/* Yu Investudy — Unified Premium Design v2.0, 2026-10-28
   Consistent premium header/footers and warm, understated content surfaces.
   Leaves SEO, article prose, multilingual navigation, PDF and existing routes intact.
   Loaded AFTER legacy/multilingual styles. No web fonts, scripts, trackers or CDN.
*/
:root{--yi-v2-paper:#f7f7f3;--yi-v2-ink:#162c37;--yi-v2-muted:#637982;--yi-v2-line:#dae6df;--yi-v2-teal:#246d69;--yi-v2-gold:#c5a673;}
body.yi-v2-legacy,body.yi-v2-doc{margin:0!important;background:var(--yi-v2-paper)!important;color:var(--yi-v2-ink)!important;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","Noto Sans JP","Noto Sans CJK JP","Noto Sans CJK SC","Noto Sans CJK TC",Meiryo,sans-serif!important;-webkit-font-smoothing:antialiased;}
body.yi-v2-legacy .yi-header,body.yi-v2-doc .yi-header{position:sticky;z-index:200;top:0;border-bottom:1px solid #dce6e2;background:rgba(251,252,250,.95);}
body.yi-v2-legacy .yi-header .yi-brandmark,body.yi-v2-doc .yi-header .yi-brandmark{font-family:Georgia,"Times New Roman",serif;}
/* Legacy pages retain all their original factual and legal content, but get the
   same shared header, full-width dark intro hero, comfortable article rhythm,
   teal/gold accents and full premium footer as Home/Products. */
body.yi-v2-legacy .yi-v2-pagehero{isolation:isolate;}
body.yi-v2-legacy .yi-v2-pagehero .yi-shell{padding-top:85px;padding-bottom:88px;}
body.yi-v2-legacy .yi-v2-pagehero h1{font-weight:730;letter-spacing:-.055em;margin-bottom:18px;}
body.yi-v2-legacy main.yi-v2-main{display:block!important;max-width:1020px!important;width:100%!important;min-height:28vh;margin:0 auto!important;padding:76px 36px 108px!important;background:transparent!important;box-shadow:none!important;border:none!important;color:var(--yi-v2-ink);font-size:15px;line-height:2.05;}
body.yi-v2-legacy main.yi-v2-main :is(.container,.wrap,.wrapper,.content,.inner,.page-content,.page-body){max-width:100%;}
body.yi-v2-legacy main.yi-v2-main :is(h2,h3,h4){color:#1a343e;line-height:1.45;letter-spacing:-.032em;scroll-margin-top:110px;}
body.yi-v2-legacy main.yi-v2-main h2{font-size:clamp(23px,2.45vw,30px);margin:46px 0 19px;padding-bottom:15px;border-bottom:1px solid #dce5e0;font-weight:720;}
body.yi-v2-legacy main.yi-v2-main h3{font-size:20px;margin:32px 0 12px;}
body.yi-v2-legacy main.yi-v2-main p{color:#536a74;font-size:15px;line-height:2.1;}
body.yi-v2-legacy main.yi-v2-main p:first-child{margin-top:0;}
body.yi-v2-legacy main.yi-v2-main a:not(.yi-btn){color:#216e6b!important;text-decoration:underline;text-underline-offset:.2em;text-decoration-thickness:1px;text-decoration-color:#bdd2ca;}
body.yi-v2-legacy main.yi-v2-main a:hover{text-decoration-color:#216e6b;}
body.yi-v2-legacy main.yi-v2-main :is(table){width:100%;border-collapse:collapse;font-size:14px;border-top:1px solid #dce6e1;border-bottom:1px solid #dce6e1;margin:20px 0 35px;}
body.yi-v2-legacy main.yi-v2-main :is(th,td){padding:17px 14px;border-bottom:1px solid #dde8e2;text-align:left;vertical-align:top;line-height:1.75;background:transparent;}
body.yi-v2-legacy main.yi-v2-main th{width:25%;min-width:135px;color:#667b7f;font-weight:700;}
body.yi-v2-legacy main.yi-v2-main :is(hr){border:0;border-top:1px solid #dce6e0;margin:36px 0;}
body.yi-v2-legacy main.yi-v2-main :is(blockquote){border-left:3px solid #c5a673;padding:20px 25px;background:#eef3ef;color:#34515b;border-radius:0 7px 7px 0;}
body.yi-v2-legacy main.yi-v2-main :is(pre){background:#102534;color:#e6f0eb;padding:20px;overflow:auto;border-radius:10px;}
body.yi-v2-legacy main.yi-v2-main :is(.card,.panel,.notice,.callout){border-color:#d7e5de;background-color:#fff;border-radius:14px;box-shadow:0 12px 38px rgba(15,41,47,.045);}
body.yi-v2-legacy main.yi-v2-main :is(.eyebrow,.kicker){color:#2b7874;font-weight:750;letter-spacing:.17em;font-size:11px;text-transform:uppercase;}
body.yi-v2-legacy main.yi-v2-main :is(.button,.btn){border-radius:7px;}
/* Keep the canonical premium header even when legacy style.css targets generic header/nav elements. */
body.yi-v2-legacy .yi-topbar,body.yi-v2-doc .yi-topbar{max-width:1200px;}
body.yi-v2-legacy .yi-nav a,body.yi-v2-doc .yi-nav a{color:#435660;text-decoration:none;}
body.yi-v2-legacy .yi-header-cta,body.yi-v2-doc .yi-header-cta{color:#162c37!important;text-decoration:none!important;}
body.yi-v2-legacy .yi-footer a,body.yi-v2-doc .yi-footer a{color:inherit;text-decoration:none;}
body.yi-v2-legacy .yi-footer a:hover,body.yi-v2-doc .yi-footer a:hover{color:#fff;}
/* Documentation: same brand chrome and dark hero language as the new home,
   while retaining a readable, editorial manual layout and code/table structure. */
body.yi-v2-doc{--mw-ink:#192e38;--mw-muted:#657b81;--mw-bg:#f7f7f3;--mw-card:#fff;--mw-line:#dbe6df;--mw-accent:#256d69;--mw-accent2:#c5a673;}
body.yi-v2-doc .mw-container{max-width:1200px;padding:46px 32px 105px;}
body.yi-v2-doc .mw-breadcrumb{margin-bottom:20px;color:#647980;font-size:12px;letter-spacing:.01em;}
body.yi-v2-doc .mw-breadcrumb a{color:#256c6b!important;text-decoration:underline;text-decoration-color:#b5cac5;text-underline-offset:3px;}
body.yi-v2-doc :is(.mw-hero,.mw-doc-top){position:relative;overflow:hidden;margin:5px 0 35px;padding:52px clamp(24px,4.2vw,58px) 50px;background:radial-gradient(ellipse at 84% 20%,rgba(45,112,103,.32),transparent 62%),linear-gradient(120deg,#0c1d2a,#18343e);color:#f9faf7;border:1px solid rgba(201,172,120,.27);border-radius:19px;box-shadow:0 18px 50px rgba(10,35,45,.12);}
body.yi-v2-doc :is(.mw-hero,.mw-doc-top)::after{content:"";position:absolute;width:280px;height:280px;right:-160px;bottom:-190px;border:1px solid rgba(204,178,126,.34);border-radius:50%;box-shadow:0 0 0 53px rgba(196,164,104,.034);pointer-events:none;}
body.yi-v2-doc :is(.mw-hero,.mw-doc-top) h1{color:#f7faf8!important;letter-spacing:-.045em;line-height:1.3;font-size:clamp(29px,3.6vw,45px);margin:5px 0 15px;}
body.yi-v2-doc :is(.mw-hero,.mw-doc-top) .mw-kicker{color:#dfc490!important;letter-spacing:.18em;font-size:11px;}
body.yi-v2-doc :is(.mw-hero,.mw-doc-top) .mw-lead{max-width:880px;color:#bbced1!important;font-size:16px;line-height:2.0;margin:12px 0 0;}
body.yi-v2-doc .mw-hero{border-bottom:1px solid rgba(201,172,120,.27);}
body.yi-v2-doc .mw-doc-top{border-bottom:1px solid rgba(201,172,120,.27);}
body.yi-v2-doc .mw-cardgrid{gap:23px;}
body.yi-v2-doc .mw-card{background:#fff;border:1px solid #dae6df;border-radius:15px;padding:32px;box-shadow:0 16px 45px rgba(17,47,51,.06);}
body.yi-v2-doc .mw-card h2,body.yi-v2-doc .mw-card h3{font-size:22px;letter-spacing:-.02em;color:#1d3540;}
body.yi-v2-doc .mw-tag{background:#eef4ef;color:#266a65;border:1px solid #dae6df;}
body.yi-v2-doc .mw-button{background:#fff;color:#1f6663;border:1px solid #abc7bd;font-weight:740;text-decoration:none;border-radius:7px;}
body.yi-v2-doc .mw-button.primary{background:#c5a673!important;color:#122b35!important;border-color:#c5a673!important;}
body.yi-v2-doc .mw-button.primary:hover{background:#dbc08d!important;border-color:#dbc08d!important;}
body.yi-v2-doc .mw-button:not(.primary):hover{background:#edf4f0;border-color:#8eafa5;}
body.yi-v2-doc .mw-doc-top .mw-button:not(.primary){background:transparent;color:#edf5f0;border-color:rgba(228,242,238,.44);}
body.yi-v2-doc .mw-doc-top .mw-button:not(.primary):hover{background:rgba(255,255,255,.08);}
body.yi-v2-doc .mw-doc-top .mw-language-strip a{background:rgba(246,249,246,.08);color:#f0f5f1;border:1px solid rgba(220,240,232,.27);}
body.yi-v2-doc .mw-doc-top .mw-language-strip a[aria-current="page"]{background:rgba(195,169,112,.25);border-color:#d0af77;color:#fff;}
body.yi-v2-doc .mw-language-strip a:not([aria-current="page"]):hover{border-color:#c5a673;}
body.yi-v2-doc .mw-langlist{gap:12px;}
body.yi-v2-doc .mw-langlist a{border-radius:9px;border:1px solid #d9e4dc;padding:18px 19px;color:#203943;}
body.yi-v2-doc .mw-langlist a:hover{border-color:#c5a673;background:#fdfcf7;}
body.yi-v2-doc .mw-doc-grid{grid-template-columns:250px minmax(0,1fr);gap:28px;}
body.yi-v2-doc .mw-toc{top:100px;border:1px solid #d9e7df;box-shadow:0 12px 38px rgba(15,41,47,.04);border-radius:14px;}
body.yi-v2-doc .mw-toc a{color:#43636a;text-decoration:none;}
body.yi-v2-doc .mw-toc a:hover{color:#1f706b;text-decoration:underline;}
body.yi-v2-doc .mw-article{background:#fff;border:1px solid #dce7df;box-shadow:0 18px 55px rgba(17,47,51,.053);border-radius:15px;}
body.yi-v2-doc .mw-article :is(h1,h2,h3,h4){color:#173641;scroll-margin-top:110px;}
body.yi-v2-doc .mw-article h2{border-bottom:1px solid #dbe7df;}
body.yi-v2-doc .mw-article a{color:#236e69;text-decoration:underline;text-decoration-color:#c0d4cb;text-underline-offset:2px;}
body.yi-v2-doc .mw-article a:hover{text-decoration-color:#236e69;}
body.yi-v2-doc .mw-article :is(th){color:#244c49;background:#edf4ed;}
body.yi-v2-doc .mw-article tr:nth-child(even) td{background:#fafbf9;}
body.yi-v2-doc .mw-article blockquote{background:#f2f6f1;border-color:#c5a673;}
body.yi-v2-doc .mw-article pre{background:#0f2735;}
body.yi-v2-doc .mw-article :is(.mw-document-name){font-weight:700;}
body.yi-v2-doc .ay-store-card{border:1px solid #dce7df;box-shadow:0 10px 34px rgba(11,31,41,.06);}
body.yi-v2-doc a.ay-store-button{background:#246b68;border-color:#246b68;color:#fff!important;}
body.yi-v2-doc a.ay-store-button:hover{background:#194f4c;}
body.yi-v2-doc .mw-article table{max-width:100%;}
@media(max-width:840px){body.yi-v2-doc .mw-doc-grid{grid-template-columns:1fr;}body.yi-v2-doc .mw-toc{position:static;max-height:none;}body.yi-v2-doc .mw-container{padding:30px 20px 78px;}}
@media(max-width:610px){body.yi-v2-legacy .yi-v2-pagehero .yi-shell{padding-top:60px;padding-bottom:65px;}body.yi-v2-legacy main.yi-v2-main{padding:53px 20px 72px!important;}body.yi-v2-legacy main.yi-v2-main th{min-width:105px;width:36%;}body.yi-v2-legacy main.yi-v2-main :is(th,td){padding:12px 8px;font-size:12px;}body.yi-v2-doc .mw-container{padding:25px 15px 62px;}body.yi-v2-doc :is(.mw-hero,.mw-doc-top){padding:36px 22px;border-radius:13px;}body.yi-v2-doc .mw-card{padding:24px 21px;}}
@media print{body.yi-v2-legacy .yi-header,body.yi-v2-doc .yi-header,body.yi-v2-legacy .yi-footer,body.yi-v2-doc .yi-footer{display:none!important;}body.yi-v2-doc .mw-container{padding:0;}body.yi-v2-doc .mw-doc-top{background:none;color:#172b36;box-shadow:none;border:0;padding:0;}body.yi-v2-doc .mw-doc-top h1{color:#172b36!important;}body.yi-v2-doc .mw-article{box-shadow:none;border:0;}}