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1fr;margin-bottom:6rem;padding-bottom:2rem;padding-top:2rem}[data-course-shell=frontend] .policy-callout h2{font-size:1.8rem}[data-course-shell=frontend] .policy-callout p{line-height:1.65;margin-bottom:0}[data-course-shell=frontend] .site-footer{align-items:center;background:var(--ink);color:var(--paper-strong);display:flex;justify-content:space-between;min-height:8rem;padding:2rem max(2rem,calc((100vw - 84rem) / 2))}[data-course-shell=frontend] .site-footer a,[data-course-shell=frontend] .site-footer p{font-family:var(--font-mono);font-size:.74rem}@media (max-width:960px){[data-course-shell=frontend] .hero{grid-template-columns:1fr;gap:4rem}[data-course-shell=frontend] .runtime-stack{margin-left:0;max-width:36rem}[data-course-shell=frontend] .curriculum-layout{grid-template-columns:minmax(0,1fr)}[data-course-shell=frontend] .toc{background:var(--paper);border-bottom:1px solid var(--ink);display:flex;gap:.25rem;max-height:none;overflow-x:auto;padding:.5rem 0;position:sticky;top:4.2rem;z-index:30}[data-course-shell=frontend] .toc>p{clip:rect(0 0 0 0);height:1px;overflow:hidden;position:absolute;width:1px}[data-course-shell=frontend] .toc ol{display:flex;margin:0}[data-course-shell=frontend] .toc li{flex:0 0 auto}[data-course-shell=frontend] .toc a{border:1px solid var(--line);display:block;min-height:2.75rem;padding:.75rem;white-space:nowrap}[data-course-shell=frontend] .toc a span{margin-right:.45rem}}@media (max-width:720px){[data-course-shell=frontend] .site-header{grid-template-columns:1fr auto;padding:0 1rem}[data-course-shell=frontend] .header-meta{display:none}[data-course-shell=frontend] .hero{min-height:auto;padding:5rem 1.25rem}[data-course-shell=frontend] .hero h1{font-size:clamp(3.6rem,19vw,6rem)}[data-course-shell=frontend] .architecture-panel,[data-course-shell=frontend] .capstone-intro,[data-course-shell=frontend] .evidence-strip,[data-course-shell=frontend] .glossary-heading,[data-course-shell=frontend] .trace-overview{grid-template-columns:1fr}[data-course-shell=frontend] .trace-rail{grid-template-columns:repeat(2,1fr)}[data-course-shell=frontend] .trace-rail li:nth-child(3n){border-right:0}[data-course-shell=frontend] .trace-rail li:nth-child(2n){border-right:1px solid var(--ink)}[data-course-shell=frontend] .trace-rail li:nth-child(n+3){border-bottom:1px solid var(--ink)}[data-course-shell=frontend] .evidence-strip dl{grid-template-columns:1fr}[data-course-shell=frontend] .curriculum-layout{padding:4rem 1rem}[data-course-shell=frontend] .curriculum-heading{grid-template-columns:1fr}[data-course-shell=frontend] .module-card>summary{gap:.6rem;grid-template-columns:3rem 1fr 1.5rem}[data-course-shell=frontend] .module-duration{display:none}[data-course-shell=frontend] .module-body{padding:1rem}[data-course-shell=frontend] .lab-heading-row,[data-course-shell=frontend] .lesson-heading{align-items:start;flex-direction:column}[data-course-shell=frontend] .lab-layout{grid-template-columns:1fr}[data-course-shell=frontend] .lab-selector{border-bottom:1px solid var(--line-dark);border-right:0;display:flex;max-height:none;overflow-x:auto}[data-course-shell=frontend] .lab-selector button{border-bottom:0;border-right:1px solid var(--line-dark);flex:0 0 10rem;min-height:4.6rem}[data-course-shell=frontend] .glossary-grid{grid-template-columns:1fr}[data-course-shell=frontend] .glossary-grid>div,[data-course-shell=frontend] .glossary-grid>div:nth-child(3n),[data-course-shell=frontend] .glossary-grid>div:nth-last-child(-n+3){border-bottom:0;border-left:1px solid var(--line);border-right:1px solid var(--line)}[data-course-shell=frontend] .glossary-grid>div:last-child{border-bottom:1px solid var(--line)}}@media (max-width:420px){[data-course-shell=frontend] .architecture-panel,[data-course-shell=frontend] .capstone-shell,[data-course-shell=frontend] .evidence-strip,[data-course-shell=frontend] .failure-lab,[data-course-shell=frontend] .glossary,[data-course-shell=frontend] .policy-callout,[data-course-shell=frontend] .trace-overview{padding-left:1rem;padding-right:1rem}[data-course-shell=frontend] .hero-actions{align-items:stretch;flex-direction:column}[data-course-shell=frontend] .hero-actions .button{width:100%}[data-course-shell=frontend] .runtime-stack div{padding:1rem}[data-course-shell=frontend] .trace-rail{grid-template-columns:1fr}[data-course-shell=frontend] .trace-rail li,[data-course-shell=frontend] .trace-rail li:nth-child(2n),[data-course-shell=frontend] .trace-rail li:nth-child(3n){border-bottom:0;border-right:1px solid var(--ink)}[data-course-shell=frontend] .trace-rail li:last-child{border-bottom:1px solid var(--ink)}[data-course-shell=frontend] .module-summary-copy strong{font-size:1.25rem}[data-course-shell=frontend] .module-summary-copy span{display:none}[data-course-shell=frontend] .module-outcome{margin-left:-1rem;margin-right:-1rem}[data-course-shell=frontend] .lesson-body{font-size:.94rem}[data-course-shell=frontend] .policy-callout{grid-template-columns:1fr}[data-course-shell=frontend] .site-footer{align-items:start;flex-direction:column}}@media (prefers-reduced-motion:reduce){[data-course-shell=frontend]{scroll-behavior:auto}[data-course-shell=frontend] *,[data-course-shell=frontend] :after,[data-course-shell=frontend] :before{animation-duration:.01ms!important;animation-iteration-count:1!important;scroll-behavior:auto!important;transition-duration:.01ms!important}}@media print{[data-course-shell=frontend] .code-header button,[data-course-shell=frontend] .hero-actions,[data-course-shell=frontend] .locale-switch,[data-course-shell=frontend] .site-header,[data-course-shell=frontend] .toc{display:none!important}[data-course-shell=frontend] .hero{background:white;color:black;min-height:auto}[data-course-shell=frontend] .hero h1 span{color:black}[data-course-shell=frontend] .module-card{-moz-column-break-inside:avoid;break-inside:avoid}[data-course-shell=frontend] .module-card>.module-body{display:block}}[data-course-shell=postgres]{--ink:#18201e;--ink-2:#34403c;--paper:#f3f0e8;--paper-2:#e8e4da;--white:#fbfaf6;--night:#12231f;--night-2:#19342d;--mint:#9fe3c0;--orange:#f06a3a;--yellow:#e8d878;--blue:#a9c8f5;--line:rgba(24,32,30,0.18);--line-dark:rgba(255,255,255,0.18);--shadow:0 18px 60px rgba(26,36,32,0.1);--radius:2px}[data-course-shell=postgres] *{box-sizing:border-box}[data-course-shell=postgres]{scroll-behavior:smooth;scroll-padding-top:86px;margin:0;background:var(--paper);color:var(--ink);font-family:Inter,ui-sans-serif,-apple-system,BlinkMacSystemFont,Segoe UI,Apple SD Gothic Neo,Noto Sans KR,sans-serif;line-height:1.55;text-rendering:optimizeLegibility}[data-course-shell=postgres] button,[data-course-shell=postgres] input{font:inherit}[data-course-shell=postgres] a,[data-course-shell=postgres] button{-webkit-tap-highlight-color:transparent}[data-course-shell=postgres] a{color:inherit;text-decoration:none}[data-course-shell=postgres] a:focus-visible,[data-course-shell=postgres] button:focus-visible,[data-course-shell=postgres] input:focus-visible,[data-course-shell=postgres] pre:focus-visible,[data-course-shell=postgres] summary:focus-visible{outline:3px solid var(--orange);outline-offset:3px}[data-course-shell=postgres] ::-moz-selection{background:var(--yellow);color:var(--ink)}[data-course-shell=postgres] ::selection{background:var(--yellow);color:var(--ink)}[data-course-shell=postgres] .site-shell{min-width:0;overflow:clip}[data-course-shell=postgres] .skip-link{position:fixed;z-index:1000;left:16px;top:10px;padding:10px 14px;background:var(--white);border:2px solid var(--ink);transform:translateY(-160%);transition:transform .16s ease}[data-course-shell=postgres] .skip-link:focus{transform:translateY(0)}[data-course-shell=postgres] .topbar{position:sticky;z-index:50;top:0;display:flex;align-items:center;justify-content:space-between;min-height:68px;padding:0 3.2vw;border-bottom:1px solid var(--line-dark);background:rgba(18,35,31,.96);color:var(--white);backdrop-filter:blur(14px)}[data-course-shell=postgres] .language-switch,[data-course-shell=postgres] .topbar-meta,[data-course-shell=postgres] .version-chip,[data-course-shell=postgres] .wordmark,[data-course-shell=postgres] .wordmark-mark{display:flex;align-items:center}[data-course-shell=postgres] .wordmark{gap:11px;font-size:.88rem;font-weight:800;letter-spacing:-.02em}[data-course-shell=postgres] .wordmark-mark{justify-content:center;width:32px;height:32px;border:1px solid;border-radius:50%;font-family:var(--font-mono,ui-monospace),monospace;font-size:.68rem;letter-spacing:-.04em}[data-course-shell=postgres] .topbar-meta{gap:24px}[data-course-shell=postgres] .version-chip{gap:8px;color:rgba(255,255,255,.7);font-family:var(--font-mono,ui-monospace),monospace;font-size:.68rem;letter-spacing:.06em}[data-course-shell=postgres] .status-dot{width:7px;height:7px;border-radius:50%;background:var(--mint);box-shadow:0 0 0 4px rgba(159,227,192,.12)}[data-course-shell=postgres] .language-switch{overflow:hidden;border:1px solid rgba(255,255,255,.3)}[data-course-shell=postgres] .language-switch button{min-width:42px;min-height:34px;border:0;background:transparent;color:rgba(255,255,255,.64);cursor:pointer;font-family:var(--font-mono,ui-monospace),monospace;font-size:.7rem;font-weight:800}[data-course-shell=postgres] .language-switch button+button{border-left:1px solid rgba(255,255,255,.3)}[data-course-shell=postgres] .language-switch button[aria-pressed=true]{background:var(--mint);color:var(--night)}[data-course-shell=postgres] .hero{position:relative;display:grid;grid-template-columns:minmax(0,1.1fr) minmax(380px,.9fr);gap:clamp(40px,7vw,110px);min-height:min(780px,calc(100vh - 68px));padding:clamp(76px,10vw,138px) 6vw 48px;overflow:hidden;background:var(--night);color:var(--white)}[data-course-shell=postgres] .hero-grid{position:absolute;inset:0;opacity:.12;background-image:linear-gradient(rgba(255,255,255,.22) 1px,transparent 0),linear-gradient(90deg,rgba(255,255,255,.22) 1px,transparent 0);background-size:48px 48px;-webkit-mask-image:linear-gradient(180deg,black,transparent 88%);mask-image:linear-gradient(180deg,black,transparent 88%);pointer-events:none}[data-course-shell=postgres] .hero-copy,[data-course-shell=postgres] .hero-stats,[data-course-shell=postgres] .hero-terminal{position:relative;z-index:1}[data-course-shell=postgres] .hero-copy{align-self:center;max-width:760px}[data-course-shell=postgres] .eyebrow,[data-course-shell=postgres] .section-index{margin:0 0 20px;color:var(--orange);font-family:var(--font-mono,ui-monospace),monospace;font-size:.72rem;font-weight:800;letter-spacing:.1em;text-transform:uppercase}[data-course-shell=postgres] .eyebrow span{display:inline-flex;align-items:center;justify-content:center;width:30px;height:30px;margin-right:12px;border:1px solid;border-radius:50%}[data-course-shell=postgres] .hero h1{margin:0;font-size:clamp(3.6rem,8vw,8.2rem);font-weight:520;letter-spacing:-.075em;line-height:.86}[data-course-shell=postgres] .hero h1 span,[data-course-shell=postgres] .hero h1 strong{display:block}[data-course-shell=postgres] .hero h1 strong{color:var(--mint);font-weight:820}[data-course-shell=postgres] .hero-deck{max-width:700px;margin:36px 0 0;color:rgba(255,255,255,.72);font-size:clamp(1rem,1.5vw,1.25rem);line-height:1.75}[data-course-shell=postgres] .evidence-inline{display:inline-block;margin-right:10px;padding:3px 6px;border:1px solid;color:var(--orange);font-family:var(--font-mono,ui-monospace),monospace;font-size:.58rem;font-weight:900;letter-spacing:.05em;vertical-align:.18em;white-space:nowrap}[data-course-shell=postgres] .hero-actions{display:flex;flex-wrap:wrap;gap:12px;margin-top:40px}[data-course-shell=postgres] .button{display:inline-flex;align-items:center;justify-content:space-between;gap:28px;min-width:190px;min-height:52px;padding:0 18px;border:1px solid var(--mint);font-size:.84rem;font-weight:780;transition:background .16s ease,color .16s ease,transform .16s ease}[data-course-shell=postgres] .button:hover{transform:translateY(-2px)}[data-course-shell=postgres] .button-primary{background:var(--mint);color:var(--night)}[data-course-shell=postgres] .button-primary:hover{background:var(--white)}[data-course-shell=postgres] .button-secondary{color:var(--mint)}[data-course-shell=postgres] .button-secondary:hover{background:rgba(159,227,192,.1)}[data-course-shell=postgres] .hero-terminal{align-self:center;border:1px solid rgba(159,227,192,.34);background:rgba(5,16,13,.72);box-shadow:30px 30px 0 rgba(159,227,192,.07);transform:translateY(14px)}[data-course-shell=postgres] .terminal-bar{display:flex;align-items:center;gap:6px;min-height:40px;padding:0 14px;border-bottom:1px solid rgba(159,227,192,.2)}[data-course-shell=postgres] .terminal-bar span{width:8px;height:8px;border-radius:50%;background:rgba(255,255,255,.26)}[data-course-shell=postgres] .terminal-bar span:first-child{background:var(--orange)}[data-course-shell=postgres] .terminal-bar b{margin-left:auto;color:rgba(255,255,255,.44);font-family:var(--font-mono,ui-monospace),monospace;font-size:.62rem;font-weight:500}[data-course-shell=postgres] .hero-terminal pre{margin:0;padding:clamp(22px,3vw,36px);overflow:auto;color:#c9eadb;font-family:var(--font-mono,ui-monospace),monospace;font-size:clamp(.7rem,1vw,.86rem);line-height:1.9}[data-course-shell=postgres] .trace-row{display:grid;grid-template-columns:repeat(7,auto);align-items:center;justify-content:space-between;gap:8px;padding:14px 18px;border-top:1px solid rgba(159,227,192,.2);color:rgba(255,255,255,.58);font-family:var(--font-mono,ui-monospace),monospace;font-size:.62rem;text-transform:uppercase}[data-course-shell=postgres] .trace-row i{color:var(--orange);font-style:normal}[data-course-shell=postgres] .hero-stats{display:grid;grid-column:1/-1;grid-template-columns:repeat(3,minmax(0,1fr));align-self:end;margin:30px 0 0;border-top:1px solid var(--line-dark)}[data-course-shell=postgres] .hero-stats div{display:flex;align-items:baseline;gap:14px;padding:28px 0 0}[data-course-shell=postgres] .hero-stats div+div{padding-left:34px;border-left:1px solid var(--line-dark)}[data-course-shell=postgres] .hero-stats dt{color:var(--mint);font-family:var(--font-mono,ui-monospace),monospace;font-size:clamp(1.7rem,3vw,2.5rem);font-weight:760}[data-course-shell=postgres] .hero-stats dd{margin:0;color:rgba(255,255,255,.52);font-size:.75rem;text-transform:uppercase}[data-course-shell=postgres] .evidence-strip{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));border-bottom:1px solid var(--line);background:var(--white)}[data-course-shell=postgres] .evidence-card{min-height:164px;padding:26px 2.4vw;border-right:1px solid var(--line)}[data-course-shell=postgres] .evidence-card:last-child{border-right:0}[data-course-shell=postgres] .evidence-card>span{color:rgba(24,32,30,.35);font-family:var(--font-mono,ui-monospace),monospace;font-size:.66rem}[data-course-shell=postgres] .evidence-card h2{margin:20px 0 8px;font-family:var(--font-mono,ui-monospace),monospace;font-size:.78rem;letter-spacing:-.02em}[data-course-shell=postgres] .evidence-card p{max-width:290px;margin:0;color:var(--ink-2);font-size:.75rem}[data-course-shell=postgres] .evidence-spec{box-shadow:inset 0 4px 0 var(--blue)}[data-course-shell=postgres] .evidence-verified-behavior{box-shadow:inset 0 4px 0 var(--mint)}[data-course-shell=postgres] .evidence-recommended-practice{box-shadow:inset 0 4px 0 var(--yellow)}[data-course-shell=postgres] .evidence-project-policy{box-shadow:inset 0 4px 0 var(--orange)}[data-course-shell=postgres] .course{display:grid;grid-template-columns:minmax(280px,360px) minmax(0,1fr);max-width:1540px;margin:0 auto;border-right:1px solid var(--line);border-left:1px solid var(--line)}[data-course-shell=postgres] .course-nav{position:sticky;top:68px;align-self:start;max-height:calc(100vh - 68px);padding:34px 26px 24px;overflow:auto;border-right:1px solid var(--line);background:var(--paper-2)}[data-course-shell=postgres] .nav-heading{display:flex;align-items:end;justify-content:space-between;gap:24px}[data-course-shell=postgres] .nav-heading .section-index{margin-bottom:5px}[data-course-shell=postgres] .nav-heading h2{margin:0;font-size:1.15rem;letter-spacing:-.04em}[data-course-shell=postgres] .nav-heading>span{color:var(--ink-2);font-family:var(--font-mono,ui-monospace),monospace;font-size:.72rem}[data-course-shell=postgres] .progress-track{height:3px;margin:18px 0 26px;overflow:hidden;background:rgba(24,32,30,.14)}[data-course-shell=postgres] .progress-track span{display:block;height:100%;background:var(--orange);transition:width .24s ease}[data-course-shell=postgres] .search-field{display:block;margin-bottom:15px}[data-course-shell=postgres] .search-field span{display:block;margin-bottom:7px;color:var(--ink-2);font-family:var(--font-mono,ui-monospace),monospace;font-size:.62rem;font-weight:800;text-transform:uppercase}[data-course-shell=postgres] .search-field input{width:100%;min-height:42px;padding:0 12px;border:1px solid var(--line);border-radius:0;background:rgba(255,255,255,.45);color:var(--ink);font-size:.78rem}[data-course-shell=postgres] .module-link{display:grid;grid-template-columns:42px minmax(0,1fr) 18px;gap:10px;align-items:start;padding:14px 10px;border-top:1px solid var(--line);transition:background .13s ease,transform .13s ease}[data-course-shell=postgres] .module-link:last-child{border-bottom:1px solid var(--line)}[data-course-shell=postgres] .module-link:hover{background:rgba(255,255,255,.42);transform:translateX(3px)}[data-course-shell=postgres] .module-link.active{background:var(--night);color:var(--white)}[data-course-shell=postgres] .module-link>span:first-child{color:var(--orange);font-family:var(--font-mono,ui-monospace),monospace;font-size:.7rem;font-weight:800}[data-course-shell=postgres] .module-link b,[data-course-shell=postgres] .module-link small{display:block}[data-course-shell=postgres] .module-link b{font-size:.76rem;letter-spacing:-.02em}[data-course-shell=postgres] .module-link small{margin-top:3px;color:var(--ink-2);font-size:.64rem;line-height:1.4}[data-course-shell=postgres] .module-link.active small{color:rgba(255,255,255,.55)}[data-course-shell=postgres] .module-link i{color:var(--mint);font-style:normal}[data-course-shell=postgres] .empty-state{padding:30px 10px;color:var(--ink-2);font-size:.8rem}[data-course-shell=postgres] .reset-button{width:100%;margin-top:16px;min-height:40px;border:1px solid var(--line);background:transparent;color:var(--ink-2);cursor:pointer;font-family:var(--font-mono,ui-monospace),monospace;font-size:.62rem;font-weight:800;text-transform:uppercase}[data-course-shell=postgres] .reset-button:hover:not(:disabled){border-color:var(--orange);color:var(--orange)}[data-course-shell=postgres] .reset-button:disabled{cursor:not-allowed;opacity:.4}[data-course-shell=postgres] .module{min-width:0;padding:clamp(36px,5vw,76px);background:var(--white)}[data-course-shell=postgres] .module-header{display:grid;grid-template-columns:auto minmax(0,1fr) auto;gap:28px;align-items:start;padding-bottom:40px;border-bottom:2px solid var(--ink)}[data-course-shell=postgres] .module-number{display:flex;align-items:center;justify-content:center;width:64px;height:64px;border:2px solid var(--ink);border-radius:50%;color:var(--orange);font-family:var(--font-mono,ui-monospace),monospace;font-weight:900}[data-course-shell=postgres] .module-title p{margin:0 0 7px;color:var(--orange);font-family:var(--font-mono,ui-monospace),monospace;font-size:.62rem;font-weight:900;letter-spacing:.08em}[data-course-shell=postgres] .module-title h2{margin:0;font-size:clamp(2rem,4vw,4.5rem);letter-spacing:-.07em;line-height:.98}[data-course-shell=postgres] .module-title>span{display:block;max-width:690px;margin-top:15px;color:var(--ink-2);font-size:.92rem}[data-course-shell=postgres] .complete-button{display:flex;align-items:center;gap:8px;min-height:42px;padding:0 12px;border:1px solid var(--line);background:transparent;color:var(--ink-2);cursor:pointer;font-size:.68rem;font-weight:800}[data-course-shell=postgres] .complete-button.is-complete,[data-course-shell=postgres] .complete-button:hover{border-color:var(--night);background:var(--night);color:var(--mint)}[data-course-shell=postgres] .module-meta{display:grid;grid-template-columns:repeat(3,1fr);margin-bottom:48px;border-bottom:1px solid var(--line)}[data-course-shell=postgres] .module-meta>div{display:flex;gap:12px;align-items:baseline;min-height:78px;padding:22px 20px 18px 0}[data-course-shell=postgres] .module-meta>div+div{padding-left:20px;border-left:1px solid var(--line)}[data-course-shell=postgres] .module-meta span{font-family:var(--font-mono,ui-monospace),monospace;font-size:1.6rem;font-weight:800}[data-course-shell=postgres] .module-meta p{margin:0;color:var(--ink-2);font-size:.65rem;text-transform:uppercase}[data-course-shell=postgres] .concept-block{display:grid;grid-template-columns:180px minmax(0,1fr);gap:30px;align-items:start;margin-bottom:46px}[data-course-shell=postgres] .concept-block h3{margin:4px 0 0;font-family:var(--font-mono,ui-monospace),monospace;font-size:.68rem;text-transform:uppercase}[data-course-shell=postgres] .concept-block ul{display:flex;flex-wrap:wrap;gap:7px;margin:0;padding:0;list-style:none}[data-course-shell=postgres] .concept-block li{padding:7px 10px;border:1px solid var(--line);background:var(--paper);font-family:var(--font-mono,ui-monospace),monospace;font-size:.64rem}[data-course-shell=postgres] .section-list{border-top:2px solid var(--ink)}[data-course-shell=postgres] .learning-section{border-bottom:1px solid var(--line)}[data-course-shell=postgres] .learning-section summary{display:grid;grid-template-columns:42px minmax(0,1fr) auto 22px;gap:16px;align-items:center;min-height:80px;padding:14px 8px;cursor:pointer;list-style:none}[data-course-shell=postgres] .learning-section summary::-webkit-details-marker,[data-course-shell=postgres] .quiz-item summary::-webkit-details-marker{display:none}[data-course-shell=postgres] .learning-section summary:hover{background:var(--paper)}[data-course-shell=postgres] .learning-section summary>span{color:rgba(24,32,30,.4);font-family:var(--font-mono,ui-monospace),monospace;font-size:.68rem}[data-course-shell=postgres] .learning-section summary h3{margin:0;font-size:.92rem;letter-spacing:-.025em}[data-course-shell=postgres] .learning-section summary i{font-style:normal;transition:transform .16s ease}[data-course-shell=postgres] .learning-section[open] summary i{transform:rotate(45deg)}[data-course-shell=postgres] .evidence-badge{padding:4px 7px;border:1px solid var(--line);font-family:var(--font-mono,ui-monospace),monospace;font-size:.51rem;letter-spacing:.02em}[data-course-shell=postgres] .badge-spec{background:var(--blue)}[data-course-shell=postgres] .badge-verified-behavior{background:var(--mint)}[data-course-shell=postgres] .badge-recommended-practice{background:var(--yellow)}[data-course-shell=postgres] .badge-project-policy{background:#f7b297}[data-course-shell=postgres] .section-body{padding:0 42px 30px 66px}[data-course-shell=postgres] .section-body>p{max-width:850px;margin:0;color:var(--ink-2);font-size:.92rem;line-height:1.8;white-space:pre-line}[data-course-shell=postgres] .section-body ul{max-width:850px;margin:18px 0 0;padding-left:20px;color:var(--ink-2);font-size:.82rem}[data-course-shell=postgres] .section-body li+li{margin-top:7px}[data-course-shell=postgres] .section-body pre{max-width:100%;margin:24px 0 0;padding:24px;overflow:auto;border-left:4px solid var(--mint);background:var(--night);color:#d6f4e5;font-family:var(--font-mono,ui-monospace),monospace;font-size:.74rem;line-height:1.8}[data-course-shell=postgres] .quiz-block{margin-top:66px;border-top:2px solid var(--ink);border-bottom:2px solid var(--ink)}[data-course-shell=postgres] .quiz-heading{display:flex;align-items:baseline;gap:22px;padding:28px 8px 20px}[data-course-shell=postgres] .quiz-heading .section-index,[data-course-shell=postgres] .quiz-heading h3{margin:0}[data-course-shell=postgres] .quiz-heading h3{font-size:1.5rem;letter-spacing:-.05em}[data-course-shell=postgres] .quiz-item{border-top:1px solid var(--line)}[data-course-shell=postgres] .quiz-item summary{display:grid;grid-template-columns:46px minmax(0,1fr) auto;gap:18px;align-items:center;min-height:66px;padding:12px 8px;cursor:pointer;font-size:.84rem;font-weight:700;list-style:none}[data-course-shell=postgres] .quiz-item summary>b,[data-course-shell=postgres] .quiz-item summary>span{color:var(--orange);font-family:var(--font-mono,ui-monospace),monospace;font-size:.58rem}[data-course-shell=postgres] .quiz-item p{display:grid;grid-template-columns:110px minmax(0,1fr);gap:18px;margin:0;padding:20px 8px 28px 72px;background:var(--paper);color:var(--ink-2);font-size:.82rem}[data-course-shell=postgres] .quiz-item p strong{color:var(--ink);font-family:var(--font-mono,ui-monospace),monospace;font-size:.6rem;text-transform:uppercase}[data-course-shell=postgres] .module-pager{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-top:40px}[data-course-shell=postgres] .module-pager a{display:flex;flex-direction:column;gap:5px;padding:16px;border:1px solid var(--line);transition:background .13s ease}[data-course-shell=postgres] .module-pager a:hover{background:var(--paper)}[data-course-shell=postgres] .module-pager a.next{text-align:right}[data-course-shell=postgres] .module-pager span{color:var(--orange);font-family:var(--font-mono,ui-monospace),monospace;font-size:.6rem;font-weight:800;text-transform:uppercase}[data-course-shell=postgres] .module-pager b{font-size:.75rem}[data-course-shell=postgres] .section-lead{display:grid;grid-template-columns:170px minmax(260px,.8fr) minmax(300px,.9fr);gap:36px;align-items:start;max-width:1540px;margin:0 auto;padding:76px 6vw 46px}[data-course-shell=postgres] .section-lead .section-index{margin:7px 0 0}[data-course-shell=postgres] .section-lead h2{margin:0;font-size:clamp(2.2rem,4vw,4.7rem);letter-spacing:-.07em;line-height:.95}[data-course-shell=postgres] .section-lead>p:last-child{margin:3px 0 0;color:var(--ink-2);font-size:.92rem;line-height:1.75}[data-course-shell=postgres] .lab-section{background:var(--night);color:var(--white)}[data-course-shell=postgres] .dark-lead>p:last-child{color:rgba(255,255,255,.66)}[data-course-shell=postgres] .lab-layout{display:grid;grid-template-columns:minmax(0,1fr) minmax(420px,.8fr);max-width:1540px;margin:0 auto;border-top:1px solid var(--line-dark);border-right:1px solid var(--line-dark);border-left:1px solid var(--line-dark)}[data-course-shell=postgres] .runbook{padding:44px 4vw 56px;border-right:1px solid var(--line-dark)}[data-course-shell=postgres] .runbook h3{margin:0;font-size:1.15rem}[data-course-shell=postgres] .runbook>p{margin:8px 0 28px;color:rgba(255,255,255,.54);font-size:.76rem}[data-course-shell=postgres] .runbook ol{margin:0;padding:0;border-top:1px solid var(--line-dark);list-style:none}[data-course-shell=postgres] .runbook li{display:grid;grid-template-columns:42px minmax(0,1fr) auto;gap:18px;align-items:center;min-height:86px;border-bottom:1px solid var(--line-dark)}[data-course-shell=postgres] .runbook li>span{color:var(--orange);font-family:var(--font-mono,ui-monospace),monospace;font-size:.66rem;font-weight:900}[data-course-shell=postgres] .runbook li p{margin:0 0 3px;font-size:.74rem}[data-course-shell=postgres] .runbook li code{color:var(--mint);font-family:var(--font-mono,ui-monospace),monospace;font-size:.68rem}[data-course-shell=postgres] .runbook button{min-width:54px;min-height:32px;border:1px solid rgba(159,227,192,.35);background:transparent;color:var(--mint);cursor:pointer;font-family:var(--font-mono,ui-monospace),monospace;font-size:.54rem;font-weight:900}[data-course-shell=postgres] .runbook button:hover{background:var(--mint);color:var(--night)}[data-course-shell=postgres] .architecture{display:flex;flex-direction:column;justify-content:center;padding:44px 3vw 56px;background:rgba(255,255,255,.025)}[data-course-shell=postgres] .arch-label{display:flex;align-items:baseline;justify-content:space-between;gap:20px;padding-bottom:18px;border-bottom:1px solid var(--line-dark)}[data-course-shell=postgres] .arch-label span{color:var(--orange);font-family:var(--font-mono,ui-monospace),monospace;font-size:.58rem;font-weight:900}[data-course-shell=postgres] .arch-label b{color:rgba(255,255,255,.48);font-size:.66rem}[data-course-shell=postgres] .arch-flow{display:grid;grid-template-columns:1fr auto 1fr auto 1fr;gap:12px;align-items:center;padding:42px 0}[data-course-shell=postgres] .arch-flow>div{display:flex;flex-direction:column;justify-content:center;min-height:132px;padding:16px;border:1px solid rgba(255,255,255,.24)}[data-course-shell=postgres] .arch-flow>div span{color:var(--orange);font-family:var(--font-mono,ui-monospace),monospace;font-size:.52rem;font-weight:900}[data-course-shell=postgres] .arch-flow>div b{margin-top:8px;font-size:.78rem}[data-course-shell=postgres] .arch-flow>div small{margin-top:4px;color:rgba(255,255,255,.48);font-size:.58rem}[data-course-shell=postgres] .arch-flow .arch-db{border-color:var(--mint);background:rgba(159,227,192,.08)}[data-course-shell=postgres] .arch-arrow{color:var(--mint)}[data-course-shell=postgres] .arch-bottom{display:grid;grid-template-columns:repeat(4,1fr);border-top:1px solid var(--line-dark);border-bottom:1px solid var(--line-dark)}[data-course-shell=postgres] .arch-bottom span{padding:11px 4px;border-right:1px solid var(--line-dark);color:rgba(255,255,255,.48);font-family:var(--font-mono,ui-monospace),monospace;font-size:.56rem;text-align:center;text-transform:uppercase}[data-course-shell=postgres] .arch-bottom span:last-child{border-right:0}[data-course-shell=postgres] .fault-section,[data-course-shell=postgres] .sources-section{background:var(--paper)}[data-course-shell=postgres] .fault-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));max-width:1540px;margin:0 auto;border-top:1px solid var(--line);border-left:1px solid var(--line)}[data-course-shell=postgres] .fault-grid article{min-height:190px;padding:22px;border-right:1px solid var(--line);border-bottom:1px solid var(--line);background:var(--white)}[data-course-shell=postgres] .fault-grid article:hover{background:#f8e6df}[data-course-shell=postgres] .fault-grid header{display:flex;justify-content:space-between;color:rgba(24,32,30,.42);font-family:var(--font-mono,ui-monospace),monospace;font-size:.62rem}[data-course-shell=postgres] .fault-grid header b{color:var(--orange)}[data-course-shell=postgres] .fault-grid h3{min-height:50px;margin:25px 0 22px;font-size:1rem;letter-spacing:-.035em}[data-course-shell=postgres] .fault-grid p{margin:0}[data-course-shell=postgres] .fault-grid p code,[data-course-shell=postgres] .fault-grid p span{display:block}[data-course-shell=postgres] .fault-grid p span{margin-bottom:4px;color:var(--ink-2);font-family:var(--font-mono,ui-monospace),monospace;font-size:.52rem;text-transform:uppercase}[data-course-shell=postgres] .fault-grid p code{overflow:hidden;color:var(--ink-2);font-family:var(--font-mono,ui-monospace),monospace;font-size:.6rem;text-overflow:ellipsis;white-space:nowrap}[data-course-shell=postgres] .verification-section{padding-bottom:80px;background:var(--white)}[data-course-shell=postgres] .verification-grid{max-width:1540px;margin:0 auto;border-top:2px solid var(--ink);border-bottom:2px solid var(--ink)}[data-course-shell=postgres] .verification-grid article{display:grid;grid-template-columns:70px minmax(0,1fr) auto;gap:24px;align-items:center;min-height:108px;padding:20px 6px;border-bottom:1px solid var(--line)}[data-course-shell=postgres] .verification-grid article:last-child{border-bottom:0}[data-course-shell=postgres] .verification-grid article>span{color:rgba(24,32,30,.4);font-family:var(--font-mono,ui-monospace),monospace;font-size:.68rem}[data-course-shell=postgres] .verification-grid h3,[data-course-shell=postgres] .verification-grid p{margin:0}[data-course-shell=postgres] .verification-grid h3{font-size:1rem}[data-course-shell=postgres] .verification-grid p{max-width:750px;margin-top:5px;color:var(--ink-2);font-size:.78rem}[data-course-shell=postgres] .verification-grid article>b{min-width:106px;padding:7px 9px;font-family:var(--font-mono,ui-monospace),monospace;font-size:.56rem;text-align:center}[data-course-shell=postgres] .verification-grid .verified{background:var(--mint)}[data-course-shell=postgres] .verification-grid .unverified{background:#f7b297}[data-course-shell=postgres] .source-list{max-width:1540px;margin:0 auto;padding:0 0 80px;border-top:2px solid var(--ink);list-style:none}[data-course-shell=postgres] .source-list li{display:grid;grid-template-columns:70px minmax(0,1fr) auto;gap:24px;align-items:center;min-height:76px;padding:10px 8px;border-bottom:1px solid var(--line)}[data-course-shell=postgres] .source-list li>span{color:rgba(24,32,30,.4);font-family:var(--font-mono,ui-monospace),monospace;font-size:.62rem}[data-course-shell=postgres] .source-list a{display:flex;flex-direction:column;gap:3px}[data-course-shell=postgres] .source-list a:hover b{color:var(--orange)}[data-course-shell=postgres] .source-list b{font-size:.82rem}[data-course-shell=postgres] .source-list small{color:var(--ink-2);font-size:.66rem}[data-course-shell=postgres] .source-list i{color:var(--orange);font-style:normal}[data-course-shell=postgres] footer{display:flex;align-items:center;justify-content:space-between;gap:30px;min-height:126px;padding:30px 4vw;background:var(--night);color:var(--white)}[data-course-shell=postgres] footer>div{display:flex;align-items:center;gap:12px}[data-course-shell=postgres] footer b{font-size:.82rem}[data-course-shell=postgres] footer a,[data-course-shell=postgres] footer p{color:rgba(255,255,255,.5);font-family:var(--font-mono,ui-monospace),monospace;font-size:.6rem}[data-course-shell=postgres] .copy-announcer{position:fixed;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)}@media (max-width:1180px){[data-course-shell=postgres] .hero{grid-template-columns:1fr .8fr;padding-right:4vw;padding-left:4vw}[data-course-shell=postgres] .course{grid-template-columns:290px minmax(0,1fr)}[data-course-shell=postgres] .course-nav{padding:28px 18px}[data-course-shell=postgres] .module{padding:44px 4vw}[data-course-shell=postgres] .fault-grid{grid-template-columns:repeat(3,minmax(0,1fr))}[data-course-shell=postgres] .lab-layout{grid-template-columns:1fr}[data-course-shell=postgres] .runbook{border-right:0;border-bottom:1px solid var(--line-dark)}}@media (max-width:900px){[data-course-shell=postgres] .version-chip{display:none}[data-course-shell=postgres] .hero{grid-template-columns:1fr;min-height:auto;gap:54px}[data-course-shell=postgres] .hero-copy{padding-top:20px}[data-course-shell=postgres] .hero-terminal{width:min(100%,620px);transform:none}[data-course-shell=postgres] .hero-stats{margin-top:0}[data-course-shell=postgres] .evidence-strip{grid-template-columns:repeat(2,minmax(0,1fr))}[data-course-shell=postgres] .evidence-card:nth-child(2){border-right:0}[data-course-shell=postgres] .course{display:block;border:0}[data-course-shell=postgres] .course-nav{position:relative;top:0;z-index:5;max-height:none;border-right:0;border-bottom:1px solid var(--line)}[data-course-shell=postgres] .course-nav nav{display:flex;gap:8px;overflow-x:auto;scroll-snap-type:x mandatory;padding-bottom:8px}[data-course-shell=postgres] .module-link{flex:0 0 235px;border:1px solid var(--line);scroll-snap-align:start}[data-course-shell=postgres] .module-link:last-child{border-bottom:1px solid var(--line)}[data-course-shell=postgres] .reset-button,[data-course-shell=postgres] .search-field{display:none}[data-course-shell=postgres] .section-lead{grid-template-columns:100px minmax(0,1fr)}[data-course-shell=postgres] .section-lead>p:last-child{grid-column:2}[data-course-shell=postgres] .fault-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}@media (max-width:640px){[data-course-shell=postgres] .topbar{min-height:60px;padding:0 16px}[data-course-shell=postgres] .wordmark{font-size:.76rem}[data-course-shell=postgres] .topbar-meta{gap:8px}[data-course-shell=postgres] .hero{padding:64px 20px 36px}[data-course-shell=postgres] .hero h1{font-size:clamp(3.2rem,17vw,5.4rem)}[data-course-shell=postgres] .hero-actions{display:grid;grid-template-columns:1fr}[data-course-shell=postgres] .button{width:100%}[data-course-shell=postgres] .hero-terminal{box-shadow:12px 12px 0 rgba(159,227,192,.07)}[data-course-shell=postgres] .hero-terminal pre{padding:20px 16px;font-size:.66rem}[data-course-shell=postgres] 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.complete-button{grid-column:1/-1;justify-content:center;width:100%}[data-course-shell=postgres] .module-meta>div{display:block;padding:18px 6px}[data-course-shell=postgres] .module-meta>div+div{padding-left:12px}[data-course-shell=postgres] .module-meta span{font-size:1.25rem}[data-course-shell=postgres] .module-meta p{margin-top:4px;font-size:.5rem}[data-course-shell=postgres] .concept-block{grid-template-columns:1fr;gap:14px}[data-course-shell=postgres] .learning-section summary{grid-template-columns:32px minmax(0,1fr) 20px;gap:8px;padding:14px 0}[data-course-shell=postgres] .learning-section summary .evidence-badge{grid-column:2;width:-moz-max-content;width:max-content}[data-course-shell=postgres] .learning-section summary i{grid-column:3;grid-row:1}[data-course-shell=postgres] .section-body{padding:0 0 26px 40px}[data-course-shell=postgres] .section-body pre{margin-left:-40px;padding:18px;font-size:.65rem}[data-course-shell=postgres] .quiz-item summary{grid-template-columns:38px minmax(0,1fr);gap:8px}[data-course-shell=postgres] .quiz-item summary>b{grid-column:2}[data-course-shell=postgres] .quiz-item p{grid-template-columns:1fr;padding:20px}[data-course-shell=postgres] .module-pager{grid-template-columns:1fr}[data-course-shell=postgres] .section-lead{display:block;padding:58px 20px 34px}[data-course-shell=postgres] .section-lead .section-index{margin-bottom:14px}[data-course-shell=postgres] .section-lead>p:last-child{margin-top:22px}[data-course-shell=postgres] .architecture,[data-course-shell=postgres] .runbook{padding:34px 20px 44px}[data-course-shell=postgres] .runbook li{grid-template-columns:30px minmax(0,1fr);gap:10px;padding:15px 0}[data-course-shell=postgres] .runbook li button{grid-column:2;width:64px}[data-course-shell=postgres] .runbook li code{display:block;overflow-x:auto;white-space:nowrap}[data-course-shell=postgres] .arch-flow{grid-template-columns:1fr;gap:8px;padding:28px 0}[data-course-shell=postgres] .arch-flow>div{min-height:104px}[data-course-shell=postgres] .arch-arrow{transform:rotate(90deg);justify-self:center}[data-course-shell=postgres] .fault-grid{grid-template-columns:1fr;margin:0 20px}[data-course-shell=postgres] .fault-grid article{min-height:164px}[data-course-shell=postgres] .verification-section{padding-bottom:60px}[data-course-shell=postgres] .source-list,[data-course-shell=postgres] .verification-grid{margin:0 20px}[data-course-shell=postgres] .verification-grid article{grid-template-columns:36px minmax(0,1fr);gap:12px}[data-course-shell=postgres] .verification-grid article>b{grid-column:2;justify-self:start}[data-course-shell=postgres] .source-list{padding-bottom:56px}[data-course-shell=postgres] .source-list li{grid-template-columns:34px minmax(0,1fr) auto;gap:8px}[data-course-shell=postgres] footer{align-items:flex-start;flex-direction:column;padding:32px 20px}}@media (prefers-reduced-motion:reduce){[data-course-shell=postgres]{scroll-behavior:auto}[data-course-shell=postgres] *,[data-course-shell=postgres] :after,[data-course-shell=postgres] :before{scroll-behavior:auto!important;transition-duration:.01ms!important;animation-duration:.01ms!important;animation-iteration-count:1!important}}@media print{[data-course-shell=postgres] .complete-button,[data-course-shell=postgres] .course-nav,[data-course-shell=postgres] .hero-actions,[data-course-shell=postgres] .module-pager,[data-course-shell=postgres] .runbook button,[data-course-shell=postgres] .topbar,[data-course-shell=postgres] footer{display:none!important}[data-course-shell=postgres] .hero,[data-course-shell=postgres] .lab-section{background:white;color:black}[data-course-shell=postgres] .course,[data-course-shell=postgres] .lab-layout,[data-course-shell=postgres] .learning-section:not([open])>:not(summary){display:block}}