:root{color-scheme:light;--rk-bg: #f7f9fc;--rk-bg-elevated: #ffffff;--rk-surface: #ffffff;--rk-surface-secondary: #f1f5fa;--rk-surface-tertiary: #e8eef6;--rk-overlay: rgb(14 27 45 / 45%);--rk-text: #0e1b2d;--rk-text-secondary: #55657c;--rk-text-muted: #7d8ca1;--rk-text-inverted: #ffffff;--rk-border: #dde5ef;--rk-border-strong: #c6d2e2;--rk-primary: #1668d8;--rk-primary-hover: #0f55b5;--rk-primary-soft: #e6f0fd;--rk-primary-contrast: #ffffff;--rk-accent: #0e9a94;--rk-accent-soft: #e2f6f5;--rk-success: #14804a;--rk-success-soft: #e4f5ec;--rk-warning: #a86400;--rk-warning-soft: #fdf1dd;--rk-danger: #c2334a;--rk-danger-soft: #fde9ec;--rk-code-bg: #101a2b;--rk-code-text: #e6edf7;--rk-code-inline-bg: #eef3f9;--rk-shadow-xs: 0 1px 2px rgb(14 27 45 / 6%);--rk-shadow-sm: 0 2px 8px rgb(14 27 45 / 6%);--rk-shadow-md: 0 10px 30px rgb(14 27 45 / 8%);--rk-shadow-lg: 0 24px 60px rgb(14 27 45 / 12%);--rk-ring: 0 0 0 3px color-mix(in srgb, var(--rk-primary) 22%, transparent);--rk-radius-sm: 6px;--rk-radius: 10px;--rk-radius-lg: 16px;--rk-radius-xl: 22px;--rk-radius-pill: 999px;--rk-container: 1180px;--rk-header-height: 66px;--rk-gutter: clamp(1rem, 4vw, 2rem);--rk-section-y: clamp(3.5rem, 7vw, 6.5rem);--rk-font: "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI", "PingFang SC", "Hiragino Sans", "Microsoft YaHei", sans-serif;--rk-font-mono: ui-monospace, "SFMono-Regular", "JetBrains Mono", Consolas, "Liberation Mono", monospace;--rk-transition: .16s cubic-bezier(.4, 0, .2, 1)}:root[data-theme=dark]{color-scheme:dark;--rk-bg: #0b1220;--rk-bg-elevated: #111a2b;--rk-surface: #121c2f;--rk-surface-secondary: #17233a;--rk-surface-tertiary: #1e2c46;--rk-overlay: rgb(3 7 14 / 65%);--rk-text: #eef4fc;--rk-text-secondary: #a7b6cc;--rk-text-muted: #7f8ea6;--rk-text-inverted: #0b1220;--rk-border: #24334d;--rk-border-strong: #33455f;--rk-primary: #62a8ff;--rk-primary-hover: #8cc0ff;--rk-primary-soft: #16273f;--rk-primary-contrast: #071122;--rk-accent: #3fd0c8;--rk-accent-soft: #102b2c;--rk-success: #4ec98a;--rk-success-soft: #10291e;--rk-warning: #e0a63f;--rk-warning-soft: #2c2312;--rk-danger: #f2708a;--rk-danger-soft: #2e1620;--rk-code-bg: #060c16;--rk-code-text: #dbe6f5;--rk-code-inline-bg: #1b2942;--rk-shadow-xs: 0 1px 2px rgb(0 0 0 / 40%);--rk-shadow-sm: 0 2px 10px rgb(0 0 0 / 40%);--rk-shadow-md: 0 14px 34px rgb(0 0 0 / 45%);--rk-shadow-lg: 0 28px 64px rgb(0 0 0 / 55%)}*,*:before,*:after{box-sizing:border-box}html{min-width:320px;scroll-behavior:smooth;background:var(--rk-bg);-webkit-text-size-adjust:100%}body{margin:0;background:var(--rk-bg);color:var(--rk-text);font-family:var(--rk-font);font-size:16px;line-height:1.65;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}img,svg{max-width:100%}h1,h2,h3,h4,h5,h6{margin:0;color:var(--rk-text);font-weight:750;line-height:1.15;letter-spacing:-.022em}h1{font-size:clamp(2.35rem,5vw,4rem);letter-spacing:-.035em}h2{font-size:clamp(1.65rem,3vw,2.4rem);letter-spacing:-.028em}h3{font-size:clamp(1.1rem,1.6vw,1.32rem)}p{margin:0 0 1rem}a{color:var(--rk-primary);text-decoration:none;transition:color var(--rk-transition)}a:hover{color:var(--rk-primary-hover)}ul,ol{margin:0 0 1rem;padding-left:1.25rem}button,input,select,textarea{font:inherit;color:inherit}button{cursor:pointer;border:0;background:none}:focus-visible{outline:2px solid var(--rk-primary);outline-offset:2px;border-radius:4px}::selection{background:color-mix(in srgb,var(--rk-primary) 26%,transparent)}.eyebrow{display:inline-flex;align-items:center;gap:.5rem;margin:0 0 .85rem;color:var(--rk-primary);font-size:.76rem;font-weight:760;letter-spacing:.14em;text-transform:uppercase}.eyebrow:before{content:"";width:18px;height:2px;background:currentColor;border-radius:2px}.lead{max-width:62ch;color:var(--rk-text-secondary);font-size:clamp(1.02rem,1.4vw,1.18rem)}.muted{color:var(--rk-text-secondary)}.small{font-size:.875rem}.mono{font-family:var(--rk-font-mono);font-size:.9em}.container{width:min(var(--rk-container),100% - var(--rk-gutter) * 2);margin-inline:auto}.section{padding-block:var(--rk-section-y)}.section--tint{background:var(--rk-surface-secondary);border-block:1px solid var(--rk-border)}.section__head{max-width:62ch;margin-bottom:clamp(2rem,4vw,3rem)}.section__head--center{margin-inline:auto;text-align:center}.stack{display:grid;gap:1rem}.grid{display:grid;gap:1.1rem}.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}.grid--4{grid-template-columns:repeat(4,minmax(0,1fr))}.grid--auto{grid-template-columns:repeat(auto-fit,minmax(240px,1fr))}.btn{display:inline-flex;align-items:center;justify-content:center;gap:.5rem;padding:.68rem 1.15rem;border:1px solid transparent;border-radius:var(--rk-radius);background:transparent;color:var(--rk-text);font-size:.94rem;font-weight:680;white-space:nowrap;transition:background var(--rk-transition),border-color var(--rk-transition),color var(--rk-transition),box-shadow var(--rk-transition),transform var(--rk-transition)}.btn:hover{transform:translateY(-1px)}.btn:active{transform:translateY(0)}.btn--primary{border-color:var(--rk-primary);background:var(--rk-primary);color:var(--rk-primary-contrast);box-shadow:var(--rk-shadow-sm)}.btn--primary:hover{border-color:var(--rk-primary-hover);background:var(--rk-primary-hover);color:var(--rk-primary-contrast)}.btn--secondary{border-color:var(--rk-border-strong);background:var(--rk-surface);color:var(--rk-text)}.btn--secondary:hover{border-color:var(--rk-primary);color:var(--rk-primary)}.btn--ghost{color:var(--rk-text-secondary)}.btn--ghost:hover{background:var(--rk-surface-secondary);color:var(--rk-text)}.btn--sm{padding:.42rem .75rem;font-size:.84rem}.btn--lg{padding:.82rem 1.5rem;font-size:1rem}.btn[disabled],.btn[aria-disabled=true]{opacity:.55;pointer-events:none;box-shadow:none}.btn-row{display:flex;flex-wrap:wrap;gap:.7rem;align-items:center}.card{display:flex;flex-direction:column;gap:.55rem;padding:clamp(1.1rem,2vw,1.5rem);border:1px solid var(--rk-border);border-radius:var(--rk-radius-lg);background:var(--rk-surface);box-shadow:var(--rk-shadow-xs);transition:border-color var(--rk-transition),box-shadow var(--rk-transition),transform var(--rk-transition)}.card--hover:hover{transform:translateY(-3px);border-color:var(--rk-border-strong);box-shadow:var(--rk-shadow-md)}.card--flat{box-shadow:none;background:transparent}.card--tint{background:var(--rk-surface-secondary);box-shadow:none}.card h3{margin:0}.card p{margin:0;color:var(--rk-text-secondary);font-size:.95rem}.card__icon{display:grid;place-items:center;width:40px;height:40px;border-radius:var(--rk-radius);background:var(--rk-primary-soft);color:var(--rk-primary);font-size:1.1rem;font-weight:800}.badge{display:inline-flex;align-items:center;gap:.35rem;padding:.2rem .6rem;border:1px solid var(--rk-border);border-radius:var(--rk-radius-pill);background:var(--rk-surface-secondary);color:var(--rk-text-secondary);font-size:.74rem;font-weight:700;letter-spacing:.02em;white-space:nowrap}.badge--primary{border-color:transparent;background:var(--rk-primary-soft);color:var(--rk-primary)}.badge--accent{border-color:transparent;background:var(--rk-accent-soft);color:var(--rk-accent)}.badge--success{border-color:transparent;background:var(--rk-success-soft);color:var(--rk-success)}.badge--warning{border-color:transparent;background:var(--rk-warning-soft);color:var(--rk-warning)}.badge__dot{width:6px;height:6px;border-radius:50%;background:currentColor}.notice{display:flex;gap:.85rem;padding:.95rem 1.1rem;border:1px solid var(--rk-border);border-left:3px solid var(--rk-primary);border-radius:var(--rk-radius);background:var(--rk-surface-secondary);color:var(--rk-text-secondary);font-size:.93rem}.notice strong{color:var(--rk-text)}.notice--warning{border-left-color:var(--rk-warning)}.notice--tip{border-left-color:var(--rk-success)}.table-wrap{overflow-x:auto;border:1px solid var(--rk-border);border-radius:var(--rk-radius)}table{width:100%;border-collapse:collapse;font-size:.92rem}th,td{padding:.7rem .9rem;text-align:left;border-bottom:1px solid var(--rk-border);vertical-align:top}th{background:var(--rk-surface-secondary);font-size:.78rem;font-weight:760;letter-spacing:.05em;text-transform:uppercase;color:var(--rk-text-secondary)}tbody tr:last-child td{border-bottom:0}.chip{display:inline-flex;align-items:center;gap:.45rem;padding:.45rem .8rem;border:1px solid var(--rk-border);border-radius:var(--rk-radius-pill);background:var(--rk-surface);color:var(--rk-text-secondary);font-size:.85rem;font-weight:600}.divider{height:1px;background:var(--rk-border);border:0;margin:0}.skip-link{position:absolute;top:-60px;left:1rem;z-index:300;padding:.6rem 1rem;border-radius:0 0 var(--rk-radius) var(--rk-radius);background:var(--rk-primary);color:var(--rk-primary-contrast);font-weight:680;transition:top var(--rk-transition)}.skip-link:focus{top:0;color:var(--rk-primary-contrast)}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}.skeleton{border-radius:var(--rk-radius);background:linear-gradient(90deg,var(--rk-surface-secondary),var(--rk-surface-tertiary),var(--rk-surface-secondary));background-size:200% 100%;animation:rk-shimmer 1.4s ease-in-out infinite}@keyframes rk-shimmer{0%{background-position:200% 0}to{background-position:-200% 0}}.page{min-height:calc(100vh - var(--rk-header-height) - 260px)}.page-hero{padding-block:clamp(3rem,6vw,5.5rem) clamp(2rem,4vw,3.5rem)}.page-hero__inner{max-width:74ch}.page-hero+.section{padding-top:clamp(1rem,2vw,1.75rem)}.prose{color:var(--rk-text);font-size:1rem;line-height:1.75}.prose>*:first-child{margin-top:0}.prose h1{margin:0 0 1.25rem;font-size:clamp(1.9rem,3.4vw,2.6rem)}.prose h2{margin:2.6rem 0 1rem;padding-top:.35rem;font-size:1.5rem}.prose h3{margin:2rem 0 .75rem;font-size:1.2rem}.prose h4{margin:1.6rem 0 .5rem;font-size:1.02rem}.prose h2,.prose h3,.prose h4{scroll-margin-top:calc(var(--rk-header-height) + 20px)}.prose p,.prose li{color:var(--rk-text-secondary)}.prose strong{color:var(--rk-text);font-weight:700}.prose ul,.prose ol{padding-left:1.35rem}.prose li{margin:.35rem 0}.prose li>ul,.prose li>ol{margin:.35rem 0}.prose a{text-decoration:underline;text-underline-offset:2px;text-decoration-color:color-mix(in srgb,var(--rk-primary) 45%,transparent)}.prose a:hover{text-decoration-color:currentColor}.prose hr{margin:2.5rem 0;border:0;border-top:1px solid var(--rk-border)}.prose img{border-radius:var(--rk-radius);border:1px solid var(--rk-border)}.prose blockquote{margin:1.5rem 0;padding:.9rem 1.15rem;border-left:3px solid var(--rk-primary);border-radius:0 var(--rk-radius) var(--rk-radius) 0;background:var(--rk-surface-secondary)}.prose blockquote p{margin:0;color:var(--rk-text-secondary)}.prose blockquote.is-warning{border-left-color:var(--rk-warning)}.prose blockquote.is-tip{border-left-color:var(--rk-success)}.prose code{font-family:var(--rk-font-mono);font-size:.88em}.prose :not(pre)>code{padding:.15em .38em;border:1px solid var(--rk-border);border-radius:var(--rk-radius-sm);background:var(--rk-code-inline-bg);color:var(--rk-text)}.prose pre{position:relative;margin:1.5rem 0;padding:1.1rem 1.2rem;overflow-x:auto;border-radius:var(--rk-radius);background:var(--rk-code-bg);color:var(--rk-code-text);font-size:.875rem;line-height:1.6}.prose pre code{color:inherit}.prose .code-block{position:relative}.prose .code-block__copy{position:absolute;top:.55rem;right:.55rem;padding:.25rem .55rem;border:1px solid rgba(255,255,255,.18);border-radius:var(--rk-radius-sm);background:#ffffff14;color:var(--rk-code-text);font-size:.72rem;font-weight:650;opacity:0;transition:opacity var(--rk-transition),background var(--rk-transition)}.prose .code-block:hover .code-block__copy{opacity:1}.prose .code-block__copy:hover{background:#ffffff2e}.prose .table-wrap{margin:1.5rem 0}.flex{display:flex}.flex-between{display:flex;align-items:center;justify-content:space-between;gap:1rem}.items-center{align-items:center}.wrap{flex-wrap:wrap}.gap-sm{gap:.5rem}.gap{gap:1rem}.gap-lg{gap:1.75rem}.mt-0{margin-top:0}.mt-2{margin-top:2rem}.mb-0{margin-bottom:0}.text-right{text-align:right}.w-full{width:100%}@media(max-width:1000px){.grid--4{grid-template-columns:repeat(2,minmax(0,1fr))}}@media(max-width:860px){.grid--3{grid-template-columns:repeat(2,minmax(0,1fr))}}@media(max-width:640px){.grid--2,.grid--3,.grid--4{grid-template-columns:1fr}.btn{width:100%}.btn-row .btn{width:auto;flex:1 1 auto}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{animation-duration:.001ms!important;transition-duration:.001ms!important}}