:root{color-scheme:dark;--bg:#0b1118;--panel:#151f2a;--panel2:#1d2b39;--line:#334354;--ink:#f6f4ee;--muted:#b9c8d5;--accent:#ffb264;--focus:#ffcf89;font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--ink);line-height:1.6}a{color:inherit;text-decoration:none}a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid var(--focus);outline-offset:3px}button,input,select{font:inherit}button{cursor:pointer}.wrap{width:min(1160px,calc(100% - 36px));margin:auto}.skip{position:absolute;left:-9999px;top:0;background:white;color:black;padding:12px;z-index:30}.skip:focus{left:10px}.site-head{position:sticky;top:0;z-index:20;background:#0b1118f5;border-bottom:1px solid var(--line);backdrop-filter:blur(12px)}.head-inner{display:flex;align-items:center;justify-content:space-between;gap:16px;min-height:72px}.brand{display:inline-flex;align-items:center;gap:10px;font-weight:850;font-size:1.08rem;letter-spacing:-.03em;white-space:nowrap}.mark{width:35px;height:35px;border-radius:50%;background:radial-gradient(circle at 35% 30%,#607589,#172536 60%,#070b10 100%);position:relative;flex:none;box-shadow:0 0 0 2px #435568}.mark:before{content:'••';position:absolute;top:-3px;left:10px;color:#050a10;font-size:20px;letter-spacing:2px;transform:rotate(-20deg)}.mark:after{content:'•';position:absolute;top:9px;left:11px;color:#050a10;font-size:19px}.brand em{font-style:normal;color:var(--accent)}.nav{display:flex;gap:5px;align-items:center}.nav a{padding:11px 13px;border-radius:12px;color:var(--muted);font-size:.94rem;font-weight:650}.nav a:hover,.nav a[aria-current=page]{background:#233242;color:white}.menu-toggle{display:none;border:1px solid var(--line);background:var(--panel);color:white;border-radius:12px;padding:9px 13px;font-weight:700}.eyebrow{color:var(--accent);text-transform:uppercase;letter-spacing:.19em;font-size:.76rem;font-weight:800}.hero{padding:clamp(58px,8vw,110px) 0 65px;position:relative;overflow:hidden;background:radial-gradient(ellipse at 78% 35%,#243a4c 0%,transparent 48%),linear-gradient(145deg,#101a25,#0b1118)}.hero-grid{display:grid;grid-template-columns:1.3fr .7fr;gap:45px;align-items:center}.hero h1{font-size:clamp(2.65rem,6.5vw,5.8rem);line-height:1.04;letter-spacing:-.065em;margin:15px 0 20px;max-width:790px}.hero p,.lead{font-size:clamp(1.06rem,2vw,1.27rem);color:var(--muted);max-width:670px}.actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:28px}.btn{display:inline-flex;justify-content:center;align-items:center;min-height:48px;padding:12px 19px;border-radius:13px;font-weight:750;border:1px solid #526578;background:transparent;color:#fff}.btn.primary{background:var(--accent);border-color:var(--accent);color:#10151c}.btn:hover{transform:translateY(-1px);filter:brightness(1.1)}.orb{aspect-ratio:1;max-width:330px;width:100%;margin:auto;border-radius:50%;background:radial-gradient(circle at 30% 25%,#64768a 0%,#243648 35%,#101821 68%,#04070a 100%);box-shadow:inset -25px -30px 50px #0008,0 45px 65px #0008;position:relative;transform:rotate(-20deg)}.orb i{position:absolute;width:12%;height:12%;border-radius:50%;background:#03070b;box-shadow:inset 4px 4px 7px #000;top:29%;left:37%}.orb i:nth-child(2){left:54%;top:34%}.orb i:nth-child(3){left:42%;top:47%}.section{padding:65px 0}.section.alt{background:#101923}.section-head{display:flex;justify-content:space-between;align-items:end;gap:16px;margin-bottom:25px}.section h2,.page-title{font-size:clamp(2rem,4.4vw,3.4rem);line-height:1.13;letter-spacing:-.045em;margin:10px 0}.section-intro{color:var(--muted);max-width:670px}.text-link{color:var(--accent);font-weight:750}.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.card{border:1px solid var(--line);background:var(--panel);border-radius:18px;padding:23px;display:flex;flex-direction:column;min-height:210px;transition:transform .2s,border-color .2s}.card:hover{transform:translateY(-3px);border-color:#d99b5c}.card h3{font-size:1.28rem;line-height:1.25;margin:12px 0 8px}.card p{color:var(--muted);margin:0 0 16px}.card .foot{margin-top:auto;color:var(--accent);font-weight:750}.iconbox{width:45px;height:45px;border-radius:13px;background:#263748;color:var(--accent);display:grid;place-items:center;font-size:1.35rem}.pill{display:inline-block;color:var(--accent);font-size:.74rem;font-weight:800;text-transform:uppercase;letter-spacing:.08em}.ball-card{padding:0;overflow:hidden;min-height:0}.ball-art{height:160px;background:radial-gradient(circle at 50% 110%,#2c4254,#121c27 68%);display:grid;place-items:center;position:relative}.ball-art:before{content:'';display:block;width:116px;height:116px;border-radius:50%;background:radial-gradient(circle at 30% 25%,var(--ball-light,#6f8192),var(--ball-dark,#142334) 68%,#070b11);box-shadow:12px 18px 26px #0008}.ball-art:after{content:'••';position:absolute;left:calc(50% - 13px);top:calc(50% - 25px);color:#080d12;font-size:18px;letter-spacing:3px;transform:rotate(-15deg)}.ball-body{padding:19px;display:flex;flex-direction:column;flex:1}.ball-body h3{margin:7px 0}.ball-body p{font-size:.93rem}.ball-body .foot{margin-top:auto}.small{font-size:.88rem;color:var(--muted)}.banner{padding:57px 0 34px;background:linear-gradient(145deg,#172534,#0d141c)}.banner .lead{margin:12px 0}.breadcrumbs{font-size:.86rem;color:var(--muted);margin-bottom:22px}.breadcrumbs a{color:var(--accent)}.filters{display:flex;gap:12px;flex-wrap:wrap;margin:25px 0}.field{background:#182532;color:white;border:1px solid #637386;border-radius:12px;padding:13px 14px;min-height:49px}.field.search{flex:1;min-width:220px}.field.select{min-width:190px}.count{color:var(--muted);font-size:.93rem;margin:0 0 15px}.exhibit{display:grid;grid-template-columns:minmax(0,1.5fr) minmax(260px,.65fr);gap:34px;align-items:start}.prose{max-width:760px}.prose p{color:#d8e1e9;font-size:1.07rem;line-height:1.86;margin:0 0 21px}.fact-panel{border:1px solid var(--line);border-radius:18px;background:var(--panel);padding:22px}.fact-panel dl{margin:0}.fact-panel dt{font-size:.75rem;color:var(--accent);font-weight:800;text-transform:uppercase;letter-spacing:.08em;margin-top:15px}.fact-panel dd{margin:3px 0 0;font-weight:600}.notice{border-left:3px solid var(--accent);background:#1c2935;padding:17px 20px;border-radius:0 12px 12px 0;color:var(--muted);font-size:.93rem;margin-top:30px}.placeholder{border:1px dashed #607183;border-radius:16px;background:#162330;padding:27px;text-align:center;color:var(--muted)}.placeholder strong{color:#fff}.footer{border-top:1px solid var(--line);padding:35px 0 50px;color:var(--muted);font-size:.88rem}.footer-inner{display:flex;justify-content:space-between;gap:18px;flex-wrap:wrap}.footer a{color:var(--accent)}.muted{color:var(--muted)}.notfound{padding:75px 0}.detail-photo{height:230px;border-radius:16px;background:radial-gradient(circle at 50% 85%,#30485d,#101923 70%);display:grid;place-items:center;margin-bottom:18px}.detail-photo .orb{max-width:160px}.empty{border:1px solid var(--line);border-radius:14px;padding:22px;color:var(--muted)}
@media(max-width:850px){.hero-grid{grid-template-columns:1fr}.hero-visual{display:none}.grid{grid-template-columns:repeat(2,minmax(0,1fr))}.exhibit{grid-template-columns:1fr}.fact-panel{order:-1}.section{padding:48px 0}}@media(max-width:640px){.wrap{width:calc(100% - 32px)}.head-inner{min-height:64px}.brand{font-size:1rem}.menu-toggle{display:block;min-height:44px}.nav{display:none;position:absolute;top:63px;left:0;right:0;background:#101a25;padding:10px 16px 16px;flex-direction:column;align-items:stretch;border-bottom:1px solid var(--line);box-shadow:0 15px 30px #0007}.nav.open{display:flex}.nav a{min-height:46px;display:flex;align-items:center;padding:10px 13px}.hero{padding:58px 0}.hero h1{font-size:clamp(2.75rem,12vw,4.1rem)}.hero p{font-size:1.05rem}.grid{grid-template-columns:1fr}.card{min-height:0}.section-head{display:block}.actions{flex-direction:column}.actions .btn{width:100%}.filters{flex-direction:column}.field.search,.field.select{width:100%}.ball-art{height:130px}.ball-art:before{width:94px;height:94px}.banner{padding:35px 0 24px}.section{padding:38px 0}.prose p{font-size:1rem;line-height:1.75}.footer-inner{flex-direction:column}.fact-panel{padding:18px}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{scroll-behavior:auto!important;transition:none!important;animation:none!important}}

/* Temporary external reference photos; fall back to original illustrations on load failure. */
.ball-art.has-photo:before,.ball-art.has-photo:after{display:none}
.ball-art img{width:100%;height:100%;object-fit:contain;display:block;padding:9px;background:#101923}
.detail-photo.has-photo{height:auto;aspect-ratio:1;background:#101923;overflow:hidden}
.detail-photo.has-photo img{width:100%;height:100%;object-fit:contain;display:block}
@media(max-width:640px){.ball-art.has-photo{height:205px}}

/* v1.3: responsive technology library and article galleries */
.topic-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:15px}
.topic-card{min-width:0;display:flex;flex-direction:column;align-items:flex-start;gap:9px;background:var(--panel);border:1px solid var(--line);border-radius:19px;padding:22px;transition:border-color .15s,transform .15s}
.topic-card:hover,.article-card:hover{border-color:var(--accent);transform:translateY(-2px)}
.topic-card h2{font-size:1.22rem;letter-spacing:-.02em;line-height:1.25;margin:3px 0 0}
.topic-card p{font-size:.94rem;line-height:1.55;color:var(--muted);margin:0 0 9px}
.topic-card .foot,.article-card .foot{margin-top:auto;color:var(--accent);font-weight:750}
.topic-icon{display:grid;place-items:center;width:49px;height:49px;border-radius:14px;background:#27394a;color:var(--accent);font-size:1.55rem}
.article-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}
.article-card{display:flex;flex-direction:column;min-width:0;overflow:hidden;background:var(--panel);border:1px solid var(--line);border-radius:20px;transition:border-color .15s,transform .15s}
.article-card-body{padding:20px;display:flex;flex-direction:column;flex:1}
.article-card h3{font-size:1.4rem;line-height:1.25;margin:12px 0 10px}
.article-card p{color:var(--muted);margin:0 0 20px;line-height:1.6}
.article-art{height:210px;position:relative;overflow:hidden;display:grid;place-items:center;background:radial-gradient(circle at 73% 20%,#42647c,transparent 54%),linear-gradient(140deg,#23374a,#101923)}
.article-art:before{content:'';position:absolute;width:170px;height:170px;border:2px solid #ffffff24;border-radius:50%;box-shadow:0 0 0 35px #ffffff08,0 0 0 75px #ffffff05}
.art-glyph{font-size:5.5rem;line-height:1;color:#ffbe77;text-shadow:0 12px 28px #0008;z-index:1}
.art-label{position:absolute;bottom:12px;left:16px;color:#d1dfeb;letter-spacing:.13em;font-size:.63rem;font-weight:800}
.art-pinsetters{background:linear-gradient(135deg,#344455,#121d2a)}.art-ball-returns{background:linear-gradient(135deg,#254b55,#101d29)}.art-lane-conditioning{background:linear-gradient(135deg,#253f67,#101827)}.art-lanes{background:linear-gradient(135deg,#55422d,#181d27)}.art-scoring{background:linear-gradient(135deg,#3a315b,#171b2c)}.art-bowling-pins{background:linear-gradient(135deg,#604039,#1c2029)}.art-other-technology{background:linear-gradient(135deg,#354b49,#141d25)}
.reading-layout{display:grid;grid-template-columns:minmax(0,1fr) 270px;gap:30px;align-items:start}
.article-prose{max-width:780px}.article-prose .article-art{border-radius:20px;margin-bottom:26px;height:300px}
.article-prose p{font-size:1.12rem;line-height:1.86;color:#dbe5ed;margin:0 0 22px}
.article-aside h2{font-size:1.15rem;margin:10px 0}.article-aside p{color:var(--muted)}
.museum-bridge{margin-top:34px;padding:25px;border-radius:19px;border:1px solid #846446;background:linear-gradient(120deg,#332b26,#182330);display:flex;justify-content:space-between;gap:22px;align-items:center}
.museum-bridge h2{margin:8px 0}.museum-bridge p{color:var(--muted);margin:0}
@media(max-width:1020px){.topic-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.article-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:720px){.reading-layout{grid-template-columns:1fr}.article-aside{display:none}.museum-bridge{flex-direction:column;align-items:stretch}.museum-bridge .btn{width:100%}}
@media(max-width:640px){.topic-grid,.article-grid{grid-template-columns:1fr}.topic-card{padding:20px;min-height:0}.topic-card p{font-size:1rem}.article-art{height:200px}.article-prose .article-art{height:215px}.article-prose p{font-size:1.04rem;line-height:1.75}.article-card h3{font-size:1.36rem}.article-card-body{padding:20px}.topic-card,.article-card{border-radius:16px}}

/* v1.4 historical scoring feature */
.article-card-image{width:100%;height:210px;object-fit:cover;display:block;background:#17283a}
.scoring-intro{font-size:1.23rem!important;color:#fff!important;border-left:3px solid var(--accent);padding-left:19px}
.history-chapter{margin-bottom:48px}.history-chapter h2,.scoring-sources h2{font-size:clamp(1.55rem,3vw,2.15rem);line-height:1.25;letter-spacing:-.025em;margin:0 0 22px;color:#fff}.history-chapter p{margin-bottom:18px}.history-figure{margin:28px 0 34px}.history-figure img{display:block;width:100%;max-height:510px;object-fit:contain;background:#172331;border:1px solid var(--line);border-radius:15px}.history-figure figcaption{color:var(--muted);font-size:.86rem;line-height:1.5;margin-top:9px}.history-figure figcaption a,.scoring-sources a{color:var(--accent);text-decoration:underline;text-underline-offset:3px}.scoring-sources{padding-top:30px;border-top:1px solid var(--line)}.scoring-sources h3{font-size:1.2rem;margin:28px 0 12px}.scoring-sources ol{padding-left:24px}.scoring-sources li{padding:0 0 17px 6px;overflow-wrap:anywhere}.scoring-sources li span{display:block;color:var(--muted);font-size:.92rem;margin-top:3px}.research-note{font-size:.95rem!important;color:var(--muted)!important;margin-top:24px!important}@media(max-width:640px){.history-chapter{margin-bottom:34px}.history-figure{margin:22px 0 27px}.article-card-image{height:200px}}