:root{--ink:#2a444e;--sub:#6a7e86;--blue:#557b8c;--sky:#eef4f6;--line:#d5dfe3;--cream:#f6f2e7;--accent:#b8a36e}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:24px}
body{margin:0;background:#fff;color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"Hiragino Kaku Gothic ProN","Yu Gothic",sans-serif;line-height:2;letter-spacing:.025em;line-break:strict;overflow-wrap:anywhere}
a{color:inherit;text-underline-offset:.25em}a:hover{opacity:.75}a,summary{touch-action:manipulation}a:focus-visible,summary:focus-visible,button:focus-visible{outline:3px solid var(--accent);outline-offset:4px}
img{display:block;width:100%;height:auto}h1,h2,h3,p,figure{margin:0}h1,h2,h3{line-height:1.75;word-break:normal;font-weight:500}h1,h2{font-family:"Yu Mincho","Hiragino Mincho ProN",serif}button,summary{font:inherit}
.wrap{width:min(1080px,calc(100% - 80px));margin-inline:auto}.reading{width:min(700px,calc(100% - 48px));margin-inline:auto}
.preview{background:#f5f4ef;color:var(--sub);font-size:10px;text-align:center;padding:3px 15px}.skip{position:absolute;top:-100px;left:10px;background:white;padding:10px;z-index:30}.skip:focus{top:10px}
.site-header{background:#fff}.header{display:grid;grid-template-columns:1fr 195px 210px 168px;grid-template-rows:84px 62px;column-gap:22px;align-items:center}.brand{grid-column:1;grid-row:1}.logo{display:inline-block;font:40px/1 Georgia,serif;letter-spacing:.16em;text-decoration:none}.brand small{display:block;font-size:10px;color:var(--sub);line-height:1.4;margin-top:10px;letter-spacing:.05em}
.header-area{grid-column:2;grid-row:1;border:1px solid var(--line);border-radius:24px;text-align:center;padding:8px 10px;font-size:10px;color:var(--sub);text-decoration:none;white-space:nowrap}
.header-phone{grid-column:3;grid-row:1;text-align:center}.header-phone a{font-size:23px;font-weight:500;letter-spacing:.02em;text-decoration:none;white-space:nowrap;line-height:1.3;display:block;color:var(--blue)}.header-phone small{font-size:10px;color:var(--sub);display:block;margin-top:5px}
.header-cta{grid-column:4;grid-row:1/3;align-self:stretch;background:linear-gradient(145deg,#9bb9c6,#789ba9);color:white;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:8px;border-radius:0 0 5px 5px;text-decoration:none;text-align:center;font-size:14px;line-height:1.8}.header-cta svg{width:31px;height:25px}.desktop-nav{grid-column:1/4;grid-row:2;display:flex;align-items:center;justify-content:space-between;gap:8px}.desktop-nav a{border-left:3px dotted #a6b9c0;padding-left:16px;text-decoration:none;font-size:12px;color:var(--blue);font-weight:500;white-space:nowrap}.desktop-nav a:last-child{background:var(--blue);color:#fff;border:0;padding:7px 15px;border-radius:3px}.mobile-nav{display:none}
.breadcrumbs{display:flex;align-items:center;gap:14px;padding-block:22px;font-size:10px;color:var(--sub);line-height:1.9;flex-wrap:wrap}.breadcrumbs a{text-decoration:none}.breadcrumbs .separator{color:var(--blue);font-size:15px}.breadcrumbs span:last-child{color:var(--ink)}
.column-banner{height:184px;display:grid;place-items:center;position:relative;isolation:isolate;background:linear-gradient(100deg,#47677c55,#6d8e9c66),url('assets/sky.jpg') center 43%/cover}.column-banner:after{content:'';position:absolute;inset:0;background:#35546b15;z-index:-1}.column-banner p{color:#fff;font-family:"Yu Mincho","Hiragino Mincho ProN",serif;font-size:29px;letter-spacing:.17em;text-shadow:0 1px 8px #3a596770}
.article-top{width:min(900px,calc(100% - 80px));margin:60px auto 0;display:grid;grid-template-columns:1fr 1fr;column-gap:40px;align-items:start}.article-head{grid-column:2;grid-row:1;padding-top:0}.article-date{font-size:12px;color:var(--sub);line-height:1.6;margin-bottom:8px}.article-head h1{font-size:24px;color:var(--blue);line-height:1.8;letter-spacing:.015em;padding-bottom:24px;border-bottom:1px dashed #c8d3d7}.title-phrase{display:inline-block}.article-tag{display:inline-flex;align-items:center;gap:9px;font-size:11px;line-height:1.6;background:#e8dfc7;color:#5a513e;border-radius:20px;padding:4px 16px;margin-top:18px;text-decoration:none}.article-picture{grid-column:1;grid-row:1}.article-picture img{aspect-ratio:1.5;object-fit:cover}.article-picture figcaption{font-size:10px;color:var(--sub);line-height:1.7;margin-top:8px}.byline{font-size:10px;color:var(--sub);line-height:1.7;margin-top:16px}
.intro{padding-top:42px;padding-bottom:50px}.intro p{font-size:14px;line-height:2.05}.intro p+p{margin-top:27px}.intro .answer{font-weight:400;font-size:14px}.intro .intro-question{font-size:15px;font-weight:500;color:var(--blue);margin-bottom:25px}
.toc{border:1px solid #b7c8cf;background:#fbfcfc;width:min(470px,100%);padding:22px 24px;margin:36px 0 0}.toc-heading{display:flex;align-items:center;gap:18px;justify-content:center;margin-bottom:14px}.toc h2{font-family:inherit;font-size:15px;color:var(--ink)}.toc-toggle{border:0;background:none;color:var(--blue);padding:2px 0;cursor:pointer;font-size:11px;text-decoration:underline;text-underline-offset:3px}.toc ol{margin:0;padding-left:1.45em;font-size:13px;line-height:1.9}.toc li+li{margin-top:9px}.toc ol ol{margin-top:5px;padding-left:1.3em;font-size:12px;color:var(--sub)}.toc ol ol li+li{margin-top:4px}.toc a{text-decoration:none;color:var(--blue)}.toc[aria-expanded="false"]>ol{display:none}
.chapter{padding-block:0 50px;border:0}.chapter h2{position:relative;min-height:65px;padding:13px 94px 17px 0;border-bottom:2px dashed #d3dde1;margin-bottom:27px;font-size:23px;line-height:1.7;letter-spacing:.015em}.chapter h2:after{content:'';position:absolute;right:0;bottom:6px;width:79px;height:58px;background:url('assets/house.svg') right bottom/contain no-repeat}.section-num{display:none}.chapter h3{position:relative;font-family:inherit;font-size:18px;font-weight:500;line-height:1.8;margin:30px 0 20px;padding-left:25px}.chapter h3:before{content:'';position:absolute;left:0;top:4px;width:7px;height:calc(100% - 8px);min-height:22px;max-height:36px;background:#789ba9;border-radius:5px}.chapter p,.chapter li{font-size:14px;line-height:2.05}.chapter p+p{margin-top:26px}.chapter ul{padding-left:1.4em}.chapter li+li{margin-top:9px}.chapter a{color:#5c91a7}.source{font-size:12px!important;color:var(--sub);margin-top:22px!important;line-height:1.9!important}.source a{color:#5c91a7}.phrase{display:inline}
.table-wrap{margin-top:23px;overflow-x:auto;border:1px solid var(--line)}table{width:100%;border-collapse:collapse;font-size:12px;line-height:1.8;text-align:left}caption{padding:12px!important;text-align:left;background:#fafcfc;font-size:11px!important;color:var(--sub)}th,td{border:1px solid var(--line);padding:14px 13px;vertical-align:top}thead{background:#ebf1f3}th{font-weight:500}tbody th{background:#f7f9fa}.model{white-space:nowrap}.spec-table td:nth-child(2),.spec-table td:nth-child(3){white-space:nowrap}.table-tip{font-size:11px!important;color:var(--sub);margin-bottom:8px}.warranty-table th{width:28%}.warranty-table td{font-size:13px}.note{background:#f6f4ec;padding:20px 23px;margin-top:25px;font-size:13px!important;border:1px solid #e6e0d0;border-radius:2px}.decision{display:block}.decision>div{margin-top:25px}.decision ul{margin-top:0}.decision h3{margin-top:0}.inline-link{display:inline-block;margin-top:22px;font-size:13px}
.checklist{list-style:none;padding:0!important;margin-block:26px}.checklist li{position:relative;padding:17px 16px 17px 40px;background:#f4f8f9;border-bottom:1px solid #e1eaed}.checklist li+li{margin-top:0}.checklist li:before{content:'✓';position:absolute;left:16px;top:18px;color:var(--blue)}.checklist strong{display:block;font-weight:500}.checklist span{display:block;font-size:13px;color:var(--sub);margin-top:3px}
.battery-photo{display:grid;grid-template-columns:200px 1fr;gap:27px;align-items:center;margin-block:28px}.battery-photo img{aspect-ratio:.85;object-fit:cover;object-position:center 49%;border-radius:2px}.battery-photo figcaption{font-size:13px;line-height:2;color:var(--sub)}.battery-photo strong{display:block;font-family:Georgia,serif;font-weight:400;font-size:26px;letter-spacing:.04em;color:var(--blue);margin-bottom:8px}
.faq details{border:0;padding:0 0 25px}.faq summary{position:relative;list-style:none;cursor:pointer;font-size:17px;font-weight:500;line-height:1.8;padding-left:25px;padding-right:25px;margin-bottom:14px}.faq summary::-webkit-details-marker{display:none}.faq summary:before{content:'';position:absolute;left:0;top:5px;width:7px;height:25px;background:#789ba9;border-radius:5px}.faq summary:after{content:'＋';font-size:14px;position:absolute;right:0;top:2px;color:var(--blue)}.faq details[open] summary:after{content:'−'}.faq details p{padding-left:0;color:var(--ink);font-size:14px}
.consult{background:#edf3f5;padding:50px 0;margin-top:8px}.consult-grid{display:grid;grid-template-columns:1fr 1fr;gap:45px;align-items:center;width:min(900px,calc(100% - 80px))}.consult h2{font-size:26px;line-height:1.85;color:var(--blue)}.consult p{font-size:13px;margin-top:16px}.button{display:inline-flex;align-items:center;justify-content:center;gap:20px;text-decoration:none;padding:18px 24px;border-radius:4px;background:var(--blue);color:#fff;font-size:14px;line-height:1.8;text-align:center}.button:after{content:'→'}.consult .button{display:flex;width:100%;padding-block:23px}.consult small{display:block;color:var(--sub);font-size:11px;line-height:1.85;margin-top:12px}.consult .timing{margin-top:15px;font-size:14px}.timing strong{font-weight:500}
.references{padding-block:35px 45px}.references h2{font-family:inherit;font-size:13px;font-weight:500}.references ul{padding-left:1.3em;font-size:11px;color:var(--sub)}.references p{font-size:11px;color:var(--sub);line-height:1.9}.footer{border-top:1px solid var(--line);display:flex;justify-content:space-between;gap:30px;padding-block:35px 45px}.footer .logo{font-size:29px}.footer p,.footer small{font-size:11px;color:var(--sub);line-height:2}.related{display:flex;gap:20px;flex-wrap:wrap;margin-top:22px;font-size:12px}.foot-copy{margin-top:13px}.mobile-contact{display:none}
@media(max-width:1060px) and (min-width:761px){.header{grid-template-columns:1fr 155px 190px 145px;column-gap:15px}.desktop-nav a{font-size:10px;padding-left:10px}.desktop-nav a:last-child{padding-inline:10px}.header-phone a{font-size:20px}.header-area{font-size:9px}.article-top{gap:28px}.article-head h1{font-size:22px}}
@media(max-width:760px){
  .wrap{width:calc(100% - 40px)}.reading{width:calc(100% - 40px)}.preview{font-size:9px;padding-block:3px}.header{display:flex;justify-content:space-between;position:relative;min-height:74px;gap:15px}.brand .logo{font-size:31px}.brand small{font-size:8px;margin-top:7px}.header-area,.header-phone,.header-cta,.desktop-nav{display:none}.mobile-nav{display:block}.mobile-nav summary{list-style:none;cursor:pointer;font-size:11px;color:var(--blue);padding:8px 0 8px 10px}.mobile-nav summary::-webkit-details-marker{display:none}.mobile-nav summary span{padding-left:7px}.mobile-nav[open] summary span{display:inline-block;transform:rotate(45deg)}.mobile-nav nav{position:absolute;z-index:20;right:0;top:65px;min-width:190px;background:#fff;border:1px solid var(--line);box-shadow:0 8px 25px #29485315;padding:10px 18px}.mobile-nav nav a{display:block;text-decoration:none;font-size:12px;padding:9px 0;border-bottom:1px solid #edf1f2}.mobile-nav nav a:last-child{border-bottom:0}
  .breadcrumbs{padding:14px 0 17px;gap:5px 9px;font-size:10px;line-height:1.9}.breadcrumbs span:last-child{display:block;flex-basis:100%}.column-banner{height:200px;background-position:center 48%}.column-banner p{font-size:24px;letter-spacing:.12em}.article-top{width:calc(100% - 30px);display:flex;flex-direction:column;gap:18px;margin-top:34px}.article-head{width:100%}.article-date{font-size:11px;margin-bottom:6px}.article-head h1{font-size:22px;line-height:1.85;padding-bottom:17px;letter-spacing:.01em}.article-tag{font-size:10px;margin-top:12px;padding:3px 14px}.byline{font-size:10px;margin-top:11px}.article-picture{width:100%}.article-picture img{aspect-ratio:1.4}.article-picture figcaption{font-size:10px}.intro{padding-top:28px;padding-bottom:36px}.intro p,.intro .answer{font-size:13px;line-height:2.05}.intro .intro-question{font-size:14px;margin-bottom:23px}.intro p+p{margin-top:23px}.toc{width:100%;padding:18px 17px;margin-top:29px}.toc-heading{margin-bottom:13px}.toc ol{font-size:12px}.toc ol ol{font-size:11px}.toc li+li{margin-top:10px}.chapter{padding-bottom:35px}.chapter h2{font-size:21px;line-height:1.8;padding:12px 0 15px;min-height:0;margin-bottom:23px}.chapter h2:after{display:none}.chapter h3{font-size:16px;line-height:1.85;padding-left:20px;margin-block:26px 18px}.chapter h3:before{width:6px;top:5px}.chapter p,.chapter li{font-size:13px;line-height:2.05}.chapter p+p{margin-top:23px}.source{font-size:11px!important}.spec-table{min-width:510px}.table-wrap{margin-top:20px}th,td{padding:12px 10px}.warranty-table th{width:29%}.warranty-table td{font-size:12px}.note{padding:17px 18px;font-size:12px!important}.checklist li{padding:16px 12px 16px 33px}.checklist li:before{left:11px;top:17px}.checklist span{font-size:12px}.inline-link{font-size:12px}.battery-photo{grid-template-columns:138px 1fr;gap:18px;margin-block:24px}.battery-photo figcaption{font-size:11px;line-height:1.9}.battery-photo strong{font-size:22px}.faq summary{font-size:15px;padding-left:20px;padding-right:20px;margin-bottom:13px}.faq summary:before{width:6px;top:4px;height:23px}.faq details p{font-size:13px}.consult{padding-block:35px}.consult-grid{width:calc(100% - 40px);grid-template-columns:1fr;gap:25px}.consult h2{font-size:25px}.consult p{font-size:13px}.consult .button{padding:19px 12px;font-size:13px;gap:12px}.consult small{font-size:10px}.references{padding-block:28px 35px}.references h2{font-size:12px}.references p,.references ul{font-size:10px}.footer{flex-direction:column;gap:24px;padding-bottom:105px}.related{gap:14px;font-size:11px}.mobile-contact{position:fixed;bottom:0;inset-inline:0;z-index:15;display:flex;align-items:center;justify-content:center;padding:9px 15px max(9px,env(safe-area-inset-bottom));background:#ffffffed;border-top:1px solid #dbe4e7;backdrop-filter:blur(10px)}.mobile-contact .button{width:100%;padding:13px 16px;font-size:13px}
}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}

/* Manufacturer product image: retain its original proportions and show the entire panel. */
.product-stage{display:grid;grid-template-columns:.95fr 1.05fr;gap:16px;height:285px;padding:22px;background:linear-gradient(145deg,#f7f9fa,#eaf1f4);align-items:center;overflow:hidden;border:1px solid #e1e9ec}
.article-picture .product-stage .official-panel{display:block;width:100%;height:241px;aspect-ratio:auto;object-fit:contain;padding:0;background:none}
.product-label{min-width:0}.article-picture .product-label img{width:100%;max-width:156px;height:auto;aspect-ratio:auto;object-fit:contain;margin:0 0 25px;padding:0;background:none;mix-blend-mode:multiply}
.product-label span{display:block;font-size:10px;color:var(--sub);line-height:1.8;margin-bottom:8px}.product-label strong{display:block;font:25px/1.5 Georgia,serif;color:var(--blue);letter-spacing:.01em}.product-label small{display:block;font-size:10px;color:var(--sub);line-height:1.8;margin-top:4px;letter-spacing:0}
@media(max-width:760px){.product-stage{height:255px;padding:20px;gap:15px}.article-picture .product-stage .official-panel{height:215px}.article-picture .product-label img{margin-bottom:23px}.product-label strong{font-size:23px}.product-label small{font-size:9px}.product-label span{font-size:9px}}
@media(max-width:360px){.product-stage{padding:17px;gap:12px}.product-label strong{font-size:21px}}

/* Mobile reading review, 2026-10-28: phrase breaks and comfortable text sizes. */
body{overflow-wrap:break-word;word-break:normal}
.heading-phrase{display:inline-block}.nowrap{white-space:nowrap}
.button-label>span{display:block;white-space:nowrap}
.estimate-condition{display:block}
.battery-photo{grid-template-columns:minmax(210px,280px) minmax(0,1fr);gap:32px;align-items:center;padding:24px;background:#f4f7f8;border:1px solid var(--line);border-radius:4px}
.battery-photo img{width:100%;height:auto;aspect-ratio:auto;object-fit:contain;border-radius:3px}
.battery-photo .photo-label{display:block;font-size:12px;color:var(--sub);margin-bottom:10px}
.battery-photo strong{font-size:30px;margin-bottom:14px}
.battery-photo figcaption p{font-size:14px;line-height:1.95;margin:0}
.battery-photo .photo-source{font-size:11px!important;line-height:1.9;margin-top:18px}
.warranty-list{margin:25px 0 0;border:1px solid var(--line);border-radius:4px;overflow:hidden}
.warranty-list>div{display:grid;grid-template-columns:190px 1fr}
.warranty-list>div+div{border-top:1px solid var(--line)}
.warranty-list dt,.warranty-list dd{margin:0;padding:18px;font-size:14px;line-height:1.95}
.warranty-list dt{background:#eef3f5;font-weight:500}
.warranty-list dd{border-left:1px solid var(--line)}
@media(max-width:760px){
 html{scroll-padding-top:20px}
 .reading,.wrap,.article-top{width:calc(100% - 40px)}
 .article-head h1{font-size:clamp(19px,5.5vw,23px);line-height:1.8;letter-spacing:.015em}
 .title-phrase{display:block;white-space:nowrap}
 .article-date{font-size:11px;line-height:1.8}
 .article-picture figcaption{font-size:11px;line-height:1.9}
 .intro{padding-top:32px;padding-bottom:42px}
 .intro p,.intro .answer,.chapter p,.chapter li{font-size:15px;line-height:1.95;letter-spacing:.015em}
 .intro .intro-question{font-size:15px;line-height:1.9;text-wrap:balance}
 .intro p+p,.chapter p+p{margin-top:20px}
 .chapter{padding-bottom:44px}
 .chapter h2{font-size:clamp(19px,5.25vw,22px);line-height:1.8;margin-bottom:24px;padding:10px 0 16px;letter-spacing:.015em}
 .chapter h2>.heading-phrase{display:block}
 .chapter h3{font-size:17px;line-height:1.8;letter-spacing:0;padding-left:17px}
 .toc{padding:22px 18px;margin-top:32px}
 .toc h2{font-size:16px}.toc-toggle{font-size:13px;min-height:40px;padding:5px}
 .toc ol{font-size:14px;line-height:1.95}.toc ol ol{font-size:13px}
 .toc li+li{margin-top:12px}.toc ol ol li+li{margin-top:7px}
 .source{font-size:12px!important;line-height:1.95!important;letter-spacing:.01em}
 .table-tip{font-size:12px!important}.table-wrap{margin-top:16px;border-radius:3px}
 .spec-table{min-width:540px;font-size:13px}.spec-table caption{font-size:12px!important}
 .spec-table th,.spec-table td{padding:14px 12px}
 .checklist li{padding:18px 15px 18px 35px}.checklist li:before{left:12px;top:19px}
 .checklist strong{font-size:15px}.checklist span{font-size:14px;line-height:1.95;margin-top:6px}
 .note{font-size:14px!important;padding:20px 18px;line-height:1.95!important}
 .inline-link{font-size:14px;line-height:1.9;text-wrap:balance}
 .battery-photo{display:block;padding:18px;margin-block:24px;border-radius:5px}
 .battery-photo img{max-width:360px;margin-inline:auto}
 .battery-photo figcaption{margin-top:22px}
 .battery-photo .photo-label{font-size:12px;margin-bottom:7px}
 .battery-photo strong{font-size:28px;margin-bottom:12px}
 .battery-photo figcaption p{font-size:14px;line-height:1.95}
 .battery-photo .photo-source{font-size:12px!important;margin-top:16px}
 .warranty-list{margin-top:20px;border:0;border-radius:0;overflow:visible}
 .warranty-list>div{display:block;border:1px solid var(--line);border-radius:4px;overflow:hidden}
 .warranty-list>div+div{margin-top:14px;border-top:1px solid var(--line)}
 .warranty-list dt{padding:14px 17px;font-size:15px}
 .warranty-list dd{padding:17px;font-size:14px;border-left:0}
 .faq summary{font-size:15px;line-height:1.85;padding-left:17px;padding-right:22px;letter-spacing:0;margin-bottom:14px}
 .faq details{padding-bottom:25px}.faq details p{font-size:15px;line-height:1.95}
 .consult-grid{gap:28px}.consult h2{font-size:clamp(21px,5.8vw,25px);line-height:1.8;letter-spacing:.015em}
 .consult p{font-size:15px;line-height:1.95}
 .consult .button{gap:12px;font-size:14px;line-height:1.8;padding:18px 12px;min-height:78px}
 .consult .timing{font-size:16px;line-height:1.9}
 .consult small{font-size:12px;line-height:1.95;margin-top:14px;letter-spacing:.005em}
 .estimate-condition+.estimate-condition{margin-top:5px}
 .references h2{font-size:14px}.references p,.references ul{font-size:12px;line-height:1.95}
 .references ul{padding-left:1.3em}.references li+li{margin-top:7px}
 .footer p,.footer small{font-size:12px;line-height:1.95}
 .related{font-size:12px;gap:14px}.mobile-contact .button{font-size:14px;min-height:50px}
}
@media(max-width:360px){.chapter h3{font-size:16px}.faq summary{font-size:14px}.brand small{letter-spacing:0}}

.intro p,.chapter p,.faq details p{ text-wrap:pretty }