:root{color-scheme:dark;--ground:#0c0c0e;--panel:#17171b;--ink:#f7f4f1;--quiet:#bdbac3;--rule:#36353b;--red:#fa7771;--redfill:#f77b73;--darkred:#260f12;--metal:#797980;--measure:1180px}
*{box-sizing:border-box}html{scroll-padding-top:1.2rem}body{margin:0;background:var(--ground);color:var(--ink);font:16px/1.72 system-ui,"PingFang SC","Microsoft YaHei",sans-serif}img{max-width:100%;display:block}a{color:var(--red);text-underline-offset:.24em}a:focus-visible,summary:focus-visible{outline:3px solid #ffa6a1;outline-offset:5px}p,h1,h2,h3{margin-top:0}h1,h2,h3{line-height:1.15;letter-spacing:-.032em}h2{font-size:clamp(1.55rem,3vw,2.22rem)}h3{font-size:1.09rem}p{margin-bottom:.85em}main,section,article{min-width:0}.bounds{width:min(calc(100% - 48px),var(--measure));margin-inline:auto}.skip{position:absolute;top:9px;left:-200vw}.skip:focus{left:12px;padding:9px;background:#fff;color:#17171b;z-index:5}
.top-rail{border-bottom:1px solid var(--rule);background:#101013}.top-rail .bounds{display:flex;align-items:center;justify-content:space-between;gap:12px;min-height:64px}.mark{display:flex;align-items:center;gap:9px;color:var(--ink);font-weight:820;text-decoration:none;white-space:nowrap}.mark img{width:26px;height:26px}.top-rail nav{display:flex;gap:clamp(12px,3vw,29px);align-items:center;font-size:.9rem;white-space:nowrap}.top-rail nav a{color:var(--quiet);text-decoration:none;display:inline-flex;align-items:center;min-height:44px}.top-rail nav span{color:var(--ink);font-weight:750}
.opening{display:grid;grid-template-columns:44% 56%;align-items:stretch;border-bottom:1px solid var(--rule)}.pitch{align-self:center;padding:clamp(27px,4.9vw,64px) clamp(14px,3.5vw,45px) clamp(24px,4.1vw,54px) 0}.tag,.branch-name,.section-code{font:750 .73rem/1.35 ui-monospace,monospace;letter-spacing:.125em;color:#f5a29d}.tag{display:block;margin-bottom:15px}.opening h1{font-size:clamp(2.7rem,5vw,5rem);margin-bottom:17px}.opening h1 span{display:block;color:#ebe3e3;font-size:.54em;letter-spacing:-.024em;margin-top:13px;line-height:1.28}.first-answer{max-width:28rem;color:#d8d2d4;margin-bottom:18px}.action-row{display:flex;gap:9px;flex-wrap:wrap}.control{display:inline-flex;min-height:46px;align-items:center;background:var(--redfill);color:#180d0e;border:1px solid var(--redfill);border-radius:4px;font-weight:810;text-decoration:none;padding:.5em .86em}.control.secondary{background:#21181b;color:#fff2ef;border-color:#806367}.control:hover{filter:brightness(1.13)}.assembly{margin:0;position:relative;align-self:end;overflow:hidden;background:#0c0c0e;border:1px solid #28262a;border-bottom:0}.assembly img{width:100%;height:auto;aspect-ratio:1200/676;object-fit:contain}.assembly::before,.assembly::after{content:"";position:absolute;z-index:1;top:10px;width:13px;height:13px;border-top:1px solid #a8a3a6;pointer-events:none}.assembly::before{left:10px;border-left:1px solid #a8a3a6}.assembly::after{right:10px;border-right:1px solid #a8a3a6}
.manifold{position:relative;padding-top:69px}.pipes{position:absolute;top:-1px;left:0;right:0;height:72px;pointer-events:none;--steel:linear-gradient(90deg,#34343a,#87868b 47%,#d2d2d8 58%,#42424b 84%)}.pipes i{position:absolute;top:0;width:10px;background:var(--steel);height:63px}.pipes i:first-child{left:63.9%;height:26px}.pipes i:first-child::after{position:absolute;content:"";width:min(37vw,440px);height:38px;right:0;top:22px;border-radius:0 11px 0 14px;border-top:8px ridge #85838b;border-left:8px ridge #85838b}.pipes i:last-child{left:78.8%}.pipes i:last-child::after{content:"";position:absolute;bottom:-5px;left:-4px;width:18px;height:7px;border-radius:3px;background:#a09da8}.line-pair{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:18px}.branch{position:relative;background:linear-gradient(155deg,#1b1b1f,#111114 68%);border:1px solid #414047;padding:clamp(18px,3vw,34px);border-top:3px solid #aa6666}.branch:nth-child(2){border-top-color:#8c8f9a}.branch-name{display:block;margin-bottom:9px}.branch h2{margin-bottom:12px}.branch p{color:var(--quiet)}.inspection{padding-left:1.35rem;margin:17px 0}.inspection li{padding-left:.25em;margin-bottom:.58rem}.decision{display:grid;margin:16px 0 18px;gap:0}.decision div{padding:.58rem 0;border-top:1px solid #39383f}.decision dt{font-weight:770}.decision dd{margin:0;color:var(--quiet);font-size:.94rem}.branch a{font-weight:760}
.reference-band{margin-top:clamp(29px,5vw,60px);padding:25px 0 52px;border-top:1px solid var(--rule)}.reference-band h2{margin-bottom:15px}.work-list{display:grid;gap:0}.work-entry{padding:13px 0 14px;border-bottom:1px solid var(--rule)}.work-entry h3{margin-bottom:7px}.work-entry p{margin:0;color:var(--quiet)}.work-entry a{color:var(--ink);font-weight:780}.foot-rail{border-top:1px solid var(--rule);padding:23px 0;background:#121216}.foot-rail .bounds{display:flex;gap:20px;justify-content:space-between;align-items:flex-start}.foot-rail p{margin:3px 0 0;color:var(--quiet);font-size:.87rem}.foot-rail nav{display:flex;gap:14px;white-space:nowrap;font-size:.89rem}
.field-main{max-width:860px;padding:32px 0 65px}.field-main h1{font-size:clamp(1.95rem,5vw,3.7rem);margin-bottom:15px}.field-main h2{font-size:clamp(1.27rem,3.1vw,1.75rem);margin:1.48em 0 .45em}.crumb{display:flex;flex-wrap:wrap;align-items:center;gap:8px;color:var(--quiet);font-size:.84rem;margin:0 0 19px}.field-note,.field-sheet{border-top:4px solid #a45857;background:#151519;padding:clamp(17px,4vw,35px);border-inline:1px solid var(--rule);border-bottom:1px solid var(--rule)}.field-note time{display:block;color:var(--quiet);font-size:.84rem;margin-bottom:16px}.opening-result{background:#29191e;border-left:4px solid #ff8c85;padding:12px 15px;color:#fff1ef}.field-body p{color:#e2dde2}.field-body a,.field-sheet a{font-weight:700}.field-body ol,.field-body ul{padding-left:1.4rem}.field-body li{margin-bottom:.55em}.faults{margin:0;display:grid;gap:9px}.faults div{padding:12px 14px;border-left:3px solid #76727d;background:#222126}.faults dt{font-weight:790}.faults dd{margin:2px 0 0;color:#e3dfe4}.field-links{display:flex;flex-wrap:wrap;gap:11px 21px;padding-top:17px;margin-top:22px;border-top:1px solid var(--rule)}
@media(max-width:760px){.bounds{width:calc(100% - 36px)}.opening{grid-template-columns:1fr}.pitch{padding:29px 0 22px}.opening h1{font-size:clamp(2.38rem,9vw,3.55rem);margin-bottom:12px}.opening h1 span{font-size:.58em;margin-top:7px}.tag{margin-bottom:10px}.first-answer{margin-bottom:14px}.assembly img{height:auto}.manifold{padding-top:28px}.pipes{height:27px}.pipes i:first-child{left:35.8%;height:30px}.pipes i:first-child::after{display:none}.pipes i:last-child{left:61.7%;height:20px}.pipes i:last-child::after{display:none}.line-pair{grid-template-columns:1fr;border-left:4px ridge #74747b;padding-left:10px;gap:14px}.branch{padding:16px}.branch::before{content:"";position:absolute;top:24px;left:-13px;width:12px;border-top:4px ridge #74747b}.top-rail .bounds{min-height:54px}.top-rail nav{gap:11px;font-size:.81rem}.mark{font-size:.91rem;gap:5px}.mark img{width:22px;height:22px}.foot-rail .bounds{display:block}.foot-rail nav{margin-top:9px}.field-main{padding:23px 0 45px}.reference-band{padding:23px 0 35px}}
@media(max-width:355px){.top-rail .bounds{width:calc(100% - 24px)}.top-rail nav{gap:7px;font-size:.77rem}.control{font-size:.92rem}}
@media(min-width:761px){.opening h1 span{font-size:.48em}}
@media(max-width:760px){.pipes i:first-child{left:0;width:36.7%;height:30px;background:none}.pipes i:first-child::before{content:"";position:absolute;right:0;top:0;width:8px;height:16px;background:var(--steel)}.pipes i:first-child::after{display:block;left:0;right:0;top:12px;width:auto;height:16px;border-radius:8px 0 0 0;border-top:4px ridge #85838b;border-left:4px ridge #85838b}.pipes i:last-child{width:8px;height:16px}.pipes i:last-child::after{display:block;top:12px;left:auto;right:0;width:calc(26vw - 9px);height:4px;background:#85838b;border-radius:0}}