.rd-progress[data-astro-cid-d5qzx5jy]{position:fixed;top:0;left:0;height:3px;width:0;background:var(--c-purple);z-index:90;transition:width .1s linear}.rd-cols[data-astro-cid-d5qzx5jy]{display:block;transform:translateZ(0)}.rd-rail[data-astro-cid-d5qzx5jy],.rd-main[data-astro-cid-d5qzx5jy]{min-width:0}.rd-toc-side[data-astro-cid-d5qzx5jy]{display:none}@media(min-width:1200px){.rd-cols[data-astro-cid-d5qzx5jy]{display:grid;grid-template-columns:minmax(0,1fr) 220px;gap:44px}.rd-main[data-astro-cid-d5qzx5jy]{grid-column:1;grid-row:1}.rd-rail[data-astro-cid-d5qzx5jy]{grid-column:2;grid-row:1}.rd-toc-m[data-astro-cid-d5qzx5jy]{display:none}.rd-toc-side[data-astro-cid-d5qzx5jy]{display:block;position:sticky;top:76px;max-height:calc(100vh - 100px);overflow:auto;background:var(--c-bg);transform:translateZ(0)}}.rd-toc-side[data-astro-cid-d5qzx5jy] 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summary[data-astro-cid-d5qzx5jy]::-webkit-details-marker{display:none}.rd-guide[data-astro-cid-d5qzx5jy] summary[data-astro-cid-d5qzx5jy]:before{content:"▸";transition:transform .15s}.rd-guide[data-astro-cid-d5qzx5jy][open] summary[data-astro-cid-d5qzx5jy]:before{transform:rotate(90deg)}.rd-guide-body[data-astro-cid-d5qzx5jy]{padding:12px 18px 14px;border-top:1px dashed var(--c-line);margin:0}.rd-why[data-astro-cid-d5qzx5jy]{font-size:13.5px;line-height:1.8;color:var(--c-body2);margin:0 0 10px}.rd-why-label[data-astro-cid-d5qzx5jy]{display:inline-block;font-size:11.5px;font-weight:700;color:var(--c-purple);background:var(--c-purple-bg);border-radius:var(--r-chip);padding:1px 8px;margin-right:8px;vertical-align:1px}.rd-digest[data-astro-cid-d5qzx5jy]{margin:0 0 12px;padding-left:20px}.rd-digest[data-astro-cid-d5qzx5jy] li[data-astro-cid-d5qzx5jy]{font-size:13.5px;line-height:1.9;color:var(--c-fg);margin-bottom:4px}.rd-pre[data-astro-cid-d5qzx5jy]{display:flex;flex-wrap:wrap;align-items:center;gap:8px}.rd-pre-label[data-astro-cid-d5qzx5jy]{font-size:11.5px;font-weight:700;color:var(--c-muted)}.rd-pre-chip[data-astro-cid-d5qzx5jy]{font-size:12px;color:var(--c-nav);text-decoration:none;border:1px solid var(--c-line);background:var(--c-chip-bg);border-radius:var(--r-chip);padding:3px 10px}.rd-pre-chip[data-astro-cid-d5qzx5jy]:hover{border-color:var(--c-cy);color:var(--c-cy-deep)}.rd-toolbar[data-astro-cid-d5qzx5jy]{display:flex;align-items:center;gap:8px;margin:16px 0}.rd-mode[data-astro-cid-d5qzx5jy]{font-size:13px;padding:5px 14px;border-radius:999px;cursor:pointer;border:1px solid var(--c-line);background:var(--c-card);color:var(--c-body2)}.rd-mode[data-astro-cid-d5qzx5jy].active{border-color:var(--c-purple);color:var(--c-purple);background:var(--c-purple-bg);font-weight:600}.rd-count[data-astro-cid-d5qzx5jy]{margin-left:auto;font-size:12px;color:var(--c-muted)}.rd-resume[data-astro-cid-d5qzx5jy]{font-size:12px;cursor:pointer;color:var(--c-purple);font-weight:600;border:1px solid var(--c-purple);background:var(--c-purple-bg);border-radius:999px;padding:3px 12px}.rd-fs[data-astro-cid-d5qzx5jy]{display:flex;gap:4px;margin-left:6px}.rd-fsbtn[data-astro-cid-d5qzx5jy]{font-size:11.5px;padding:4px 8px;border-radius:8px;cursor:pointer;border:1px solid var(--c-line);background:var(--c-card);color:var(--c-body2)}.rd-fsbtn[data-astro-cid-d5qzx5jy].active{border-color:var(--c-cy);color:var(--c-cy-deep);background:var(--c-cy-bg);font-weight:600}.rd-feynman[data-astro-cid-d5qzx5jy]{margin:16px 0 0;border:1px dashed 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a[data-astro-cid-d5qzx5jy].rd-toc-link:hover{color:var(--c-cy-deep)}.rd-hot[data-astro-cid-d5qzx5jy]{display:inline-block;font-size:11px;font-weight:700;margin-right:8px;vertical-align:2px;color:#9a6700;background:#fcedc8;border:1px solid rgba(232,178,61,.4);border-radius:var(--r-chip);padding:1px 8px;cursor:help;position:relative}[data-theme=dark] .rd-hot[data-astro-cid-d5qzx5jy]{color:var(--c-amber);background:#e8b23d1f}.rd-tnc[data-astro-cid-d5qzx5jy]{display:inline-block;font-size:11px;font-weight:700;margin-left:8px;vertical-align:2px;color:var(--c-purple);background:var(--c-purple-bg);border-radius:var(--r-chip);padding:1px 8px;cursor:help;position:relative}.rd-body[data-astro-cid-d5qzx5jy]{margin-top:8px}.rd-code[data-astro-cid-d5qzx5jy]{font-size:12.5px;line-height:1.6;margin:14px 0;padding:14px 16px;background:var(--c-chip-bg, rgba(0,0,0,.04));border:1px solid 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* var(--rd-fs, 1));line-height:1.95;color:var(--c-fg);border-left:2px solid var(--c-line);padding-left:16px}@media(max-width:960px){.pair[data-astro-cid-d5qzx5jy]{grid-template-columns:1fr;gap:6px}.pair[data-astro-cid-d5qzx5jy] .en[data-astro-cid-d5qzx5jy]{font-size:calc(13.5px * var(--rd-fs, 1))}.pair[data-astro-cid-d5qzx5jy] .zh[data-astro-cid-d5qzx5jy]{padding-left:12px}}.rd-body[data-astro-cid-d5qzx5jy].en .zh[data-astro-cid-d5qzx5jy],.rd-body[data-astro-cid-d5qzx5jy].zh .en[data-astro-cid-d5qzx5jy]{display:none}.rd-body[data-astro-cid-d5qzx5jy].zh .pair[data-astro-cid-d5qzx5jy]{grid-template-columns:minmax(0,1fr)}.rd-body[data-astro-cid-d5qzx5jy].zh .pair[data-astro-cid-d5qzx5jy] .zh[data-astro-cid-d5qzx5jy]{border-left:none;padding-left:0}.rd-quiz[data-astro-cid-d5qzx5jy]{margin:40px 0 0;border:1px solid var(--c-line);border-radius:var(--r-card);background:var(--c-card);padding:18px 20px}.rd-quiz-title[data-astro-cid-d5qzx5jy]{font-size:16px;margin:0 0 4px}.rd-quiz-hint[data-astro-cid-d5qzx5jy]{font-size:12.5px;color:var(--c-muted);margin:0 0 12px}.rd-q[data-astro-cid-d5qzx5jy]{border-top:1px dashed var(--c-line);padding:10px 0 2px}.rd-q[data-astro-cid-d5qzx5jy] summary[data-astro-cid-d5qzx5jy]{cursor:pointer;font-size:14px;line-height:1.7;color:var(--c-fg);list-style:none}.rd-q[data-astro-cid-d5qzx5jy] summary[data-astro-cid-d5qzx5jy]::-webkit-details-marker{display:none}.rd-q[data-astro-cid-d5qzx5jy] summary[data-astro-cid-d5qzx5jy]:before{content:"▸ ";color:var(--c-purple)}.rd-q[data-astro-cid-d5qzx5jy][open] summary[data-astro-cid-d5qzx5jy]:before{content:"▾ "}.rd-q-n[data-astro-cid-d5qzx5jy]{display:inline-block;font-size:11.5px;font-weight:700;color:var(--c-purple);background:var(--c-purple-bg);border-radius:var(--r-chip);padding:1px 7px;margin-right:8px;vertical-align:1px}.rd-q-a[data-astro-cid-d5qzx5jy]{font-size:13.5px;line-height:1.9;color:var(--c-body2);margin:8px 0 6px;padding-left:4px}.rd-back[data-astro-cid-d5qzx5jy]{margin:30px 0 44px}.rd-back[data-astro-cid-d5qzx5jy] a[data-astro-cid-d5qzx5jy]{font-size:13px;color:var(--c-nav);text-decoration:none}.rd-back[data-astro-cid-d5qzx5jy] a[data-astro-cid-d5qzx5jy]:hover{color:var(--c-cy-deep)}.pair .zh .term{background:var(--c-purple-bg);border-radius:4px;padding:1px 3px;cursor:help;position:relative;-webkit-box-decoration-break:clone;box-decoration-break:clone}.note-card{display:none;position:absolute;bottom:calc(100% + 8px);left:50%;transform:translate(-50%);width:max-content;max-width:340px;text-align:left;background:var(--c-card);border:1px solid var(--c-line);border-radius:12px;box-shadow:0 12px 36px #16181d2e;padding:12px 14px;font-size:12.5px;line-height:1.75;color:var(--c-fg);font-weight:400;cursor:auto;z-index:70}.term:hover .note-card,.term.open .note-card,.rd-hot:hover .note-card,.rd-hot.open .note-card,.rd-tnc:hover .note-card,.rd-tnc.open 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header.hero,body.rd-reading footer.cta,body.rd-reading .rd-rail,body.rd-reading .rd-badge,body.rd-reading .rd-src,body.rd-reading .rd-guide,body.rd-reading .rd-quiz,body.rd-reading .rd-back,body.rd-reading .rd-toolbar,body.rd-reading .rd-feynman{display:none!important}body.rd-reading .rd-cols{grid-template-columns:minmax(0,1fr)}body{transition:background-color .6s ease}body.rd-reading{--c-bg: #f6f1e7;--c-card: #fdfaf3;--c-chip-bg: #efe8d8;--c-line: #e6ddc9;background-color:#f6f1e7}[data-theme=dark] body.rd-reading{--c-bg: #0b0d10;--c-card: #14171b;--c-chip-bg: #1a1e23;--c-line: #24282e;background-color:#0b0d10}body.rd-reading .pair .en{font-family:Georgia,Times New Roman,Songti SC,serif;line-height:1.95}body.rd-reading .pair .zh{font-family:Songti SC,"Noto Serif SC",STSong,SimSun,serif;line-height:2.08;text-align:justify}body.rd-reading .rd-body h2{font-family:Songti SC,"Noto Serif SC",STSong,SimSun,serif}@keyframes rd-settle{0%{opacity:0;transform:translateY(12px);filter:blur(3px)}to{opacity:1;transform:translateY(0);filter:blur(0)}}body.rd-reading .rd-cols{animation:rd-settle .7s ease-out both}@keyframes rd-bar-in{0%{opacity:0;transform:translate(-50%,10px)}to{opacity:1;transform:translate(-50%)}}.rd-readingbar{display:none;position:fixed;left:50%;transform:translate(-50%);bottom:max(14px,env(safe-area-inset-bottom));z-index:85;align-items:center;gap:6px;padding:6px 10px;background:var(--c-card);border:1px solid var(--c-line);border-radius:999px;box-shadow:0 10px 30px #16181d29}body.rd-reading .rd-readingbar{display:flex;animation:rd-bar-in .5s ease-out .25s both}.rd-mini{font-size:12px;padding:4px 12px;border-radius:999px;border:none;background:none;color:var(--c-body2);cursor:pointer}.rd-mini:hover{color:var(--c-fg)}.rd-mini-mode.active{color:var(--c-purple);background:var(--c-purple-bg);font-weight:600}.rd-mini-sep{width:1px;height:14px;background:var(--c-line);margin:0 2px}.rd-fy-hint{font-size:13px;color:var(--c-muted);margin:0 0 10px}.rd-fy-digest{margin:0 0 14px;padding-left:20px}.rd-fy-digest li{font-size:13.5px;line-height:1.9;margin-bottom:4px}.rd-fy-sec{font-size:15px;margin:18px 0 8px;padding-bottom:6px;border-bottom:1px solid var(--c-line)}.rd-fy-terms{display:flex;flex-wrap:wrap;gap:8px}.rd-fy-term{font-size:12.5px;color:var(--c-nav);background:var(--c-chip-bg);border:1px solid var(--c-line);border-radius:var(--r-chip);padding:2px 10px}