:560;background:var(--ink-100);color:var(--ink-600);white-space:nowrap}.x-badge-brand{background:var(--brand-50);color:var(--brand-600)}.x-badge-success{background:var(--success-50);color:var(--success-600)}.x-badge-warn{background:var(--warn-50);color:var(--warn-600)}.x-badge-danger{background:var(--danger-50);color:var(--danger-600)}.x-badge-outline{background:transparent;border:1px solid var(--ink-200)}.x-dot{width:6px;height:6px;border-radius:50%;background:currentColor;flex:none}.x-tabs{display:inline-flex;gap:4px;padding:4px;background:var(--ink-100);border-radius:var(--r-md)}.x-tab{padding:7px 16px;border-radius:var(--r-sm);border:none;background:transparent;font-size:13.5px;font-weight:550;color:var(--ink-500);cursor:pointer;transition:all .16s var(--ease)}.x-tab:hover{color:var(--ink-800)}.x-tab.active{background:var(--paper);color:var(--ink-900);box-shadow:var(--shadow-xs)}.x-avatar{border-radius:var(--r-full);background:var(--brand-gradient);color:#fff;display:grid;place-items:center;font-weight:600;overflow:hidden;flex:none;-webkit-user-select:none;user-select:none}.x-avatar img{width:100%;height:100%;object-fit:cover}.x-menu{position:absolute;right:0;top:calc(100% + 8px);min-width:220px;background:var(--paper);border:1px solid var(--ink-150);border-radius:var(--r-md);box-shadow:var(--shadow-lg);padding:6px;z-index:60;animation:x-pop .16s var(--ease)}.x-menu-item{display:flex;align-items:center;gap:10px;width:100%;padding:9px 11px;border:none;background:transparent;border-radius:var(--r-xs);font-size:14px;color:var(--ink-700);cursor:pointer;text-align:left}.x-menu-item:hover{background:var(--ink-100);color:var(--ink-900)}.x-menu-item.danger{color:var(--danger-600)}.x-menu-sep{height:1px;background:var(--ink-150);margin:5px 4px}.x-menu-head{padding:10px 11px 12px;border-bottom:1px solid var(--ink-150);margin-bottom:5px}@keyframes x-pop{0%{opacity:0;transform:translateY(-4px) scale(.98)}to{opacity:1;transform:none}}.x-table-wrap{overflow-x:auto;border-radius:var(--r-lg)}.x-table{width:100%;border-collapse:collapse;font-size:13.5px}.x-table th{text-align:left;font-weight:560;color:var(--ink-500);font-size:12.5px;padding:12px 16px;background:var(--ink-50);border-bottom:1px solid var(--ink-150);white-space:nowrap}.x-table td{padding:13px 16px;border-bottom:1px solid var(--ink-150);vertical-align:middle}.x-table tr:last-child td{border-bottom:none}.x-table tbody tr{transition:background .14s var(--ease)}.x-table tbody tr:hover{background:var(--ink-50)}.x-mono{font-family:var(--font-mono);font-size:13px;letter-spacing:.04em}.x-muted{color:var(--ink-500)}.x-dim{color:var(--ink-400)}.x-small{font-size:12.5px}.x-strong{font-weight:600}.x-h1{font-size:32px;font-weight:680;letter-spacing:-.022em;line-height:1.25;margin:0}.x-h2{font-size:22px;font-weight:640;letter-spacing:-.018em;margin:0}.x-h3{font-size:17px;font-weight:600;letter-spacing:-.012em;margin:0}.x-divider{height:1px;background:var(--ink-150);margin:20px 0}.x-empty{padding:56px 24px;text-align:center;color:var(--ink-400)}.x-empty-icon{width:52px;height:52px;margin:0 auto 14px;border-radius:var(--r-md);background:var(--ink-100);display:grid;place-items:center;color:var(--ink-400)}.x-grid{display:grid;gap:16px}.x-grid-2{grid-template-columns:repeat(2,minmax(0,1fr))}.x-grid-3{grid-template-columns:repeat(3,minmax(0,1fr))}.x-grid-4{grid-template-columns:repeat(4,minmax(0,1fr))}.x-grid-hero{grid-template-columns:minmax(0,1.05fr) minmax(0,.95fr);gap:56px;align-items:center}.x-grid-side{grid-template-columns:minmax(0,240px) minmax(0,1fr);gap:20px;align-items:start}.x-grid-main{grid-template-columns:minmax(0,1.5fr) minmax(0,1fr);gap:22px;align-items:start}@media (max-width: 1024px){.x-grid-hero{grid-template-columns:minmax(0,1fr);gap:36px}}@media (max-width: 900px){.x-grid-2,.x-grid-3,.x-grid-4{grid-template-columns:repeat(2,minmax(0,1fr))}.x-grid-side,.x-grid-main{grid-template-columns:minmax(0,1fr)}}@media (max-width: 640px){.x-grid-2,.x-grid-3,.x-grid-4{grid-template-columns:minmax(0,1fr)}.x-container{padding:0 16px}.x-h1{font-size:26px}.x-card-pad{padding:18px}.x-hide-sm{display:none!important}.x-stack-on-sm{flex-direction:column!important;align-items:stretch!important}.x-stack-on-sm>.x-btn{width:100%}.x-modal-head,.x-modal-body,.x-modal-foot{padding-left:18px;padding-right:18px}.x-menu{right:-6px;min-width:200px}.x-chart{gap:6px}}.x-skeleton{background:linear-gradient(90deg,var(--ink-100) 25%,var(--ink-150) 37%,var(--ink-100) 63%);background-size:400% 100%;animation:x-shimmer 1.4s ease infinite;border-radius:var(--r-xs)}@keyframes x-shimmer{0%{background-position:100% 50%}to{background-position:0 50%}}.x-spin{animation:x-rotate .9s linear infinite}@keyframes x-rotate{to{transform:rotate(360deg)}}.x-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#0a0c106b;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);display:grid;place-items:center;padding:24px;z-index:100;animation:x-fade .16s var(--ease)}.x-modal{width:100%;max-width:520px;max-height:88vh;overflow:auto;background:var(--paper);border-radius:var(--r-xl);box-shadow:var(--shadow-lg);animation:x-pop .2s var(--ease)}.x-modal-head{padding:22px 26px 4px}.x-modal-body{padding:18px 26px}.x-modal-foot{padding:8px 26px 24px;display:flex;justify-content:flex-end;gap:10px}@keyframes x-fade{0%{opacity:0}}.x-toasts{position:fixed;top:18px;left:50%;transform:translate(-50%);z-index:200;display:flex;flex-direction:column;gap:10px;align-items:center;pointer-events:none}.x-toast{display:flex;align-items:center;gap:10px;padding:11px 18px;background:var(--ink-900);color:var(--paper);border-radius:var(--r-full);font-size:14px;box-shadow:var(--shadow-lg);animation:x-toast-in .22s var(--ease);max-width:90vw}.x-toast.error{background:var(--danger-600);color:#fff}.x-toast.success{background:var(--success-600);color:#fff}@keyframes x-toast-in{0%{opacity:0;transform:translateY(-10px)}}.x-watermark-tag{display:inline-flex;align-items:center;gap:6px;font-size:11.5px;color:var(--ink-400);font-family:var(--font-mono)}.x-answer-chip{display:inline-flex;align-items:center;min-height:30px;padding:5px 12px;border-radius:var(--r-sm);background:var(--brand-50);border:1px solid var(--brand-100);color:var(--brand-700);font-weight:560;font-size:14.5px;line-height:1.5}.x-question{padding:18px 0;border-bottom:1px dashed var(--ink-150)}.x-question:last-child{border-bottom:none}.x-q-index{width:25px;height:25px;border-radius:8px;background:var(--ink-900);color:var(--paper);font-size:12px;font-weight:600;display:grid;place-items:center;flex:none;margin-top:1px}.x-option{display:flex;gap:10px;padding:7px 12px;border-radius:var(--r-xs);font-size:14px;color:var(--ink-600)}.x-option.correct{background:var(--success-50);color:var(--success-600);font-weight:550}.x-option-label{font-weight:600;flex:none;width:16px}.x-passage{padding:16px 18px;background:var(--ink-50);border-radius:var(--r-md);border:1px solid var(--ink-150);font-size:14.5px;line-height:1.85;color:var(--ink-700);white-space:pre-wrap;word-break:break-word}.x-steps{display:flex;gap:8px;align-items:center}.x-step{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--ink-400)}.x-step-dot{width:22px;height:22px;border-radius:50%;border:1px solid var(--ink-200);display:grid;place-items:center;font-size:11.5px;font-weight:600;background:var(--paper)}.x-step.active{color:var(--brand-600);font-weight:550}.x-step.active .x-step-dot{background:var(--brand-600);border-color:var(--brand-600);color:#fff}.x-step.done .x-step-dot{background:var(--success-50);border-color:var(--success-500);color:var(--success-600)}.x-drop{border:1.5px dashed var(--ink-200);border-radius:var(--r-md);padding:22px;text-align:center;transition:all .18s var(--ease);cursor:pointer;background:var(--ink-50)}.x-drop:hover{border-color:var(--brand-400);background:var(--brand-50)}.x-drop.filled{border-style:solid;border-color:var(--success-500);background:var(--success-50)}.x-preview-img{max-height:260px;border-radius:var(--r-md);box-shadow:var(--shadow-sm)}.x-link{color:var(--brand-600);font-weight:550;cursor:pointer}.x-link:hover{text-decoration:underline}.a-shell{display:flex;min-height:100vh;background:var(--ink-50)}.a-side{width:236px;flex:none;border-right:1px solid var(--ink-150);background:var(--paper);padding:18px 12px;position:sticky;top:0;height:100vh;overflow-y:auto}.a-side-brand{display:flex;align-items:center;gap:10px;padding:6px 10px 18px;border-bottom:1px solid var(--ink-150);margin-bottom:14px}.a-side-group{font-size:11px;font-weight:650;letter-spacing:.1em;text-transform:uppercase;color:var(--ink-400);padding:14px 12px 6px}.a-side-link{display:flex;align-items:center;gap:10px;padding:9px 12px;border-radius:var(--r-sm);font-size:14px;color:var(--ink-600);transition:all .15s var(--ease)}.a-side-link:hover{background:var(--ink-100);color:var(--ink-900)}.a-side-link.active{background:var(--brand-50);color:var(--brand-600);font-weight:560}.a-main{flex:1;min-width:0;padding:28px 32px 72px}.a-topbar{display:flex;align-items:center;justify-content:space-between;gap:16px;margin-bottom:24px}@media (max-width: 900px){.a-side{position:fixed;left:0;top:0;z-index:90;transform:translate(-100%);transition:transform .22s var(--ease);box-shadow:var(--shadow-lg)}.a-side.open{transform:none}.a-main{padding:18px 16px 64px}}.x-chart{display:flex;align-items:flex-end;gap:12px;height:180px;padding-top:12px}.x-chart-col{flex:1;display:flex;flex-direction:column;align-items:center;gap:8px;height:100%;justify-content:flex-end}.x-chart-stack{width:100%;max-width:40px;display:flex;flex-direction:column;justify-content:flex-end;gap:3px;flex:1}.x-chart-bar{border-radius:5px 5px 3px 3px;min-height:3px;transition:height .4s var(--ease)}.x-export-hidden{position:fixed;left:-10000px;top:0}