:root{--font: "IBM Plex Sans","Helvetica Neue",sans-serif;--tool-display: "Jersey 10","IBM Plex Sans",sans-serif;--control-line: #83917d;--seal: #397529;--selected: #e2ecd3;--danger-ink: #873c1c;--grass: #79a946}html:is(:lang(zh),:lang(ja),:lang(ko),:lang(ru)){--tool-display: var(--font)}html:lang(zh){--font: "IBM Plex Sans","PingFang SC","PingFang TC","Microsoft YaHei",sans-serif}html:lang(zh-Hant){--font: "IBM Plex Sans","PingFang TC","Microsoft JhengHei",sans-serif}html:lang(ja){--font: "IBM Plex Sans","Hiragino Kaku Gothic ProN","Yu Gothic",sans-serif}html:lang(ko){--font: "IBM Plex Sans","Apple SD Gothic Neo","Malgun Gothic",sans-serif} .language-control{position: relative;grid-column: 2;grid-row: 1;justify-self: end;min-width: 0}.language-picker{position: relative}.language-picker summary{display: flex;align-items: center;gap: 8px;min-height: 44px;min-width: 154px;max-width: 190px;padding: 9px 10px;list-style: none;border: 1px solid var(--control-line);border-radius: 4px;background: var(--paper);color: var(--ink);font: 600 14px/1.35 var(--font);cursor: pointer;user-select: none;touch-action: manipulation;transition: transform 120ms cubic-bezier(.23,1,.32,1)}.language-picker summary::-webkit-details-marker{display: none}.language-picker summary:active{transform: scale(.98)}.language-picker[open] summary{border-color: var(--seal);background: var(--selected)}.language-picker .selected-name{min-width: 0;overflow: hidden;text-overflow: ellipsis;white-space: nowrap}.pixel-globe{width: 20px;height: 20px;flex: none;color: var(--seal);shape-rendering: crispEdges}.language-chevron{width: 10px;height: 10px;margin-left: auto;flex: none;transition: transform 180ms cubic-bezier(.23,1,.32,1)}.language-picker[open] .language-chevron{transform: rotate(180deg)}.language-panel{position: absolute;z-index: 2;right: 0;top: calc(100% + 12px);width: min(362px,calc(100vw - 40px));max-height: min(620px,calc(100dvh - 96px));padding: 16px;overflow: auto;overscroll-behavior: contain;border: 1px solid var(--control-line);border-top: 3px solid var(--seal);border-radius: 5px;color: var(--ink);background: var(--paper);box-shadow: 0 12px 28px rgb(35 56 32 / 15%),0 2px 3px rgb(35 56 32 / 7%);transform-origin: top right;opacity: 1;transform: translateY(0) scale(1);transition: transform 180ms cubic-bezier(.23,1,.32,1),opacity 180ms cubic-bezier(.23,1,.32,1)}.language-panel-heading{display: flex;align-items: center;gap: 11px;margin-bottom: 14px;padding-inline: 1px;font: 600 16px/1.35 var(--font)}.pixel-book{width: 35px;height: 31px;flex: none;overflow: visible;shape-rendering: crispEdges}.book-left,.book-right{transform-origin: 17px 15px;transform: rotateY(0deg);transition: transform 180ms cubic-bezier(.23,1,.32,1)}@starting-style{.language-picker[open] .language-panel{opacity: 0;transform: translateY(-5px) scale(.97)}.language-picker[open] .book-left{transform: rotateY(55deg)}.language-picker[open] .book-right{transform: rotateY(-55deg)}}.language-switch{display: grid;grid-template-columns: repeat(2,minmax(0,1fr));gap: 5px;font: 14px/1.4 var(--font)}.language-switch > a{display: flex;align-items: center;justify-content: space-between;gap: 5px;min-width: 0;min-height: 48px;padding: 8px 9px;border: 1px solid transparent;border-radius: 4px;color: var(--ink);background: var(--paper);text-decoration: none;touch-action: manipulation}.language-name{min-width: 0;overflow-wrap: anywhere}.language-check{flex: none;color: var(--seal);visibility: hidden}.language-switch > a[aria-current="true"]{border-color: #c9d9b8;background: var(--selected);font-weight: 600}.language-switch > a[aria-current="true"] .language-check{visibility: visible}.language-picker summary:focus-visible,.language-switch a:focus-visible{outline: 3px solid #508fba;outline-offset: 3px}.language-status{grid-column: 1 / -1;margin: 4px 0 0;padding: 10px;border-top: 1px solid var(--line);background: var(--paper);color: var(--danger-ink);overflow-wrap: anywhere}.language-status a{display: inline-flex;min-height: 44px;align-items: center;font-weight: 600}.language-picker[data-keyboard] :is(.language-panel,.book-left,.book-right,.language-chevron),.language-control[data-keyboard] :is(.language-panel,.book-left,.book-right,.language-chevron){transition: none} .language-discovery-cue{position: absolute;right: 0;top: calc(100% + 1px);width: 144px;height: 30px;pointer-events: none;z-index: 1}.language-discovery-cue[hidden]{display: none !important}.cue-art{display: block;width: 144px;height: 30px;overflow: visible;shape-rendering: crispEdges}.cue-cube,.cube-fragment,.cue-hand{transform-box: fill-box;transform-origin: center}.cube-whole,.cue-hand,.cube-fragment,.crack-one,.crack-two,.cue-label{opacity: 0}.cue-label{position: absolute;left: 80px;top: 7px;max-width: 64px;color: var(--accent);font: 600 10px/14px var(--font);white-space: nowrap;text-shadow: 0 1px var(--paper)}@media (hover: hover) and (pointer: fine){.language-picker summary:hover{background: var(--selected)}.language-switch > a:hover{border-color: var(--control-line);background: #eef2e4}}@media (prefers-reduced-motion: reduce){.language-discovery-cue{display: none !important}.language-picker :is(.language-panel,.book-left,.book-right,.language-chevron){transition: none}}.site-header{--accent: #316b2a;position: relative;isolation: isolate;z-index: 30;display: grid;grid-template-columns: minmax(0,1fr) auto;align-items: center;gap: 16px;min-height: 88px;padding: 12px 8px}.site-header::before{content: "";position: absolute;z-index: -1;inset: 0;background: var(--paper);border-bottom: 1px solid var(--line)}.brand{display: flex;min-width: 0;justify-self: start;flex-direction: column;align-items: flex-start;gap: 4px;text-decoration: none;color: var(--ink)}.site-header .brand .brand-logo{display: block;width: 210px;max-width: 100%;height: auto}.brand .tagline{display: none}.nav{width: 100%;padding-top: 10px;border-top: 1px solid var(--line);grid-column: 1 / -1;grid-row: 2;display: grid;grid-template-columns: repeat(6,minmax(0,1fr));gap: 8px;font-family: var(--tool-display);font-size: 24px;font-weight: 400;font-synthesis: none;line-height: 1.1}.nav a{display: flex;align-items: center;justify-content: center;min-height: 48px;gap: 8px;padding: 10px 12px;border: 1px solid transparent;border-radius: 4px;background: transparent;color: var(--ink);text-decoration: none;text-align: center;min-width: 0;white-space: normal;text-wrap: balance;transition: background-color 140ms ease,border-color 140ms ease}.nav img{width: 24px;height: 24px;flex-shrink: 0}.nav a:hover{color: var(--accent);background: var(--selected)}.nav a[aria-current="page"]{color: var(--accent);background: var(--selected);border-color: transparent;box-shadow: inset 0 -3px var(--grass)}@media (max-width: 980px){.site-header{grid-template-columns: minmax(0,1fr) auto;gap: 12px;padding: 14px 0 12px}.brand{grid-column: 1;grid-row: 1;justify-self: start}.site-header .brand .brand-logo{width: 210px}.language-control{grid-column: 2;grid-row: 1}.language-discovery-cue{top: calc(100% - 2px)}.nav{grid-column: 1 / -1;grid-row: 2;grid-template-columns: repeat(3,minmax(0,1fr));justify-self: center;width: 100%;padding-top: 12px;border-top: 1px solid var(--line);font-size: 24px;gap: 6px}.nav a{min-width: 0;min-height: 48px;padding: 8px 6px;gap: 8px;white-space: normal;text-wrap: balance}.nav img{width: 20px;height: 20px}}@media (max-width: 540px){.site-header{gap: 12px 8px}.site-header .brand .brand-logo{width: 170px}.language-picker summary{min-width: 0;max-width: 168px;gap: 6px;padding-inline: 9px;font-size: 13px}.language-picker .selected-name{max-width: 108px}.pixel-globe{width: 18px;height: 18px} .language-panel{width: min(344px,calc(100vw - 40px));padding: 13px;top: calc(100% + 10px);max-height: calc(100dvh - 90px)}.language-switch{font-size: 13px}.language-switch > a{padding: 8px}.nav{grid-template-columns: repeat(2,minmax(0,1fr));gap: 2px;font-size: 22px}.nav a{min-height: 44px;padding-inline: 4px;gap: 6px}.nav img{width: 16px;height: 16px}}@media (max-width: 360px){.site-header .brand .brand-logo{width: 132px}.language-picker summary{max-width: 142px;padding-inline: 7px;font-size: 12px}.language-picker .selected-name{max-width: 86px}.pixel-globe{width: 17px;height: 17px}.language-panel{padding: 11px}.language-panel-heading{font-size: 15px}.language-switch{font-size: 12px}.language-switch > a{padding: 7px 6px;gap: 3px}.language-discovery-cue{width: 136px}.cue-art{width: 136px}.cue-label{left: 76px;font-size: 9px}}.site-header .brand{grid-column: 1;grid-row: 1}.site-header .nav a:focus-visible{outline: 3px solid #508fba;outline-offset: 2px}html:is(:lang(zh),:lang(ja),:lang(ko),:lang(ru)) .nav{font-size: 18px;font-weight: 600}html:is(:lang(de),:lang(ru)) .nav a{overflow-wrap: anywhere;hyphens: auto}@media (max-width: 540px){html:is(:lang(zh),:lang(ja),:lang(ko),:lang(ru)) .nav{font-size: 15px}} @media (max-width: 600px){.language-discovery-cue{display: none !important}} @media (max-width: 540px){.nav{display: flex;gap: 4px;overflow-x: auto;padding-top: 8px;scroll-snap-type: x proximity;scrollbar-width: none;-webkit-mask-image: linear-gradient(90deg,#000 88%,transparent);mask-image: linear-gradient(90deg,#000 88%,transparent)}.nav::-webkit-scrollbar{display: none}.nav a{flex: 0 0 auto;padding-inline: 12px;white-space: nowrap;scroll-snap-align: start}}