:root{--lt-blue:#3f7fbd;--lt-deep:#2f6faa;--lt-pale:#eaf6ff;--lt-line:#b8d7e8;--lt-link:#0372a6;--lt-text:#000}*{box-sizing:border-box}html,body{margin:0;min-height:100%;background:#fff;color:var(--lt-text);font:16px/1.48 "Atkinson Hyperlegible",Tahoma,Arial,serif}a{color:var(--lt-link);text-decoration:none}a:hover{text-decoration:underline}.skip{position:absolute;left:-999px;top:auto}.skip:focus{left:38px;top:8px;background:#fff;padding:8px;z-index:20}.side-rail{position:fixed;left:0;top:0;bottom:0;width:24px;background:#3f7fbd;color:#fff;z-index:10;display:flex;flex-direction:column;justify-content:space-around;align-items:center;border-right:1px solid #2f6faa}.side-rail span{writing-mode:vertical-rl;transform:rotate(180deg);font-weight:700;font-size:13px;letter-spacing:.01em}.top-notice{height:58px;background:#eef8ff;border-bottom:1px solid var(--lt-line);display:flex;align-items:center;justify-content:center;gap:4px;text-align:center;font-weight:700;color:#111;padding:0 20px}.site-head{border-bottom:1px solid #94b7c9;background:#fff}.head-inner{max-width:1280px;margin:0 auto;padding:8px 0 10px}.brand{display:block;width:365px;max-width:72vw;height:auto}.reader-link{display:inline-flex;align-items:center;gap:6px;color:#345b75;font-size:13px;margin:4px 0 0 12px}.utility{background:#ddd;border-bottom:1px solid #9db4bf}.utility-inner{max-width:1280px;height:60px;margin:0 auto;display:flex;align-items:center;justify-content:flex-start;gap:10px}.launch{width:36px;height:36px;border:0;border-radius:4px;background:#fff;color:#387bb5;box-shadow:0 1px 2px rgba(0,0,0,.18);display:flex;align-items:center;justify-content:center;padding:0}.launch img{width:18px;height:32px;display:block}.search{display:flex;align-items:center;gap:6px;flex:0 0 auto}.search input{width:225px;height:36px;border:1px solid #bfc7cf;border-radius:4px;padding:0 12px;color:#555;background:#fff;font:19.2px/1.2 "Atkinson Hyperlegible",Tahoma,Arial,serif}.signin{display:flex;align-items:center;gap:6px;color:#333;font-size:16px;margin-left:auto;width:110px}.crumbbar{background:#eef8ff;border-bottom:1px solid #b8d7e8}.crumb-inner{max-width:1280px;margin:0 auto;min-height:44px;display:flex;align-items:center;gap:10px;color:#4c7898;font-size:14px}.crumb-inner .contents{font-weight:700}.crumb-inner a,.crumb-inner span{display:inline-flex;align-items:center;gap:6px}.crumb-inner .sep{color:#8aa8ba}.page{margin-left:0}.page-inner{max-width:1280px;margin:0 auto;padding:24px 0 0}.title-row{display:flex;align-items:flex-start;justify-content:space-between;border-bottom:1px solid #e5e7eb;margin-bottom:55px;gap:24px}.title-row>div{flex:1}h1{font-size:27.2px;line-height:25px;color:#0372a6;font-weight:400;margin:4px 0;padding:0 0 6.8px}.modified{font-size:13px;color:#666;margin:0 0 12px 10px}.modified b{color:#111}.donate{margin-top:34px;background:#4d7d1d;color:#fff;border:0;border-radius:3px;padding:8px 13px;font-weight:700;font-size:12px}main{min-height:560px}main :is(h2,h3,h4){color:#0372a6}main p{font-size:17.6px;line-height:1.5;margin:12.8px 0}main img{max-width:100%;height:auto}main table{border-collapse:separate;border-spacing:0;font-size:16px;line-height:1.2}main td,main th{border:1px solid #111;padding:16px;font-size:16px;line-height:1.2;vertical-align:middle}main table.mt-responsive-table{width:100%}main ul,main ol{margin:16px 0;padding-left:24px}main li{font-size:17.6px;line-height:1.4;margin:4.4px 0}main h2{font-size:24px!important;line-height:1.2!important;margin:24px 0 0!important}main h3{font-size:20.8px!important;line-height:1.2!important;margin:20.8px 0 0!important}main :is(.box-objectives,.box-example,.box-exercise,.box-note){background:#f1f9fe!important;border-left:4px solid #127abf!important;margin:12.8px 0!important;padding:0 10px 1px!important;display:block!important;clear:both!important}main :is(.box-objectives,.box-example,.box-exercise,.box-note)>.mt-section{margin:0!important;padding:0!important}main :is(.box-objectives,.box-example,.box-exercise,.box-note) .box-legend{color:#0372a6!important;font-size:24px!important;line-height:1.2!important;font-weight:700!important;margin:24px 0 0!important;padding:0!important}main :is(.box-objectives,.box-example,.box-exercise,.box-note) .box-legend .lt-icon-default{color:inherit!important;font:inherit!important}main .mt-align-center{text-align:center!important}main .mt-align-left{text-align:left!important}main .mt-align-right{text-align:right!important}main figure{display:flex;flex-direction:column;align-items:center;text-align:center;margin:0 auto 4.8px}main figure img{display:inline-block}main figcaption{font-size:16px;line-height:20px;color:#444;margin:4.8px 0;text-align:center}main .source-content-main{display:block}main .source-accessibility-footer{margin:12px 0 0;padding:0}main .source-accessibility-footer p{font-size:13px;line-height:1.5;margin:12.8px 0}main .source-accessibility-footer small{font-size:100%}main mjx-container[jax="SVG"][display="true"]{display:block;text-align:center;margin:1em 0;font-size:85%;line-height:1.2}main mjx-container[jax="SVG"]>svg{overflow:visible}main .mt-dekiscript-error{display:none!important}main .mt-video-widget{margin-left:auto!important;margin-right:auto!important}main .mt-video-width-55{width:55%!important}main iframe[style*="position: absolute"]{left:0!important;top:0!important}main .youtubeImageContainer{display:none!important}main img.right,main .internal.right{float:right;margin:0 0 18px 26px}main img.left,main .internal.left{float:left;margin:0 26px 18px 0}main .mt-section:after{content:"";display:block;clear:both}main .mt-topic-hierarchy-listings.mt-guide-listings{list-style:none!important;margin:42px 0 0!important;padding:0 24px!important;display:grid!important;grid-template-columns:repeat(2,598px)!important;column-gap:18px!important;row-gap:36px!important;align-items:start!important;justify-content:start!important}main .mt-topic-hierarchy-listings.mt-guide-listings>li{margin:0!important;padding:0!important}main .mt-topic-hierarchy-listings.mt-guide-listings .mt-listing-detailed{margin:0!important;padding:0 0 0 32px!important;position:relative!important}main .mt-topic-hierarchy-listings.mt-guide-listings .mt-listing-detailed-title{margin:0 0 8px!important;padding:0!important;font-size:21px!important;line-height:1.25!important;font-weight:500!important;color:#2f7293!important}main .mt-topic-hierarchy-listings.mt-guide-listings .mt-listing-detailed-title:before{content:"";position:absolute;left:0;top:2px;width:18px;height:23px;border:2px solid #777;border-radius:1px;background:repeating-linear-gradient(to bottom,transparent 0,transparent 4px,#777 4px,#777 5px,transparent 5px,transparent 8px)}main .mt-topic-hierarchy-listings.mt-guide-listings .mt-listing-detailed-title a{color:#2f7293!important;font-weight:500!important;text-decoration:none!important}main .mt-topic-hierarchy-listings.mt-guide-listings .mt-listing-detailed-overview{margin:0!important;padding:0!important;color:#111!important;font-size:17px!important;line-height:1.42!important}main .ch-grid{display:grid!important;grid-template-columns:repeat(3,1fr)!important;gap:16px!important;margin:18px 0 20px!important}main .ch-card{border:2px dashed #ccc!important;border-radius:0!important;padding:20px!important;text-align:center!important;min-height:156px!important;background:#fff!important}main .ch-card .ico{width:160px!important;height:96px!important;margin:0 auto 12px!important;background:#eaf6ff!important;border-radius:3px!important;display:flex!important;align-items:center!important;justify-content:center!important;font-size:30px!important;color:#0089c4!important}main .ch-card a{font-size:14px!important;color:#276d9a!important;font-weight:500!important}.site-foot{background:#eef8ff;border-top:1px solid #6fc2d4;margin-top:40px;min-height:164px}.foot-inner{max-width:1280px;margin:0 auto;padding:20px 0;color:#111;font-size:14px}.sponsors{display:flex;justify-content:center;gap:48px;margin-top:22px;align-items:center;min-height:34px}.sponsors img{max-height:38px;max-width:112px;object-fit:contain}.corner-tools{position:fixed;right:8px;top:0;width:24px;display:flex;flex-direction:column;gap:8px;z-index:10}.corner-tools span{width:23px;height:23px;background:#fff;border:1px solid #cfd8df;border-radius:3px;display:flex;align-items:center;justify-content:center;color:#777;font-size:14px}@media (max-width:900px){.side-rail,.corner-tools{display:none}.head-inner,.utility-inner,.crumb-inner,.page-inner,.foot-inner{padding-left:18px;padding-right:18px}.utility-inner{justify-content:flex-start}.signin{margin-left:auto}.title-row{margin-bottom:28px}main .mt-topic-hierarchy-listings.mt-guide-listings{grid-template-columns:1fr!important;padding:0!important}main .ch-grid{grid-template-columns:repeat(2,1fr)!important}}@media (max-width:560px){.top-notice{height:auto;min-height:46px;font-size:13px}.brand{width:310px}.search{display:none}.crumb-inner{flex-wrap:wrap;padding-top:8px;padding-bottom:8px}.title-row{display:block}.donate{margin:0 0 16px 0}main .ch-grid{grid-template-columns:1fr!important}}#mt-toc-container{display: none !important}.sponsors{flex-wrap:wrap!important;gap:18px 32px!important}.sponsors span{white-space:normal!important;overflow-wrap:anywhere;text-align:center}.brand,img,video,canvas,iframe{max-width:100%;height:auto}pre{max-width:100%;overflow:auto}.mirror-table-scroll{max-width:100%;overflow-x:auto}.mirror-blocked-resource,a{overflow-wrap:anywhere}main p,main li,main td,main th{overflow-wrap:anywhere;word-break:break-word}@media (max-width:560px){.sponsors{gap:14px 18px!important}}.mirror-inline-0606231e44bd83b1{font-size: 85%;min-width: 46.614ex;position: relative}.mirror-inline-0ae96fe78cf98cbe{font-size: 85%;min-width: 59.569ex;position: relative}.mirror-inline-0b147cba4a07c7ea{font-size: 85%;min-width: 75.685ex;position: relative}.mirror-inline-1beff43b2370a814{font-size: 85%;min-width: 50.698ex;position: relative}.mirror-inline-1ccca7d4f8f7f2cd{font-size: 85%;min-width: 79.279ex;position: relative}.mirror-inline-260683861d9d689d{font-size: 85%;min-width: 64.302ex;position: relative}.mirror-inline-2af20e4ee9a7e74a{height: 100px;width: 100px}.mirror-inline-2dfed7afb1749d83{font-size: 85%;min-width: 44.523ex;position: relative}.mirror-inline-322fa22edbd23c8f{font-size: 85%;min-width: 50.153ex;position: relative}.mirror-inline-34d5f8afd84ad536{font-size:12.0pt;line-height:107%}.mirror-inline-35a90107b5fecc3c{font-size: 85%;min-width: 50.8ex;position: relative}.mirror-inline-374f0656ab6ee613{font-size: 85%;min-width: 66.406ex;position: relative}.mirror-inline-3cc4552b18cec2ec{font-size: 85%;min-width: 51.32ex;position: relative}.mirror-inline-40124c5e03763f3e{font-size: 85%;min-width: 45.38ex;position: relative}.mirror-inline-4a05249595eade25{font-size: 85%;min-width: 68.139ex;position: relative}.mirror-inline-4df90376f554009e{font-size: 85%;min-width: 40.322ex;position: relative}.mirror-inline-4f6efef5a54e4adf{width: 100%;height: 0px;position: relative;padding-bottom: 56.25%}.mirror-inline-5664fcb8b5a1851b{font-size: 85%;min-width: 67.297ex;position: relative}.mirror-inline-5687e6f509c938a1{font-size: 85%;min-width: 70.411ex;position: relative}.mirror-inline-5cbdc1665194ba1c{font-size: 85%;min-width: 79.094ex;position: relative}.mirror-inline-5da82106adb9a1c8{font-size: 85%;min-width: 75.811ex;position: relative}.mirror-inline-620240bf31bb080d{font-size: 85%;min-width: 57.128ex;position: relative}.mirror-inline-6a47db2154aee05a{background-color: unset}.mirror-inline-6db558d491e275ab{width: 208px;height: 208px}.mirror-inline-71cf9f482b900113{font-size: 85%;min-width: 53.547ex;position: relative}.mirror-inline-77ca0dca009f8955{font-size: 85%;min-width: 57.728ex;position: relative}.mirror-inline-7bc136a1bdf4fe1a{list-style-type: lower-alpha}.mirror-inline-7cb66986e4bf8f45{font-size: 85%;min-width: 47.716ex;position: relative}.mirror-inline-7d437ec15d1da014{font-size: 85%;min-width: 48.555ex;position: relative}.mirror-inline-7e8243dbd381d8af{font-size: 85%;min-width: 44.042ex;position: relative}.mirror-inline-82e3b42191593dca{font-size: 85%;min-width: 80.619ex;position: relative}.mirror-inline-8716c3d6cd35bd66{font-size: 85%;min-width: 67.565ex;position: relative}.mirror-inline-8eeba9cd50b77bc7{font-size: 85%;min-width: 49.799ex;position: relative}.mirror-inline-98902d2885572349{font-size: 85%;min-width: 12.049ex;position: relative}.mirror-inline-9b7b71b064313c6c{font-size: 85%;min-width: 52.196ex;position: relative}.mirror-inline-9c4af0f0f0ec2c57{font-size:11.0pt;line-height:107%;font-family:Calibri,sans-serif;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language:AR-SA}.mirror-inline-9d12f20ccbe86f08{font-size: 85%;min-width: 89.909ex;position: relative}.mirror-inline-9e715d2e997aa951{font-size: 85%;min-width: 72.945ex;position: relative}.mirror-inline-a16a46ef36fc0281{font-size: 85%;min-width: 48.537ex;position: relative}.mirror-inline-a7c8985f273401af{font-size: 85%;min-width: 47.833ex;position: relative}.mirror-inline-ab7b11e2aa0d682c{font-size: 85%;min-width: 58.721ex;position: relative}.mirror-inline-aecafb99920c368d{font-size: 85%;min-width: 54.189ex;position: relative}.mirror-inline-b32a6ee9b957563a{font-size: 85%;min-width: 36.79ex;position: relative}.mirror-inline-b3481a6b8f0c204c{font-size: 85%;min-width: 48.995ex;position: relative}.mirror-inline-c9e15086dedf96e3{font-size: 85%;min-width: 65.239ex;position: relative}.mirror-inline-ca35f6e8132008ab{font-size: 85%;min-width: 54.773ex;position: relative}.mirror-inline-cebd5a3b69850058{font-size: 85%;min-width: 51.505ex;position: relative}.mirror-inline-d3847064dd58e1b3{font-size: 85%;min-width: 54.614ex;position: relative}.mirror-inline-d3d737bda47356a7{font-size: 85%;min-width: 74.617ex;position: relative}.mirror-inline-d3de73887db6309d{font-size: 85%;min-width: 45.001ex;position: relative}.mirror-inline-d650120ebd076be0{font-size: 85%;position: relative}.mirror-inline-d687376dbec66e92{font-size: 85%;min-width: 65.37ex;position: relative}.mirror-inline-dad4ac0bd94b04f0{font-size: 85%;min-width: 51.195ex;position: relative}.mirror-inline-db0b45c02a3fe599{font-size: 85%;min-width: 45.173ex;position: relative}.mirror-inline-de825350d7660159{font-size: 85%;min-width: 54.786ex;position: relative}.mirror-inline-e068d51b21e37261{font-size: 85%;min-width: 53.685ex;position: relative}.mirror-inline-e121a8f9d59ad902{list-style-type: upper-alpha}.mirror-inline-e15a0e642c5713a3{font-size: 85%;min-width: 48.654ex;position: relative}.mirror-inline-e50e4fcb39cb6fa6{font-size: 85%;min-width: 58.285ex;position: relative}.mirror-inline-e9d626b85c1e2e3c{font-size: 85%;min-width: 53.06ex;position: relative}.mirror-inline-ea1ca2753eabf04b{font-size: 85%;min-width: 80.472ex;position: relative}.mirror-inline-f4d463c46981353e{font-size: 85%;min-width: 71.222ex;position: relative}.mirror-inline-fcdfd24690d29bd1{font-size: 85%;min-width: 52.479ex;position: relative}