@font-face{font-family:Remi;src:url("./remi-sans.woff2") format("woff2");font-weight:100 900;font-display:swap}
/* Remi is cut to the characters a build ships; anything else (a syllable typed into a field, a symbol the face lacks) is drawn by a Korean system face. */
:root{--remi-font:Remi,"Apple SD Gothic Neo","Malgun Gothic","Noto Sans KR","Noto Sans CJK KR",Arial,sans-serif}
:root{--ink:#25343c;--muted:#617079;--blue:#087fa4;--purple:#845cb2;--positive:#16816f;--negative:#ba6552;--paper:#fff;--line:#dce3e4;--figure-rule:#36535f}
/* The textbook's one reading column: text, equations, lists, tables, details, figures and placeholders all share its width. */
:root{--column:840px;--figure-gap:48px}
*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--remi-font)}a{color:#087295;text-underline-offset:4px}button,input,select{font:inherit}button{cursor:pointer}button:focus-visible,a:focus-visible,input:focus-visible,summary:focus-visible{outline:3px solid #e3a541;outline-offset:4px}button:disabled{cursor:default}.skip-link{position:absolute;top:-100px;left:15px;z-index:10;background:white;padding:12px}.skip-link:focus{top:10px}
.family-header{display:flex;align-items:center;gap:24px;padding:8px 34px;border-bottom:1px solid var(--line);min-height:70px}.family-header img{display:block;width:115px;height:49px;object-fit:contain}.book-brand{font-size:14px;color:var(--ink);text-decoration:none;border-left:1px solid var(--line);padding-left:24px}.family-header nav{display:flex;gap:24px;margin-left:auto;font-size:13px}.family-header nav a{text-decoration:none;color:var(--muted)}.family-links{display:flex;gap:25px;border-bottom:1px solid var(--line);padding:10px 34px;font-size:12px;overflow:auto;white-space:nowrap}.family-links a{text-decoration:none;color:var(--muted)}.family-header nav a[aria-current=page],.family-links a[aria-current=page]{color:#0079a8;font-weight:600;text-decoration:underline;text-decoration-color:#0087bb;text-decoration-thickness:2px;text-underline-offset:6px}
.book-layout{display:grid;grid-template-columns:246px minmax(0,1fr);max-width:1600px;margin:auto}.book-sidebar{border-right:1px solid var(--line);background:#f8faf9;min-width:0;padding:33px 21px}.book-sidebar details{position:sticky;top:25px;max-height:calc(100vh - 50px);overflow-y:auto}.book-sidebar summary{display:none}.course-name{font-size:18px;font-weight:650;margin:0 0 22px}.course-name small{display:block;font-size:11px;color:var(--muted);font-weight:400;margin-top:6px}.book-sidebar ol{padding:0;margin:0;list-style:none}.book-sidebar li{margin:1px 0}.book-sidebar li a,.not-yet{display:flex;gap:9px;align-items:baseline;padding:11px 8px;font-size:12px;line-height:1.5;text-decoration:none;color:var(--ink)}.book-sidebar li a>span,.not-yet>span{font-size:10px;color:var(--muted);min-width:16px}.book-sidebar li a[aria-current]{background:#e8f2f4;color:#075873;border-radius:3px;font-weight:650}.not-yet{color:#6e7a80;flex-wrap:wrap}.not-yet small{font-size:9px;margin-left:25px;color:#71818a}.sidebar-home{font-size:11px;display:block;margin:26px 8px}.book-sidebar li a.current-chapter{font-weight:650;color:#075873}.book-sidebar .chapter-pages{margin:0 0 10px 24px;border-left:1px solid var(--line)}.book-sidebar .chapter-pages a{padding:6px 8px 6px 10px;font-size:11.5px;line-height:1.45}
main{min-width:0;padding:38px 56px 70px}.reading-width{max-width:var(--column);margin:0 auto}.chapter-kicker{font-size:11px;letter-spacing:.05em;color:var(--muted);margin:0 0 13px}.chapter-kicker span{margin-left:12px}article{font-size:17px;line-height:1.95;word-break:keep-all;overflow-wrap:break-word}article [data-figure]{word-break:normal;overflow-wrap:normal}
/* A list item that holds a built-up fraction (e.g. choices written with \dfrac) gets room so stacked fractions do not touch. */
article li:has(.katex .mfrac){margin:.55em 0}h1{font-size:36px;font-weight:680;letter-spacing:-.035em;line-height:1.4;margin:0 0 24px}h2{font-size:23px;line-height:1.5;letter-spacing:-.02em;margin:40px 0 14px}h3{font-size:18px;margin-top:24px}p{margin:15px 0}.lead{font-size:20px;color:#415963;line-height:1.8;margin-bottom:28px}strong{font-weight:650}blockquote{margin:28px 0;padding:3px 20px;border-left:3px solid var(--blue);color:#3b5361;background:#f5f9f9}article ul,article ol{padding-left:23px}code{font-family:ui-monospace,monospace;font-size:.85em;background:#f0f4f4;padding:.1em .3em;border-radius:3px}pre{padding:18px;background:#f4f6f6;overflow:auto;line-height:1.55;font-size:14px}pre code{padding:0;background:none}.katex-display{overflow-x:auto;overflow-y:hidden;padding:8px 0;margin:22px 0}.katex{font-size:1.03em}
.concept-figure{margin:var(--figure-gap) 0;border-top:2px solid var(--figure-rule);border-bottom:1px solid var(--line);padding:19px 0 14px;line-height:1.5;font-size:14px}.figure-heading{font-size:18px;font-weight:650;margin:0 0 7px}.figure-subtitle{color:var(--muted);font-size:13px;margin:0 0 19px}.figure-controls{display:flex;flex-wrap:wrap;align-items:center;gap:14px 28px;background:#f2f7f7;padding:14px 16px;margin-bottom:18px}.figure-controls label{font-size:13px;display:flex;gap:9px;align-items:center}.figure-controls input[type=range]{width:150px;accent-color:var(--blue);min-height:26px}.figure-controls output{font-variant-numeric:tabular-nums;min-width:43px;color:#075873;font-weight:650}.figure-controls select{border:1px solid #b9cdd2;background:white;border-radius:3px;padding:5px}.figure-controls input[type=checkbox]{width:16px;height:16px;accent-color:var(--blue)}.figure-controls button{font-size:12px;padding:6px 9px;border:1px solid #b9cdd2;background:white;border-radius:3px;color:#385c69}
.inner-product-board{display:grid;grid-template-columns:minmax(0,3fr) minmax(150px,1fr);gap:15px}.comparison-lanes{display:grid;gap:19px}.comparison-lane{display:grid;grid-template-columns:1fr 1fr;gap:16px;position:relative}.comparison-lane:after{content:"→";position:absolute;left:calc(50% - 7px);top:80px;color:#78909a;background:white;padding:2px}.plot-label{font-size:12px;line-height:1.6;margin:0 0 5px}.plot-label strong{font-weight:600}.plot{min-width:0}.plot svg{width:100%;height:145px;display:block;overflow:visible}.plot svg text{font-family:var(--remi-font);font-size:11px;fill:#617079}.plot svg .axis{stroke:#b4c3c8;stroke-width:1}.plot svg .grid{stroke:#e8eded;stroke-width:1}.coefficient-panel{display:flex;flex-direction:column;justify-content:center;border-left:1px solid #dce5e5;padding-left:15px}.coefficient-panel .plot svg{height:170px}.projection-values{display:flex;justify-content:space-between;gap:9px;font-size:12px;margin:7px 0}.projection-values output{font-size:18px;font-variant-numeric:tabular-nums;color:var(--ink);font-weight:600}.figure-reading{padding:12px 14px;background:#f2f7f4;font-size:14px;line-height:1.75;margin:18px 0 10px;min-height:50px}.figure-credit{font-size:11px;color:var(--muted);line-height:1.7;margin:12px 0 0}.legend{display:flex;gap:16px;flex-wrap:wrap;font-size:11px;color:var(--muted);margin:7px 0}.legend span:before{content:"";display:inline-block;width:13px;height:3px;background:var(--legend);margin-right:5px;vertical-align:middle}.formula-line{font-size:14px;margin:8px 0}
.source-note{border-top:1px solid var(--line);margin-top:42px;padding-top:17px;font-size:12px;color:var(--muted);line-height:1.8}.source-note h2{font-size:14px;margin:0 0 10px}.source-note ul{padding-left:17px}.page-nav{word-break:keep-all;display:grid;grid-template-columns:minmax(0,1fr) auto minmax(0,1fr);gap:18px;align-items:end;font-size:13px;line-height:1.55;padding:0 0 14px;margin:0 0 26px;border-bottom:1px solid var(--line)}.page-nav a{text-decoration:none;color:#075873}.page-nav a:hover{text-decoration:underline}.page-nav small{display:block;font-size:11px;color:var(--muted)}.page-next{text-align:right}.page-count{margin:0;font-size:12px;color:var(--muted);white-space:nowrap;align-self:center}.page-nav:last-child{border-bottom:0;border-top:1px solid var(--line);padding:16px 0 0;margin:var(--figure-gap) 0 0}.page-chapter{font-size:13px;color:var(--muted);margin:0 0 4px}.page-chapter+article>h2:first-child{margin-top:0}.chapter-list{margin:25px 0}.chapter-list a{display:flex;gap:18px;align-items:center;padding:19px 0;border-bottom:1px solid var(--line);text-decoration:none;font-size:16px}.chapter-list a>span{font-size:12px;color:var(--muted)}.chapter-list a>span:last-child{margin-left:auto}.quiet{font-size:13px;color:var(--muted);line-height:1.8}.library-index{max-width:930px;margin:45px auto;padding:30px}.library-index .lead{max-width:650px}
@media(max-width:1100px){.book-layout{grid-template-columns:205px minmax(0,1fr)}.book-sidebar{padding:30px 13px}main{padding:30px 34px 60px}h1{font-size:31px}.inner-product-board{gap:9px;grid-template-columns:minmax(0,3fr) minmax(135px,1fr)}}
@media(max-width:820px){.book-layout{display:block}.book-sidebar{padding:0 20px;border-right:none;border-bottom:1px solid var(--line);background:#f5f8f7}.book-sidebar details{position:static;max-height:none;overflow:visible}.book-sidebar summary{display:list-item;padding:13px 0;font-size:13px;cursor:pointer}.book-sidebar ol{padding-bottom:14px;columns:2}.book-sidebar li:has(.chapter-pages){break-inside:avoid}.book-sidebar .chapter-pages{columns:1;padding-bottom:0}.course-name{display:none}.not-yet small{display:none}.sidebar-home{display:none}main{padding:28px 28px 50px}:root{--column:720px}.family-header{padding:7px 20px;gap:15px}.family-links{padding:9px 20px;gap:22px}.family-header nav{gap:16px}.book-brand{padding-left:15px}}
@media(max-width:540px){main{padding:24px 20px 42px}h1{font-size:29px}h2{font-size:22px}article{font-size:16px;line-height:1.9}.lead{font-size:18px}.family-header img{width:90px;height:40px}.family-header{min-height:61px;padding:7px 16px;gap:10px}.book-brand{font-size:12px;padding-left:10px}.family-header nav{font-size:10px;gap:12px}.family-links{font-size:11px;padding:9px 16px;gap:19px}.book-sidebar{padding:0 20px}.book-sidebar ol{columns:1}.concept-figure{padding-top:14px}.page-nav{grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:8px 14px}.page-count{grid-column:1/-1;grid-row:1}.figure-heading{font-size:17px}.figure-subtitle{font-size:12px;line-height:1.6}.figure-controls{gap:8px 15px;padding:10px;margin-bottom:14px}.figure-controls label{font-size:12px}.figure-controls input[type=range]{width:110px}.figure-controls select{max-width:130px}.inner-product-board{display:block}.comparison-lanes{gap:15px}.comparison-lane{gap:15px}.plot-label{font-size:11px;min-height:33px}.plot svg{height:128px}.comparison-lane:after{top:70px}.coefficient-panel{display:grid;grid-template-columns:140px minmax(0,1fr);column-gap:15px;border-left:0;border-top:1px solid var(--line);padding:10px 0 0;margin-top:13px}.coefficient-panel>.plot{grid-column:1;grid-row:1/4}.coefficient-panel .plot-label{min-height:0}.coefficient-panel .plot svg{height:112px}.coefficient-panel .projection-values{grid-column:2;margin:8px 0;align-self:center}.coefficient-panel .formula-line{grid-column:2;margin:0;font-size:12px;align-self:center}.projection-values output{font-size:16px}.figure-reading{font-size:13px;padding:10px;margin:12px 0 8px}.figure-credit{font-size:10px}.legend{gap:11px;margin-top:0}.library-index{margin:20px auto}}
.impulse-system{display:flex;align-items:center;justify-content:center;gap:18px;padding:7px 12px;background:#f3f7f7;margin:15px 0 20px}.impulse-system>div:first-child{font-size:12px;line-height:1.7}.impulse-system strong{display:block}.impulse-system [data-formula]{display:block;margin-top:5px}.impulse-system>.plot{width:130px;flex-shrink:0}.impulse-system label{display:flex;align-items:center;gap:8px;font-size:12px;flex-wrap:wrap}.impulse-system input{width:105px;accent-color:var(--blue)}.impulse-flow{display:grid;grid-template-columns:minmax(135px,1fr) minmax(350px,2.5fr) minmax(155px,1.1fr);gap:20px;align-items:center}.impulse-summary h3{font-size:14px;margin:0 0 9px}.impulse-summary p{font-size:12px;line-height:1.7}.impulse-summary .flow-word{display:block;color:#637d89;font-size:12px;margin:12px 0}.impulse-rows{border-left:1px solid var(--line);border-right:1px solid var(--line);padding:0 12px}.impulse-row{display:grid;grid-template-columns:minmax(0,1fr) 29px minmax(0,1fr);gap:5px;align-items:end;margin:0 0 15px}.impulse-row:last-child{margin-bottom:0}.impulse-row label{display:flex;align-items:center;gap:5px;font-size:12px;color:var(--row);font-weight:600}.impulse-row input{width:70px;min-width:30px;flex:1;accent-color:var(--row)}.impulse-row output{min-width:26px;text-align:right}.term-label{font-size:12px;margin-top:5px;color:var(--row)}.response-term{margin-bottom:0}.system-arrow{align-self:center;text-align:center;color:#81979f;font-size:12px;padding-top:24px}.output-picks{display:flex;gap:4px;justify-content:space-between}.output-picks button{background:white;border:1px solid #d3dfe2;padding:5px;min-width:31px;color:#405b65;line-height:1.7;font-size:12px}.output-picks button small{display:block;font-size:9px;color:var(--muted)}.output-picks button[aria-pressed=true]{border-color:var(--blue);background:#edf6f8}.colored-sum{font-variant-numeric:tabular-nums;font-size:14px;line-height:1.7}.impulse-summary .sum-label{margin:14px 0 5px;font-size:11px}.impulse-flow .plot svg text{font-size:10px}
@media(max-width:1100px) and (min-width:821px){.impulse-flow{grid-template-columns:minmax(120px,1fr) minmax(250px,2fr) minmax(120px,1fr);gap:10px}.impulse-rows{padding:0 6px}.impulse-row{grid-template-columns:minmax(0,1fr) 15px minmax(0,1fr);gap:1px}.impulse-row label{font-size:10px}.impulse-row input{width:35px}.impulse-row output{min-width:18px}.impulse-system{gap:10px}.impulse-system>.plot{width:95px}}
@media(max-width:640px){.impulse-system{margin:10px 0 14px;flex-wrap:wrap;gap:2px 13px;padding:9px}.impulse-system>div:first-child{flex:1;min-width:210px}.impulse-system [data-formula]{font-size:11px}.impulse-system>.plot{width:80px}.impulse-system label{flex:1;min-width:160px}.impulse-flow{display:flex;flex-direction:column;gap:10px;align-items:stretch}.impulse-summary{display:grid;grid-template-columns:1fr 1.4fr;gap:0 12px;align-items:center}.impulse-summary h3{grid-column:1;font-size:13px;margin:0}.impulse-summary>.plot{grid-column:2;grid-row:1/4}.impulse-summary p{margin:5px 0;font-size:11px}.impulse-summary .flow-word{margin:1px 0;font-size:11px}.input-summary .flow-word{font-size:0}.input-summary .flow-word:after{content:'분해 ↓';font-size:11px}.impulse-rows{border-left:0;border-right:0;border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:9px 0}.impulse-row{margin-bottom:8px;grid-template-columns:minmax(0,1fr) 28px minmax(0,1fr);gap:10px}.impulse-row label{font-size:12px}.impulse-row input{width:60px}.term-label{font-size:11px}.system-arrow{font-size:11px}.output-summary>.flow-word{display:none}.output-summary>.plot{grid-row:1/3}.output-picks{grid-column:1;margin:8px 0}.output-summary .sum-label{grid-column:1;font-size:10px;margin:0}.colored-sum{grid-column:2;font-size:13px}.impulse-flow+.figure-reading{font-size:12px;line-height:1.7}}
.sr-only{position:absolute!important;width:1px!important;height:1px!important;padding:0!important;margin:-1px!important;overflow:hidden!important;clip:rect(0,0,0,0)!important;white-space:nowrap!important;border:0!important}.impulse-system label{margin-top:7px}.impulse-row label .term-label{margin:0;font-size:11px;flex-shrink:0}.impulse-row .response-term{min-height:26px;display:flex;align-items:center;margin:0}.impulse-row .system-arrow{font-size:16px;padding:0;color:var(--row)}
@media(max-width:640px){[data-figure$="/impulse-response"] .figure-subtitle{margin-bottom:8px}.impulse-system>div:first-child{min-width:190px}.impulse-system label{min-width:0;margin-top:5px}.impulse-system{flex-wrap:nowrap}.impulse-system>.plot{width:93px}.impulse-row label .term-label{font-size:10px}.impulse-row input{min-width:20px;width:34px}.impulse-row{gap:7px;grid-template-columns:minmax(0,1fr) 20px minmax(0,1fr)}.impulse-flow+.figure-reading{min-height:0;font-size:11px}.impulse-summary .flow-word{margin:0}}

.figure-todo{margin:var(--figure-gap) 0;padding:12px 14px;border:1px dashed #9fb3bd;border-radius:4px;background:#f7fafb;color:#51656f;font-size:14px;line-height:1.55}.figure-todo strong{color:#36535f}
.table-scroll{overflow-x:auto;margin:20px 0}article table{border-collapse:collapse;font-size:15px;line-height:1.6}article th,article td{padding:7px 14px 7px 0;border-bottom:1px solid var(--line);text-align:left;vertical-align:middle}article th{font-weight:650;border-bottom:2px solid #9fb3bd}.table-scroll th,.table-scroll td{white-space:nowrap}
/* A figure is its own block in the reading column: its rules run exactly under the text's edges, with --figure-gap above
   and below. An interactive figure and the credit line under it form one block. A static figure takes the same frame (the
   rules override the inline margin and max-width in the chapter source); its drawing keeps its own size inside. */
.reading-width .concept-figure:has(+.figure-credit){margin-bottom:0;border-bottom:0}.reading-width .concept-figure+.figure-credit{margin:0 0 var(--figure-gap);padding:0 0 14px;border-bottom:1px solid var(--line)}
.reading-width article figure{margin:var(--figure-gap) 0!important;max-width:none!important;padding:19px 0 14px;border-top:2px solid var(--figure-rule);border-bottom:1px solid var(--line)}.reading-width article figure:is(.static-figure,.inline-figure)>svg{max-width:560px;margin:0 auto}
@media(max-width:540px){.reading-width article figure{padding-top:14px}}
/* Narrow phones: 14 px side padding keeps a 292 px column at 320 px (sampling's option row needs 288 px). */
@media(max-width:360px){main{padding-left:14px;padding-right:14px}.book-sidebar{padding:0 14px}}
/* vector-projection's 19 px title needs 281 px; on a 280 px column it took a second line and the figure reached 861 px.
   Since the 14 px phone padding the column is 292 px at 320 px; the rule still covers columns below 281 px (viewports under 309 px). */
@media(max-width:340px){.reading-width [data-figure$="/vector-projection"] .g-title{font-size:18px}}