:root{--header-space:112px}
html{scroll-padding-top:125px}
.header-shell{height:var(--header-space);position:relative;z-index:60}
.header-shell .site-header{position:absolute;top:0;left:0;right:0;width:100%;height:var(--header-space);z-index:60;background:#fff;box-sizing:border-box;transition:top .24s,left .24s,right .24s,height .24s,padding .24s,background .24s,border-radius .24s,box-shadow .24s}
.header-shell .site-header.is-floating{position:fixed;top:14px;left:max(24px,calc((100vw - 1560px)/2));right:max(24px,calc((100vw - 1560px)/2));width:auto;height:84px;padding:0 34px;border:1px solid #ffffffb3;border-radius:24px;background:#ffffffc2;-webkit-backdrop-filter:blur(20px) saturate(140%);backdrop-filter:blur(20px) saturate(140%);box-shadow:0 5px 28px #00000010,0 1px 3px #00000004}
.site-header.is-floating .header-note{line-height:1.7}
.site-header.is-floating .brand-name{font-size:34px}
.site-header.is-floating .brand-sub{font-size:5px;letter-spacing:1.9px}
.back-to-top{position:fixed;right:26px;bottom:calc(24px + env(safe-area-inset-bottom,0px));width:44px;height:44px;min-width:44px;min-height:44px;padding:0;border:1px solid #17171735;border-radius:50%;display:grid;place-items:center;z-index:55;background:#ffffffd9;color:#171717;-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);box-shadow:0 3px 16px #00000008;transition:background .2s,border-color .2s,box-shadow .2s}
.back-to-top[hidden]{display:none}
.back-to-top-icon{display:block;width:19px;height:19px;fill:none;stroke:currentColor;stroke-width:1.3;stroke-linecap:round;stroke-linejoin:round}
.back-to-top:hover{background:#fff;border-color:#17171780;box-shadow:0 4px 20px #00000012}
.back-to-top:focus-visible{outline:2px solid #171717;outline-offset:4px}
body.modal-open .back-to-top{visibility:hidden}
@media(max-width:1100px){.header-shell .site-header.is-floating{left:18px;right:18px;padding:0 28px}}
@media(max-width:760px){:root{--header-space:89px}html{scroll-padding-top:110px}.header-shell .site-header.is-floating{top:10px;left:12px;right:12px;height:70px;padding:0 20px;border-radius:21px;background:#ffffffcc}.site-header.is-floating .brand-name{font-size:29px}.site-header.is-floating .brand-sub{font-size:5px;letter-spacing:1.65px}.site-header.is-floating .brand-branch{top:3px;right:-27px;width:28px;height:25px}.site-header.is-floating .main-nav{top:calc(100% + 9px);left:0;right:0;max-height:calc(100svh - 115px);overflow-y:auto;padding:22px 23px 28px;background:#fffffff2;border:1px solid #fff;border-radius:21px;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);box-shadow:0 8px 25px #00000012}.back-to-top{right:17px;bottom:calc(18px + env(safe-area-inset-bottom,0px));width:42px;height:42px;min-width:42px;min-height:42px}.back-to-top-icon{width:18px;height:18px}}
@media(prefers-reduced-motion:reduce){.header-shell .site-header,.back-to-top{transition:none}}