:root{--ink:#12243a;--muted:#66798c;--line:#d7e2eb;--blue:#1c63a0;--blue2:#2c7dbb;--orange:#f39a3c;--paper:#fff;--soft:#eef5fa}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:#f4f7fa;color:var(--ink);font:15px/1.68 Inter,"PingFang SC","Microsoft YaHei",sans-serif}a{text-decoration:none;color:inherit}button,input{font:inherit}button,a{transition:transform .16s,box-shadow .16s,opacity .16s}button:not(:disabled):active,a:active{transform:translateY(1px)}button:disabled{cursor:not-allowed;opacity:.44;filter:grayscale(.3)}.wrap{width:min(1160px,calc(100% - 40px));margin:auto}.nav{height:68px;border-bottom:1px solid var(--line);background:#fff}.nav .wrap{height:100%;display:flex;align-items:center;justify-content:space-between}.brand{display:flex;align-items:center;gap:10px;font-weight:900}.brand i{width:36px;height:36px;display:grid;place-items:center;border-radius:9px;background:var(--ink);color:#fff;font-style:normal}.back{padding:8px 13px;border:1px solid #bdccd9;border-radius:8px;color:#285273;font-weight:800}.hero{padding:58px 0;background:radial-gradient(circle at 80% 16%,#d7f4eb 0,transparent 30%),linear-gradient(145deg,#fbfdff,#e8f1f8)}.hero-grid{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(320px,.58fr);align-items:center;gap:52px}.eyebrow{color:var(--blue);font-size:10px;font-weight:900;letter-spacing:.13em}.hero h1{margin:13px 0 15px;font-size:clamp(38px,5vw,62px);line-height:1.08;letter-spacing:-.04em}.hero-copy>p{max-width:720px;color:#536b80;font-size:16px}.hero-actions{margin-top:24px;display:flex;gap:10px;flex-wrap:wrap}.primary,.secondary{min-height:48px;padding:0 19px;display:inline-flex;align-items:center;justify-content:center;border-radius:9px;font-weight:900;cursor:pointer}.primary{border:1px solid var(--blue);background:linear-gradient(135deg,var(--blue),var(--blue2));color:#fff;box-shadow:0 9px 22px rgba(28,99,160,.19)}.secondary{border:1px solid #b8cbd9;background:#fff;color:#255274}.trust-list{margin-top:28px;display:grid;grid-template-columns:repeat(4,1fr);gap:8px}.trust-list span{padding:10px;border:1px solid #d4e1ea;border-radius:8px;background:rgba(255,255,255,.75);color:var(--muted);font-size:10px;text-align:center}.trust-list b{display:block;color:#1d5d8e;font-size:12px}.hero-product{overflow:hidden;border:1px solid #cbd9e4;border-radius:16px;background:#fff;box-shadow:0 22px 48px rgba(19,54,83,.12)}.hero-product img{width:100%;height:260px;display:block;object-fit:cover}.hero-product div{padding:18px}.hero-product span{color:#4f7898;font-size:9px;font-weight:900;letter-spacing:.1em}.hero-product strong{display:block;margin:4px 0;font-size:18px}.hero-product p{margin:0;color:var(--muted);font-size:11px}.store,.login-guide,.warranty,.steps{padding:68px 0}.section-heading{max-width:760px}.section-heading h2{margin:7px 0 8px;font-size:32px;line-height:1.2}.section-heading 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small{display:block;margin-top:4px;color:var(--muted);font-size:10px}.product-login{padding:6px 8px;border-radius:6px;background:#eef3f7;color:#47677f;font-size:9px;font-weight:900;white-space:nowrap}.product-commerce{text-align:right}.product-commerce strong{display:block;color:#154e78;font-size:18px}.product-commerce span{color:#2a805f;font-size:10px;font-weight:900}.product-commerce span.low{color:#b05b2c}.loading-card,.empty-card{padding:45px 20px;text-align:center;color:var(--muted);border:1px dashed #cad7e1;border-radius:10px;background:#f8fafc}.purchase-panel{margin-top:14px;padding:21px;border:1px solid #b9d3e4;border-radius:13px;background:#f7fbfe}.selected-product{display:flex;justify-content:space-between;gap:20px;padding-bottom:16px;border-bottom:1px solid #dce7ef}.selected-product>div:first-child{min-width:0}.selected-product span{color:#3172a2;font-size:9px;font-weight:900}.selected-product h3{margin:4px 0;font-size:22px}.selected-product p{margin:0;color:var(--muted);font-size:11px}.selected-commerce{text-align:right;white-space:nowrap}.selected-commerce strong{display:block;color:#154e78;font-size:25px}.selected-commerce span{color:#2a805f;font-size:10px}.purchase-grid{margin-top:17px;display:grid;grid-template-columns:minmax(0,1fr) minmax(260px,.7fr);gap:14px}.purchase-fields{display:grid;gap:13px}.purchase-fields label>span,fieldset legend{display:block;margin-bottom:6px;color:#526b80;font-size:10px;font-weight:900}.purchase-fields input{width:100%;height:48px;padding:0 13px;border:1px solid #bdcfdd;border-radius:8px;background:#fff;outline:none}.purchase-fields input:focus{border-color:var(--blue);box-shadow:0 0 0 3px rgba(28,99,160,.09)}.purchase-fields small{display:block;margin-top:5px;color:var(--muted);font-size:9px}.purchase-fields small.invalid{color:#b33f32;font-weight:900}fieldset{margin:0;padding:0;border:0}fieldset button{width:calc(50% - 4px);min-height:52px;padding:8px 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article>span{color:#2d6f9f;font-size:9px;font-weight:900;letter-spacing:.07em}.guide-grid h3,.warranty-grid h3{margin:8px 0}.guide-grid p{color:var(--muted);font-size:11px}.guide-grid a,.guide-grid em{display:block;margin-top:13px;color:#1b6399;font-size:10px;font-weight:900;font-style:normal}.warranty-grid{grid-template-columns:1fr 1fr}.warranty-grid article.important{border-color:#e8b779;background:#fffaf2}.warranty-grid ul{margin:10px 0 0;padding-left:18px;color:var(--muted);font-size:11px}.step-grid{margin-top:24px;display:grid;grid-template-columns:repeat(4,1fr);gap:11px}.step-grid article{padding:20px;border:1px solid var(--line);border-radius:11px;background:#fff}.step-grid b{width:29px;height:29px;display:grid;place-items:center;border-radius:50%;background:#1d639d;color:#fff}.step-grid h3{margin:13px 0 5px}.step-grid p{margin:0;color:var(--muted);font-size:10px}.checkout{margin-top:16px;padding:20px;border:1px solid #b9d4e5;border-radius:13px;background:#f5fafe}.checkout-head{display:flex;align-items:center;justify-content:space-between}.checkout-head h3{margin:0}.status{padding:5px 9px;border-radius:999px;background:#fff0d8;color:#96570f;font-size:9px;font-weight:900}.checkout-grid{margin-top:13px;display:grid;grid-template-columns:.9fr 1.1fr;gap:12px}.order-card,.payment-card{padding:17px;border-radius:10px;background:#fff}.order-card dl{margin:0}.order-card dl div{padding:7px 0;display:flex;justify-content:space-between;gap:15px;border-bottom:1px dashed #dfe7ed}.order-card dt{color:var(--muted);font-size:10px}.order-card dd{margin:0;text-align:right;font-weight:850;overflow-wrap:anywhere}.credential{margin-top:11px;padding:10px;border-radius:7px;background:#eff4f7}.credential code{display:block;overflow-wrap:anywhere;font-size:9px}.payment-card h4{margin:0 0 10px}.pay-amount{padding:13px;border-radius:8px;background:#102e48;color:#fff}.pay-amount span{display:block;color:#bed1df;font-size:9px}.pay-amount strong{font-size:23px}.pay-address{margin-top:9px;padding:13px;border:2px solid #2a79b5;border-radius:8px;background:#eef7fc}.pay-address span{color:#2f678d;font-size:9px}.pay-address code{display:block;margin:4px 0;overflow-wrap:anywhere}.payment-methods{display:grid;gap:7px}.payment-method,.balance-pay,.checkout-action{min-height:45px;padding:0 13px;display:flex;align-items:center;justify-content:space-between;border:1px solid #c6d6e2;border-radius:8px;background:#fff;color:#24516f;font-weight:850;cursor:pointer}.payment-method:hover,.balance-pay:hover{border-color:#6ea2c8}.checkout-actions{margin-top:10px;display:flex;gap:7px}.checkout-actions button{flex:1}.copy-btn{min-height:36px;padding:0 12px;border:0;border-radius:6px;background:#72dfb7;color:#123b2e;font-weight:900;cursor:pointer}.checkout-message{padding:20px;border-radius:9px;background:#eef7f3}.checkout-message strong{color:#17674f}.delivery-content{margin-top:10px;padding:12px;border-radius:8px;background:#eff4f7;white-space:pre-wrap;overflow-wrap:anywhere}.checkout-error{padding:11px;border-radius:7px;background:#fff0ed;color:#a63c30}.hidden{display:none!important}footer{padding:25px 0;background:#11293e;color:#bdd0df}footer .wrap{display:flex;justify-content:space-between;gap:15px}footer a{color:#fff}
@media(max-width:900px){.hero-grid{grid-template-columns:1fr}.hero-product{width:min(430px,100%)}.catalog-shell{grid-template-columns:220px minmax(0,1fr)}.guide-grid{grid-template-columns:1fr}.step-grid{grid-template-columns:1fr 1fr}.trust-list{grid-template-columns:1fr 1fr}}
@media(max-width:700px){.wrap{width:min(100% - 24px,1160px)}.nav{height:60px}.hero{padding:32px 0}.hero h1{font-size:36px}.hero-product img{height:210px}.store,.login-guide,.warranty,.steps{padding:46px 0}.section-heading h2{font-size:27px}.catalog-shell{grid-template-columns:1fr}.category-tree{position:static}.category-tree #account-tree{display:grid;grid-template-columns:1fr 1fr;gap:4px}.tree-node{margin-left:0!important;width:100%!important}.product-column{padding:14px}.product-row{grid-template-columns:minmax(0,1fr) auto;gap:9px}.product-login{grid-column:1/2;width:max-content}.product-commerce{grid-row:1/3;grid-column:2}.purchase-grid,.checkout-grid,.warranty-grid{grid-template-columns:1fr}.selected-product{display:block}.selected-commerce{margin-top:8px;text-align:left}.purchase-action{align-items:stretch;flex-direction:column}.purchase-action .primary{width:100%}.step-grid{grid-template-columns:1fr}.checkout-actions{display:grid}.hero-actions .primary,.hero-actions .secondary{width:100%}footer .wrap{flex-direction:column}}
.tree-node.depth-1{margin-left:13px!important;width:calc(100% - 13px)!important}.tree-node.depth-2{margin-left:26px!important;width:calc(100% - 26px)!important}.tree-node.depth-3{margin-left:39px!important;width:calc(100% - 39px)!important}.tree-node.depth-4{margin-left:52px!important;width:calc(100% - 52px)!important}.tree-node.depth-5{margin-left:65px!important;width:calc(100% - 65px)!important}
@media(max-width:700px){.tree-node.depth-1,.tree-node.depth-2,.tree-node.depth-3,.tree-node.depth-4,.tree-node.depth-5{margin-left:0!important;width:100%!important}.tree-node.depth-1 span:before,.tree-node.depth-2 span:before,.tree-node.depth-3 span:before,.tree-node.depth-4 span:before,.tree-node.depth-5 span:before{content:"·"}}

/* Product-first composition and a deliberately prominent login-method hierarchy. */
.hero-grid{grid-template-columns:minmax(320px,.62fr) minmax(0,1.08fr)}
.product-login{min-width:126px;padding:9px 11px;display:flex;flex-direction:column;align-items:flex-start;justify-content:center;border:1px solid #c6d9e7;background:#eef6fb;line-height:1.25}
.product-login small{color:#688095;font-size:8px;letter-spacing:.06em}
.product-login b{margin-top:3px;color:#184f79;font-size:11px}
.selected-product>div:first-child>span:first-child{display:inline-flex;margin-bottom:5px;padding:7px 10px;border:1px solid #a8c9df;border-radius:7px;background:#e9f4fb;color:#164f7a;font-size:11px}
@media(max-width:900px){.hero-grid{grid-template-columns:1fr}.hero-product{order:0}.hero-copy{order:1}}
@media(max-width:700px){.product-login{min-width:0;width:max-content;max-width:100%}.product-login small,.product-login b{display:block}.selected-product>div:first-child>span:first-child{font-size:10px}}
.delivery-item{display:grid;gap:3px;padding:8px 0;border-bottom:1px dashed #cad8e1}.delivery-item:last-child{border-bottom:0}.delivery-item span{color:#60788b;font-size:9px;font-weight:800}.delivery-item code{overflow-wrap:anywhere}.delivery-item a{color:#176ea8;font-weight:900;text-decoration:underline;text-underline-offset:3px}