:root{--theme:#0B3D91;--ink:#14213d;--muted:#667085;--line:#e5e7eb;--soft:#f5f7fb;--white:#fff;--accent:#d41468}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;color:var(--ink);background:#fff;font-family:-apple-system,BlinkMacSystemFont,"Noto Sans JP","Hiragino Kaku Gothic ProN",Meiryo,sans-serif;line-height:1.7}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
button{font:inherit}
.container{width:min(1180px,calc(100% - 40px));margin:0 auto}
.topbar{background:#101827;color:#dbe4f4;font-size:12px}
.topbar-inner{min-height:34px;display:flex;align-items:center;justify-content:space-between;gap:20px}
.topbar-contact{display:flex;gap:20px}
.topbar a:hover{color:#fff}
.header{position:relative;z-index:30;background:#fff;border-bottom:1px solid var(--line)}
.header-inner{min-height:78px;display:flex;align-items:center;gap:30px}
.logo{display:inline-flex;align-items:center;gap:10px;white-space:nowrap;font-weight:800;font-size:18px;color:var(--ink)}
.logo img{width:34px;height:34px;object-fit:contain}
.main-nav{flex:1}
.nav-list{display:flex;align-items:center;justify-content:center;gap:4px;margin:0;padding:0;list-style:none}
.nav-item{position:relative}
.nav-link{display:flex;align-items:center;min-height:78px;padding:0 13px;font-size:14px;font-weight:700;cursor:pointer}
.nav-link:hover,.nav-item:focus-within>.nav-link{color:var(--theme)}
.has-panel>.nav-link:after{content:"⌄";font-size:12px;margin-left:5px;color:#98a2b3}
.dropdown-panel,.mega-menu{position:absolute;top:100%;left:50%;transform:translateX(-50%);visibility:hidden;opacity:0;pointer-events:none;background:#fff;border:1px solid var(--line);box-shadow:0 18px 45px rgba(16,24,40,.14);transition:.2s ease}
.dropdown-panel{width:290px;padding:18px}
.mega-menu{width:min(850px,calc(100vw - 32px));padding:22px}
.nav-item:hover>.dropdown-panel,.nav-item:focus-within>.dropdown-panel,.nav-item:hover>.mega-menu,.nav-item:focus-within>.mega-menu{visibility:visible;opacity:1;pointer-events:auto}
.dropdown-panel:before,.mega-menu:before{content:"";position:absolute;left:0;right:0;top:-12px;height:12px}
.dropdown-list{display:grid;gap:10px}
.dropdown-list a{font-size:13px;padding-bottom:8px;border-bottom:1px solid var(--line)}
.panel-entry{display:flex;justify-content:space-between;margin-top:14px;color:var(--theme);font-size:13px;font-weight:700}
.mega-heading{display:flex;justify-content:space-between;align-items:center;gap:15px;margin-bottom:16px}
.mega-heading strong{font-size:16px}
.mega-heading a,.mega-heading span{font-size:12px;color:var(--muted)}
.mega-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}
.mega-card{display:flex;gap:10px;padding:11px;border:1px solid var(--line);border-radius:10px;background:#fff;min-width:0}
.mega-card img{width:48px;height:48px;object-fit:cover;border-radius:7px;background:var(--soft);flex:0 0 auto}
.mega-card span{min-width:0}
.mega-card strong{display:block;font-size:13px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.mega-card p{margin:3px 0;font-size:11px;color:var(--muted);display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.mega-card small{display:block;color:var(--muted);font-size:10px;line-height:1.45}
.mega-categories{display:flex;flex-wrap:wrap;gap:7px;margin-bottom:16px}
.mega-categories a{padding:5px 10px;border-radius:20px;background:var(--soft);font-size:12px}
.header-btns{display:flex;align-items:center;gap:12px;font-size:12px;white-space:nowrap}
.header-btns>a{padding:9px 14px;border-radius:7px;background:var(--theme);color:#fff;font-weight:700}
.hamburger{display:none;width:42px;height:42px;border:1px solid var(--line);border-radius:8px;background:#fff;padding:9px;cursor:pointer}
.hamburger span{display:block;height:2px;margin:5px 0;background:var(--ink);transition:.2s}
.hamburger.active span:nth-child(1){transform:translateY(7px) rotate(45deg)}
.hamburger.active span:nth-child(2){opacity:0}
.hamburger.active span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}
.drawer-overlay{position:fixed;inset:0;background:rgba(15,23,42,.48);opacity:0;visibility:hidden;transition:.25s;z-index:60}
.drawer-overlay.open{opacity:1;visibility:visible}
.mobile-drawer{position:fixed;top:0;right:0;width:min(390px,90vw);height:100vh;overflow:auto;background:#fff;transform:translateX(105%);transition:.28s;z-index:70;box-shadow:-15px 0 40px rgba(0,0,0,.16)}
.mobile-drawer.open{transform:translateX(0)}
.drawer-head{display:flex;align-items:center;gap:12px;padding:20px;border-bottom:1px solid var(--line);font-weight:800}
.drawer-head span{flex:1}
.drawer-head a{padding:7px 11px;background:var(--theme);border-radius:6px;color:#fff;font-size:12px}
.drawer-close{border:0;background:transparent;font-size:28px;line-height:1;cursor:pointer}
.drawer-menu{padding:10px 20px 30px}
.drawer-link,.drawer-toggle{display:block;width:100%;padding:14px 0;border:0;border-bottom:1px solid var(--line);background:transparent;text-align:left;font-weight:700;cursor:pointer}
.drawer-toggle:after{content:"＋";float:right;color:var(--muted)}
.drawer-toggle.active:after{content:"−"}
.drawer-submenu{display:none;padding:3px 0 8px 16px}
.drawer-submenu.open{display:block}
.drawer-submenu a{display:block;padding:8px 0;color:var(--muted);font-size:13px}
.footer{margin-top:80px;padding:54px 0 22px;background:#101827;color:#d7dfed}
.footer-grid{display:grid;grid-template-columns:1.5fr 1fr 1fr 1fr;gap:38px}
.footer .logo{color:#fff}
.footer-brand p{max-width:350px;color:#9eabc0;font-size:13px}
.footer h2{margin:0 0 15px;color:#fff;font-size:14px}
.footer-links,.footer-contact{display:grid;gap:8px}
.footer-links a,.footer-contact a{color:#aebbd0;font-size:13px}
.footer-links a:hover,.footer-contact a:hover{color:#fff}
.footer-social{margin-top:8px;color:#aebbd0}
.footer-bottom{display:flex;justify-content:space-between;gap:20px;margin-top:38px;padding-top:18px;border-top:1px solid rgba(255,255,255,.13);color:#8997ad;font-size:11px}
.video-detail-main{padding:48px 0 0;background:linear-gradient(180deg,#f7f9fc 0,#fff 420px)}
.video-detail-main .breadcrumb{display:flex;gap:8px;align-items:center;margin-bottom:22px;color:var(--muted);font-size:12px}
.video-detail-main .breadcrumb a{color:var(--theme)}
.video-detail-main .video-heading{max-width:860px;margin:0 auto 26px;text-align:center}
.video-detail-main h1{margin:0 0 15px;font-size:clamp(28px,4vw,48px);line-height:1.25;letter-spacing:-.03em}
.video-detail-main .video-meta{display:flex;justify-content:center;flex-wrap:wrap;gap:10px 22px;color:var(--muted);font-size:13px}
.video-stage{width:min(1000px,100%);margin:0 auto;padding:12px;background:#0c1220;border-radius:16px;box-shadow:0 22px 55px rgba(15,23,42,.2)}
.video-player{aspect-ratio:16/9;display:grid;place-items:center;overflow:hidden;border-radius:10px;background:#172238}
.video-player iframe,.video-player video{width:100%;height:100%;border:0}
.video-player img{width:100%;height:100%;object-fit:cover;opacity:.72}
.video-playmark{position:absolute;display:grid;place-items:center;width:74px;height:74px;border-radius:50%;background:var(--accent);color:#fff;font-size:30px;padding-left:5px;box-shadow:0 8px 25px rgba(212,20,104,.4)}
.video-content-wrap{width:min(1000px,100%);margin:32px auto 0;display:grid;grid-template-columns:minmax(0,1fr) 280px;gap:32px}
.video-summary,.video-body,.related-videos{background:#fff;border:1px solid var(--line);border-radius:14px;padding:25px}
.video-summary h2,.video-body h2,.related-videos h2{margin:0 0 12px;font-size:18px}
.video-summary p{margin:0;color:#475467}
.video-body{margin-top:20px;min-width:0;max-width:100%;overflow-x:auto}
.video-body img,.video-body table{max-width:100%}
.video-tags{display:flex;flex-wrap:wrap;gap:8px;margin-top:20px}
.video-tags a{padding:5px 10px;border-radius:20px;background:#eef3fb;color:var(--theme);font-size:12px}
.related-videos{height:max-content}
.related-list{display:grid;gap:14px}
.related-card{display:grid;grid-template-columns:90px 1fr;gap:10px}
.related-card img{width:90px;height:62px;object-fit:cover;border-radius:7px;background:var(--soft)}
.related-card strong{display:block;font-size:12px;line-height:1.45}
.related-card small{color:var(--muted);font-size:11px}
.more-videos{display:inline-flex;margin-top:18px;color:var(--theme);font-size:13px;font-weight:700}
@media(max-width:1050px){.nav-link{padding:0 8px}.header-inner{gap:12px}.footer-grid{grid-template-columns:repeat(2,1fr)}}
@media(max-width:820px){.main-nav{display:none}.hamburger{display:block}.header-btns>span{display:none}.topbar-inner{padding:7px 0;align-items:flex-start}.topbar-contact{flex-direction:column;gap:0}.header-inner{min-height:68px}.video-content-wrap{grid-template-columns:1fr}.footer{margin-top:55px}}
@media(max-width:560px){.container{width:min(100% - 28px,1180px)}.topbar{font-size:10px}.mega-grid{grid-template-columns:1fr}.footer-grid{grid-template-columns:1fr;gap:25px}.footer-bottom{display:grid}.video-detail-main{padding-top:30px}.video-detail-main h1{font-size:28px}.video-stage{padding:7px;border-radius:10px}.video-summary,.video-body,.related-videos{padding:18px}}