/* AI历史书 sponsorship pages; payment states share the Shenlan presentation contract. */
:root{--ink:#142c3d;--muted:#536b79;--accent-dark:#09665b;--tint:#e2f2eb;--line:#d8e4df;--white:#fff;--bg:#f5f8f5;color-scheme:light}
*{box-sizing:border-box}body{margin:0;color:var(--ink);background:var(--bg);font-family:system-ui,-apple-system,"Microsoft YaHei",sans-serif;line-height:1.6}a{color:var(--accent-dark);text-underline-offset:3px}button,a{-webkit-tap-highlight-color:transparent}button{font:inherit;cursor:pointer}button:disabled{cursor:default;opacity:.5}[hidden]{display:none!important}:focus-visible{outline:3px solid #b27413;outline-offset:4px}h1,h2,h3,p{overflow-wrap:anywhere}h1{font-size:clamp(32px,4vw,48px);line-height:1.25;margin:14px 0 20px;letter-spacing:-.04em}h2{font-size:21px;margin:0 0 12px}p{margin:10px 0 16px}.wrap{width:min(1160px,calc(100% - 40px));margin:0 auto}.site-header{display:flex;gap:18px;align-items:center;justify-content:space-between;padding:18px max(20px,calc((100vw - 1160px)/2));background:var(--white);border-bottom:1px solid var(--line)}.brand{color:var(--ink);font-weight:800;font-size:20px;text-decoration:none;white-space:nowrap}.header-actions{display:flex;gap:10px;align-items:center;flex-wrap:wrap;justify-content:flex-end}.account-button,.button{display:inline-flex;align-items:center;justify-content:center;gap:6px;border:1px solid var(--line);border-radius:9px;background:var(--white);padding:10px 16px;color:var(--ink);font-size:14px;font-weight:600;text-decoration:none;min-height:44px}.button.primary{background:var(--accent-dark);border-color:var(--accent-dark);color:#fff}.button:not(:disabled):hover{filter:brightness(.95)}.button-row{display:flex;align-items:center;flex-wrap:wrap;gap:10px}.skip-link{position:absolute;left:16px;top:6px;z-index:50;background:#fff;padding:8px}.back-link{display:inline-block;margin:28px 0 24px;font-size:14px}.sponsorship-heading{padding:4px 0 12px}.sponsorship-heading>p{font-size:17px;max-width:640px}.sponsor-tiers{list-style:none;display:grid;padding:0;margin:22px 0}.sponsor-tiers li{background:var(--white);border:1px solid var(--line);border-radius:14px;box-shadow:0 8px 24px #142c3d04}.sponsor-tiers li:nth-child(3){border:2px solid var(--accent-dark);background:#f3fbf7}.sponsorship-explainer{border-top:1px solid var(--line);margin:36px 0;padding:28px 0;max-width:850px}.sponsorship-explainer p{color:var(--muted);font-size:14px}.site-footer{padding:30px 0 50px;color:var(--muted);font-size:13px}.site-footer a{margin-right:20px}.text-link{font-size:14px}.payment-note a{white-space:normal}
@media(max-width:600px){.wrap{width:calc(100% - 28px)}.site-header{padding:12px 14px;gap:8px;flex-wrap:wrap}.brand{font-size:18px}.header-actions{gap:6px}.account-button{max-width:140px;font-size:13px;padding:8px 10px}.sponsorship-heading>p{font-size:15px}.back-link{margin:20px 0}.site-footer{padding-bottom:30px}}
.sponsorship-heading{max-width:760px}
.payment-eyebrow{color:var(--accent-dark);font-weight:700;font-size:13px;letter-spacing:.08em}
.payment-steps{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;padding:0;margin:24px 0 32px;list-style:none;counter-reset:steps}
.payment-steps li{display:flex;align-items:center;gap:12px;font-size:14px;line-height:1.6;counter-increment:steps}
.payment-steps li:before{content:counter(steps);display:grid;place-items:center;flex:none;width:32px;height:32px;border-radius:50%;background:var(--tint);color:var(--accent-dark);font-weight:700}
.sponsorship-page .sponsor-tiers{grid-template-columns:repeat(5,minmax(0,1fr));gap:12px}
.sponsorship-page .sponsor-tiers li{display:flex;flex-direction:column;padding:18px 14px;gap:12px;min-width:0}
.payment-tier h3{font-size:14px;font-weight:500;margin:0;color:var(--muted);overflow-wrap:anywhere}
.sponsorship-page .sponsor-tiers b{font-size:28px;line-height:1.3}
.sponsorship-page .sponsor-tiers .payment-tier-points{font-size:16px;margin:0 0 8px;color:var(--accent-dark);font-weight:700}
.payment-tier .button{width:100%;margin-top:auto;white-space:normal;padding:10px 6px;font-size:13px;min-height:44px}
.payment-unavailable{grid-column:1/-1}
.payment-note{font-size:13px;line-height:1.8;color:var(--muted)}
.payment-account{padding:24px;border:1px solid var(--line);background:var(--white);border-radius:12px;margin-top:24px}
.payment-balances{display:grid;grid-template-columns:1fr 1fr;gap:20px;margin:20px 0}
.payment-balances div{display:flex;flex-direction:column;gap:8px;font-size:13px;color:var(--muted)}
.payment-balances strong{font-size:26px;color:var(--ink);font-variant-numeric:tabular-nums}
#payment-status{font-size:14px;line-height:1.8;color:var(--accent-dark);min-height:26px;margin:16px 0 0}
#payment-purchase{display:flex;gap:12px;flex-wrap:wrap;align-items:center}#payment-purchase:empty{display:none}#payment-purchase p{width:100%;font-size:14px;line-height:1.8}
.payment-account .button-row{flex-wrap:wrap}.payment-account .button{min-height:44px}
.sponsorship-membership{margin-top:32px}.sponsorship-page .sponsor-lifetime{min-height:0;margin:0}
@media(max-width:900px){.sponsorship-page .sponsor-tiers{grid-template-columns:repeat(3,minmax(0,1fr))}}
@media(max-width:600px){.payment-steps{grid-template-columns:1fr;gap:12px;margin:20px 0 24px}.sponsorship-page .sponsor-tiers{grid-template-columns:repeat(2,minmax(0,1fr))}.sponsorship-page .sponsor-tiers li{padding:16px 12px}.sponsorship-page .sponsor-tiers b{font-size:25px}.payment-account{padding:18px}.payment-balances{gap:16px}.payment-balances strong{font-size:24px}}
.skip-link:not(:focus){clip-path:inset(100%);pointer-events:none}
.payment-dialog{width:min(480px,calc(100% - 24px));max-height:calc(100dvh - 24px);padding:0;border:1px solid var(--line);border-radius:18px;color:var(--ink);background:var(--white);box-shadow:0 24px 90px #12345c40;overflow:auto}
.payment-dialog::backdrop{background:#10263e99}.payment-dialog-inner{padding:28px;position:relative}.payment-dialog h2{font-size:22px;margin:8px 24px 12px 0;line-height:1.45}.payment-dialog-close{position:absolute;right:12px;top:10px;border:0;background:transparent;font-size:28px;width:40px;height:40px;border-radius:8px;color:var(--muted)}
.payment-dialog-offer{font-size:17px;font-weight:700;line-height:1.7;color:var(--accent-dark)}.payment-qr{width:min(264px,100%);min-height:180px;margin:20px auto;display:grid;place-items:center;text-align:center;background:#fff;color:#24374a;border:1px solid var(--line);border-radius:12px;padding:12px;overflow:hidden}.payment-qr svg{width:100%;height:auto;display:block;fill:initial;stroke:none;shape-rendering:crispEdges}.payment-qr svg path{stroke:none}.payment-credit-success{font-size:22px;font-weight:700;color:var(--accent-dark);line-height:1.8}
#payment-dialog-status{font-size:14px;line-height:1.7}.payment-dialog .button-row{display:flex;flex-wrap:wrap;gap:10px}.payment-dialog .button{min-height:44px;flex:1 1 auto;text-align:center}.payment-dialog .payment-note{margin:14px 0 0}
.payment-orders-page{max-width:1060px;padding-top:24px}.payment-orders-heading{margin:20px 0}.payment-orders-heading h1{font-size:28px;margin:0 0 12px}.payment-orders-controls{display:flex;align-items:center;gap:12px;flex-wrap:wrap;margin:20px 0}.payment-orders-list{list-style:none;padding:0;display:grid;gap:14px}.payment-order{padding:20px;border:1px solid var(--line);border-radius:12px;background:var(--white);overflow-wrap:anywhere}.payment-order h3{font-size:17px;margin:0 0 12px}.payment-order-summary{display:flex;gap:16px;flex-wrap:wrap;align-items:center}.payment-order-summary strong{font-size:20px;color:var(--accent-dark)}.payment-order-status{padding:5px 10px;border-radius:20px;background:var(--tint);font-size:13px}.payment-order p{font-size:13px;color:var(--muted);line-height:1.8;margin:10px 0}.payment-transfers{margin-top:32px;border-top:1px solid var(--line);padding-top:24px}.payment-orders-notice{line-height:1.8;color:var(--muted);font-size:14px}
@media(max-width:600px){.payment-dialog-inner{padding:22px 18px}.payment-dialog h2{font-size:20px}.payment-dialog .button-row{flex-direction:column}.payment-orders-heading h1{font-size:25px}.payment-order{padding:16px}}