:root{--paper:#f7f4ee;--ink:#353b38;--muted:#62695e;--line:#dedbd1;--terra:#a65b3e;--soft:#eee8df;--green:#557361}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:24px}body{margin:0;background:var(--paper);color:var(--ink);font:16px/1.75 -apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif}a{color:inherit;text-decoration:none}button{font:inherit;cursor:pointer}button:disabled{cursor:not-allowed}h1,h2,h3,p,figure{margin:0}h1,h2,h3{line-height:1.3;letter-spacing:-.035em}img{max-width:100%;display:block}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid #b8704c;outline-offset:5px}[hidden]{display:none!important}.wrap{max-width:1180px;width:calc(100% - 72px);margin-inline:auto}.skip{position:fixed;top:10px;left:12px;transform:translateY(-170%);background:white;padding:8px;z-index:20}.skip:focus{transform:none}.masthead{display:flex;align-items:center;gap:27px;padding-block:23px;border-bottom:1px solid var(--line)}.brand{font-size:19px;font-weight:700;letter-spacing:-.035em;white-space:nowrap}.brand>span{font-size:25px;color:var(--terra);margin-right:8px}.masthead nav{display:flex;gap:29px;margin-left:auto;font-size:12px;color:#6a7167}.masthead nav a:hover{text-decoration:underline;text-underline-offset:6px}.registration-placeholder{border:1px solid #d8d8cd;background:#eeeee6;color:#7c8176;border-radius:5px;padding:5px 11px;line-height:1.5;font-size:10px}.registration-placeholder small{display:block;font-size:9px}.hero{display:grid;grid-template-columns:minmax(0,1.15fr) minmax(0,1fr);align-items:center;gap:54px;padding-block:61px 51px}.eyebrow{font-size:9px;font-weight:650;letter-spacing:.15em;color:#78634c;text-transform:uppercase;margin-bottom:17px}.hero h1{font-size:clamp(29px,3vw,41px);font-weight:650}.lead{font-size:clamp(27px,3.4vw,43px);line-height:1.45;margin-top:14px;letter-spacing:-.04em;color:#7c8378}.hero-description{font-size:13px;line-height:1.95;color:#60685b;max-width:480px;margin-top:22px}.official-button{display:flex;align-items:center;justify-content:space-between;gap:35px;background:var(--ink);color:#fff;padding:17px 20px;border-radius:6px;margin-top:26px;max-width:376px;font-size:15px;font-weight:600}.official-button:hover{background:#4a554b}.official-button small{display:block;color:#c0c9bd;font:11px/1.6 ui-monospace,monospace;font-weight:400;margin-top:3px}.official-button b{font-size:25px;font-weight:400}.identity{font-size:9px;color:#68705f;margin-top:12px}.identity strong{font-weight:500}.hero-figure img{width:100%;height:auto}.hero-figure figcaption{font-size:9px;text-align:center;color:#6e7463;margin-top:7px}.stage-strip{border-top:1px solid var(--line);border-bottom:1px solid var(--line);display:grid;grid-template-columns:repeat(3,1fr);padding-block:20px;gap:28px}.stage-strip>div{display:flex;align-items:center;gap:15px}.stage-strip>div>span{font:400 25px/1.5 ui-monospace,monospace;color:#b2b8a9}.stage-strip b{display:block;font-size:12px;font-weight:600}.stage-strip small{display:block;font-size:10px;color:#65705f;margin-top:4px}.reading-section{padding-top:65px}.section-heading{max-width:740px;margin-bottom:28px}.section-heading .eyebrow{margin-bottom:12px}.section-heading h2{font-size:32px}.section-heading>p:last-child{font-size:13px;line-height:1.9;color:var(--muted);margin-top:14px}.reading-layout{display:grid;grid-template-columns:254px minmax(0,1fr);gap:35px;align-items:start}.choice-panel{position:sticky;top:22px}.choices{background:#eee9df;padding:19px;border-radius:7px}.choices>p{font-size:10px;color:#6f654f;margin-bottom:15px}.choices>button{display:flex;align-items:center;text-align:left;width:100%;border:1px solid transparent;border-radius:5px;color:#6c7368;background:transparent;font-size:11px;gap:10px;padding:12px 7px;margin-top:3px}.choices>button>span{font:600 9px/1.8 ui-monospace,monospace;color:#9b8f7d;min-width:33px;flex-shrink:0}.choices>button>i{font-style:normal;font-size:12px;margin-left:auto}.choices>button:hover{background:#f7f4ed}.choices>button[aria-pressed=true]{background:#fff;border-color:#d8d2c4;color:#3f4b40}.choices>button[aria-pressed=true]>span{color:#a86b44}.choices>button.reset-choice{font-size:10px;text-align:center;justify-content:center;margin-top:14px;border-top:1px solid #d9d1c2;border-radius:0;padding-top:15px}.not-a-test{padding:22px 7px;color:#666f53}.not-a-test>b{font-size:10px;font-weight:600}.not-a-test>p{font-size:10px;line-height:1.95;margin-top:8px;max-width:215px}.selection-status{font-size:11px;color:#667052;margin-bottom:15px;min-height:20px}.problem-cards{display:grid;gap:13px}.problem-card{border:1px solid #dcded2;background:#fff;border-radius:7px;overflow:hidden}.problem-card summary{display:flex;align-items:center;gap:19px;padding:23px 25px;cursor:pointer;list-style:none}.problem-card summary::-webkit-details-marker{display:none}.code-badge{display:flex;align-items:center;justify-content:center;min-width:56px;height:49px;border:1px solid #d7dfd0;background:#f2f5ee;border-radius:5px;font:500 17px/1 ui-monospace,monospace;color:#768168}.problem-card summary small{display:block;color:#6b7458;font-size:9px;line-height:1.5}.problem-card summary strong{display:block;color:#485340;font-size:18px;font-weight:550;line-height:1.5;margin-top:3px}.expand-mark{margin-left:auto;font-size:23px;color:#9da38f;line-height:1}.problem-card[open] .expand-mark{transform:rotate(45deg)}.problem-card[open]{border-color:#b9c6ab}.problem-card[open] summary{border-bottom:1px solid #e3e8db;background:#fafcf6}.card-content{padding:25px}.message-example{background:#f4f5ef;border-left:3px solid #b3bca5;padding:14px 17px;overflow-wrap:anywhere}.message-example>span{font-size:9px;color:#626e50;display:block}.message-example code{font:500 12px/1.8 ui-monospace,monospace;display:block;color:#5c654f;margin-top:6px;white-space:normal;overflow-wrap:anywhere}.message-example small{display:block;font-size:9px;color:#6b7557;margin-top:7px}.meaning{font-size:13px;color:#667159;line-height:1.95;margin-top:19px}.check-steps{list-style:none;counter-reset:checks;margin:26px 0 0;padding:0}.check-steps li{counter-increment:checks;position:relative;padding-left:37px;margin-top:23px}.check-steps li:before{content:counter(checks,decimal-leading-zero);position:absolute;left:0;top:2px;color:#b1b799;font:11px/1.8 ui-monospace,monospace}.check-steps h3{font-size:15px;line-height:1.5;color:#4e5d42;font-weight:600}.check-steps p{font-size:12px;color:#626e50;line-height:2;margin-top:7px}.limits{display:grid;grid-template-columns:1fr 1fr;gap:13px;margin-top:28px}.limits>div{border-top:1px solid #e5e8dd;padding-top:15px}.limits b{font-size:10px;color:#6d775a;font-weight:600}.limits p{font-size:11px;color:#687254;line-height:1.95;margin-top:7px}.limits>div.stop{background:#f7eee5;padding:15px;border-top:0;border-radius:5px}.limits .stop b{color:#ac7850}.limits .stop p{color:#79624a}.next-step{font-size:11px;color:#7b8667;line-height:1.95;margin-top:24px}.next-step strong{display:block;font-size:10px;color:#526740;margin-bottom:4px}.card-sources{display:flex;gap:11px 16px;flex-wrap:wrap;border-top:1px solid #edf0e4;padding-top:16px;margin-top:22px;font-size:9px;color:#66734d}.card-sources>span{color:#66734d}.card-sources a:hover{text-decoration:underline}.support-section{display:grid;grid-template-columns:1fr 1fr;gap:70px;background:#e9eee1;border-radius:8px;padding:40px 42px;margin-top:65px}.support-section .eyebrow{color:#8d9878;margin-bottom:15px}.support-section h2{font-size:30px;color:#52613f;line-height:1.5}.support-section>div>p:not(.eyebrow){font-size:12px;line-height:2;color:#5d6d48;margin-top:17px}.support-link{display:inline-block;font-size:11px;border-bottom:1px solid #9caa86;color:#566943;margin-top:22px;padding-bottom:5px}.support-section aside{background:#f7faf0;padding:25px;border-radius:5px;align-self:center}.support-section h3{font-size:17px;color:#74805c}.support-section aside p{font-size:11px;line-height:1.95;color:#657345;margin-top:13px}.support-section strong{font-weight:600}.source-section{display:grid;grid-template-columns:1.1fr 1fr;gap:70px;padding-block:54px 39px}.source-section .eyebrow{margin-bottom:13px}.source-section h2{font-size:22px}.source-section p:last-child{font-size:11px;line-height:2;color:#66744f;margin-top:13px}.source-section ul{list-style:none;margin:0;padding:0}.source-section li{font-size:11px;color:#5d7149;border-bottom:1px solid #e1e5d6;padding-block:9px}.source-section a:hover{text-decoration:underline}.footer{font-size:9px;line-height:1.95;border-top:1px solid #dce3cf;padding-block:22px 30px;color:#68774f}
@media(max-width:950px){.wrap{width:calc(100% - 44px)}.hero{gap:25px}.hero h1{font-size:31px}.lead{font-size:32px}.hero-description{font-size:12px}.reading-layout{grid-template-columns:215px minmax(0,1fr);gap:22px}.choices{padding:15px}.choices>button{font-size:10px;padding-inline:4px;gap:7px}.problem-card summary{padding:20px;gap:15px}.problem-card summary strong{font-size:17px}.card-content{padding:21px}.support-section{gap:30px;padding:34px}.source-section{gap:35px}}
@media(max-width:700px){.wrap{width:calc(100% - 32px)}.masthead{flex-wrap:wrap;gap:12px;padding-block:17px}.brand{font-size:17px}.masthead nav{order:3;width:100%;margin:0;gap:27px;font-size:10px}.registration-placeholder{margin-left:auto;font-size:9px;padding:4px 9px}.registration-placeholder small{font-size:8px}.hero{grid-template-columns:1fr;padding-block:34px 28px;gap:24px}.hero h1{font-size:27px;line-height:1.4}.lead{font-size:29px;line-height:1.45;margin-top:12px}.eyebrow{font-size:8px;margin-bottom:14px}.hero-description{font-size:12px;margin-top:17px;line-height:1.9}.official-button{font-size:14px;padding:15px 18px;max-width:none;margin-top:21px}.official-button small{font-size:10px}.identity{font-size:8px;margin-top:11px}.hero-figure{max-width:440px;margin:auto;width:100%}.hero-figure figcaption{font-size:8px}.stage-strip{grid-template-columns:1fr;gap:14px;padding-block:19px}.stage-strip>div{gap:17px}.stage-strip>div>span{font-size:20px}.stage-strip b{font-size:11px}.stage-strip small{font-size:9px;margin-top:2px}.reading-section{padding-top:38px}.section-heading h2{font-size:27px}.section-heading>p:last-child{font-size:12px;line-height:1.9;margin-top:11px}.reading-layout{grid-template-columns:1fr;gap:15px}.choice-panel{position:static}.choices{display:grid;grid-template-columns:1fr 1fr;gap:6px;padding:13px}.choices>p{grid-column:1/3;margin:0 0 5px;font-size:9px}.choices>button{margin:0;line-height:1.6;padding:10px 7px;font-size:10px;gap:6px;min-height:49px}.choices>button>span{font-size:8px;min-width:26px}.choices>button>i{display:none}.choices>button.reset-choice{grid-column:1/3;min-height:38px;margin:6px 0 0;padding-top:12px;font-size:10px}.not-a-test{padding:12px 4px}.not-a-test>b{font-size:9px}.not-a-test>p{font-size:9px;max-width:none;margin-top:3px;line-height:1.8}.selection-status{font-size:9px;line-height:1.9;margin-bottom:11px}.problem-card summary{padding:18px 15px;gap:12px}.code-badge{min-width:46px;height:43px;font-size:15px}.problem-card summary small{font-size:8px}.problem-card summary strong{font-size:15px}.expand-mark{font-size:20px}.card-content{padding:17px}.message-example{padding:12px}.message-example code{font-size:10px}.message-example small{font-size:8px}.meaning{font-size:12px;line-height:2;margin-top:17px}.check-steps{margin-top:22px}.check-steps li{padding-left:29px;margin-top:20px}.check-steps h3{font-size:14px}.check-steps p{font-size:11px;line-height:2}.limits{grid-template-columns:1fr;gap:14px;margin-top:22px}.limits b{font-size:10px}.limits p{font-size:11px}.next-step{font-size:11px;margin-top:20px}.card-sources{font-size:8px;gap:9px 12px;margin-top:18px}.support-section{grid-template-columns:1fr;gap:25px;padding:27px 23px;margin-top:39px}.support-section h2{font-size:27px}.support-section>div>p:not(.eyebrow){font-size:11px;line-height:2}.support-section aside{padding:20px}.support-section h3{font-size:16px}.support-section aside p{font-size:11px}.source-section{grid-template-columns:1fr;gap:23px;padding-block:37px 30px}.source-section h2{font-size:21px}.source-section p:last-child{font-size:10px}.source-section li{font-size:10px}.footer{font-size:8px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}

.jump-link{display:inline-block;font-size:11px;color:#7e5e42;margin-top:12px;text-decoration:underline;text-underline-offset:4px}.section-heading>p a{text-decoration:underline;text-underline-offset:3px}