:root { --blue: #2f7ab6; --blue-dark: #256391; --teal: #25b7b2; --ink: #2c3a45; --muted: #647b8b; --line: #e4edf2; --page: #f2f7fa; --shadow: 0 8px 32px rgba(42, 74, 97, .045); }
body { background: var(--page); color: var(--ink); font-size: 14px; line-height: 1.65; }
.svg-library { position: absolute; width: 0; height: 0; overflow: hidden; }
.icon { width: 20px; height: 20px; flex: 0 0 auto; fill: none; stroke: currentColor; stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round; }
.skip-link { position: fixed; left: 20px; top: -100px; background: white; padding: 12px; z-index: 100; }
.skip-link:focus { top: 10px; }
.site-header { background: rgba(255,255,255,.96); border-bottom: 1px solid var(--line); }
.header-inner { max-width: 1408px; min-height: 84px; margin: auto; padding: 0 48px; display: flex; align-items: center; gap: 24px; }
.brand img { width: 88px; height: auto; }
.header-divider { height: 22px; width: 1px; background: #dbe5ed; }
.header-label { color: var(--muted); font-size: 13px; font-weight: 500; letter-spacing: .045em; }
.header-nav { margin-left: auto; display: flex; gap: 30px; align-items: center; font-size: 12px; font-weight: 600; }
.home-link, .contact-link { display: inline-flex; align-items: center; gap: 10px; }
.home-link { color: var(--muted); }
.home-link .icon { width: 14px; height: 14px; }
.home-link:hover { color: var(--blue); }
.contact-link { background: var(--blue); color: white; padding: 11px 21px; border-radius: 30px; box-shadow: 0 4px 10px #2f7ab612; }
.contact-link .icon { width: 16px; height: 16px; }
.contact-link:hover { background: var(--blue-dark); }
.page-shell { width: min(1280px, calc(100% - 96px)); margin: auto; }
.breadcrumb { display: flex; flex-wrap: wrap; align-items: center; gap: 11px; padding: 25px 0 0; color: #778c9b; font-size: 11px; }
.breadcrumb .icon { width: 11px; height: 11px; color: #9db0bd; }
.breadcrumb [aria-current] { color: #405767; }
.breadcrumb a:hover { color: var(--blue); }
.page-intro { padding: 36px 0 33px; display: flex; gap: 24px; align-items: center; justify-content: space-between; }
.eyebrow { display: flex; align-items: center; gap: 9px; font-family: Arial, sans-serif; letter-spacing: .16em; color: var(--blue); font-size: 10px; font-weight: 700; margin-bottom: 12px; }
.eyebrow > span { display: block; height: 3px; width: 24px; border-radius: 3px; background: linear-gradient(90deg, var(--blue), var(--teal)); }
h1 { font-size: clamp(24px, 2.4vw, 33px); letter-spacing: .035em; font-weight: 700; line-height: 1.5; }
h1 span { color: var(--blue); }
.intro-description { color: var(--muted); font-size: 12px; margin-top: 11px; letter-spacing: .015em; }
.mobile-break { display: none; }
.intro-badge { display: flex; align-items: center; gap: 15px; padding: 16px 23px; border: 1px solid #e0ebf1; background: #ffffffa8; border-radius: 14px; }
.intro-badge > .icon { color: var(--blue); width: 29px; height: 29px; stroke-width: 1.4; }
.intro-badge strong { display: block; font-size: 12px; font-weight: 600; }
.intro-badge div > span { display: block; color: var(--muted); margin-top: 3px; font-size: 11px; }
.learning-layout { display: grid; grid-template-columns: minmax(0, 1fr) 340px; align-items: start; gap: 25px; }
.watch-column { min-width: 0; }
.player-card, .curriculum-card { background: white; border: 1px solid var(--line); box-shadow: var(--shadow); border-radius: 18px; overflow: hidden; }
.player-toolbar { display: flex; align-items: center; justify-content: space-between; padding: 15px 22px; }
.toolbar-label { display: flex; align-items: center; gap: 9px; font-size: 11px; color: #506879; font-weight: 600; }
.status-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--teal); }
.current-position { font-family: Arial, sans-serif; font-size: 10px; letter-spacing: .1em; color: #8294a1; }
.video-stage { background: #101820; aspect-ratio: 16/9; }
.videoBox { width: 100%; height: 100%; object-fit: contain; background: #101820; }
.video-message { background: #fff5e7; padding: 12px 24px; color: #76511b; font-size: 12px; }
.video-details { padding: 23px 25px 20px; }
.detail-heading { display: flex; align-items: center; gap: 15px; }
.detail-number { display: grid; place-items: center; flex: 0 0 43px; height: 43px; border-radius: 12px; background: #edf5fb; color: var(--blue); font-family: Arial, sans-serif; font-size: 19px; font-weight: 600; }
.detail-category { font-size: 10px; color: var(--muted); margin-bottom: 3px; }
.detail-heading h2 { font-size: 18px; font-weight: 700; line-height: 1.6; overflow-wrap: anywhere; }
.fullscreen-button { margin-left: auto; align-self: center; flex: 0 0 34px; height: 34px; display: grid; place-items: center; border: 1px solid var(--line); border-radius: 9px; background: white; color: #6d8494; }
.fullscreen-button:hover { color: var(--blue); background: #edf5fb; }
.fullscreen-button .icon { width: 16px; height: 16px; }
.lesson-navigation { display: flex; align-items: center; justify-content: space-between; border-top: 1px solid var(--line); padding-top: 19px; margin-top: 23px; gap: 10px; }
.lesson-navigation button { display: inline-flex; align-items: center; justify-content: center; gap: 14px; min-height: 39px; padding: 9px 17px; border-radius: 8px; font-size: 11px; font-weight: 600; }
.previous-button { background: white; color: #526c7e; border: 1px solid #dce6ed; }
.previous-button:hover:not(:disabled) { background: #f2f7fa; }
.previous-button:disabled { color: #a6b2bc; border-color: #edf1f4; }
.next-button { background: var(--blue); color: white; border: 1px solid var(--blue); }
.next-button:hover:not(:disabled) { background: var(--blue-dark); }
.next-button:disabled { opacity: .4; }
.lesson-navigation .icon { width: 15px; height: 15px; }
.reverse { transform: rotate(180deg); }
.navigation-count { font-family: Arial, sans-serif; font-size: 11px; font-weight: 600; color: var(--blue); letter-spacing: .06em; }
.navigation-count span { color: #9aaab5; font-weight: 400; margin-left: 5px; }
.viewing-note { display: flex; gap: 10px; color: #647d8f; padding: 18px 6px; font-size: 11px; line-height: 1.9; }
.viewing-note > .icon { width: 16px; height: 16px; margin-top: 3px; color: #7c96a9; }
.viewing-note p span { color: #8295a3; font-size: 10px; }
.curriculum-heading { display: flex; align-items: center; justify-content: space-between; padding: 23px 23px 19px; border-bottom: 1px solid var(--line); }
.section-kicker { font: 700 9px Arial, sans-serif; letter-spacing: .14em; color: #849aab; margin-bottom: 7px; }
.curriculum-heading h2 { font-size: 17px; letter-spacing: .035em; }
.total-badge { background: #eef5fa; color: #587b95; border-radius: 6px; padding: 4px 9px; font-size: 10px; }
.lesson-list { list-style: none; padding: 9px; }
.lesson-list li + li { margin-top: 3px; }
.lesson { position: relative; width: 100%; display: flex; align-items: center; text-align: left; gap: 11px; padding: 12px 12px; border: 1px solid transparent; border-radius: 10px; color: var(--ink); background: white; min-height: 63px; transition: background .15s, border-color .15s; }
.lesson:hover { background: #f4f8fb; }
.lesson-number { width: 27px; flex: 0 0 27px; color: #8ba0af; font-family: Arial, sans-serif; font-size: 12px; font-weight: 600; align-self: flex-start; margin-top: 2px; text-align: center; }
.lesson-copy { display: block; flex: 1; min-width: 0; }
.lesson-title { display: block; font-size: 11px; font-weight: 600; line-height: 1.8; overflow-wrap: anywhere; }
.lesson-state { display: block; color: #8b9ca9; font-size: 9px; margin-top: 3px; font-weight: 400; }
.lesson-play { width: 13px; height: 13px; color: #aabac7; stroke-width: 1.4; }
.lesson.is-active { background: #eef9f8; border-color: #daefec; }
.lesson.is-active::before { content: ''; position: absolute; height: 25px; width: 3px; background: var(--teal); left: -1px; top: calc(50% - 12.5px); border-radius: 0 3px 3px 0; }
.lesson.is-active .lesson-number, .lesson.is-active .lesson-title { color: #197a81; }
.lesson.is-active .lesson-state { color: #258c91; }
.lesson.is-active .lesson-play { fill: var(--teal); stroke: var(--teal); }
.curriculum-footer { display: flex; align-items: center; justify-content: center; gap: 7px; font-size: 9px; color: #8197a6; background: #fbfdfe; border-top: 1px solid var(--line); padding: 14px 10px; }
.curriculum-footer .icon { width: 13px; height: 13px; }
.support-strip { display: flex; gap: 20px; align-items: center; border: 1px solid #deebf1; border-radius: 15px; background: linear-gradient(110deg, #eaf3f9, #eff9f7); padding: 26px 30px; margin: 32px 0 48px; }
.support-icon { width: 45px; height: 45px; flex: 0 0 auto; display: grid; place-items: center; border-radius: 13px; background: #ffffffb8; color: var(--blue); }
.support-icon .icon { width: 23px; height: 23px; }
.support-strip h2 { font-size: 16px; letter-spacing: .03em; }
.support-strip p { font-size: 11px; color: var(--muted); margin-top: 5px; }
.support-strip > a { margin-left: auto; display: inline-flex; align-items: center; flex: 0 0 auto; gap: 24px; background: white; color: var(--blue); border: 1px solid #d5e5ef; padding: 11px 19px; border-radius: 8px; font-size: 11px; font-weight: 600; }
.support-strip > a:hover { border-color: var(--blue); }
.support-strip > a .icon { width: 15px; height: 15px; }
.site-footer { background: white; border-top: 1px solid var(--line); }
.footer-inner { display: flex; align-items: center; gap: 20px; max-width: 1376px; padding: 25px 48px; margin: auto; }
.footer-inner img { width: 67px; height: auto; }
.footer-tagline { font-size: 10px; color: #889aa7; }
.privacy-link { margin-left: auto; font-size: 10px; color: #6c8293; }
.footer-inner small { font-size: 9px; color: #8e9eaa; }
@media (min-width: 1500px) { .page-intro { padding-top: 44px; padding-bottom: 37px; } }
@media (max-width: 1100px) { .header-inner { padding: 0 32px; } .page-shell { width: calc(100% - 64px); } .learning-layout { grid-template-columns: minmax(0, 1fr) 300px; gap: 20px; } .intro-badge { padding: 14px; } h1 { font-size: 27px; } .footer-tagline { display: none; } }
@media (max-width: 850px) { .learning-layout { grid-template-columns: minmax(0, 1fr); } .intro-badge { display: none; } .curriculum-card { margin-top: 2px; } .lesson { min-height: 65px; } .lesson-title { font-size: 13px; } .lesson-state { font-size: 10px; } .lesson-number { width: 32px; flex-basis: 32px; } .viewing-note p { font-size: 0; } .viewing-note p::before { content: '確認したい操作を動画一覧から選択してください。'; font-size: 11px; } .viewing-note p span { display: block; } .support-strip { margin-top: 26px; } }
@media (max-width: 600px) { .header-inner { min-height: 70px; padding: 0 20px; gap: 14px; } .brand img { width: 74px; } .header-label { font-size: 10px; } .header-divider { height: 18px; } .home-link { display: none; } .header-nav { gap: 0; } .contact-link { padding: 8px 11px; font-size: 10px; } .contact-link .icon { display: none; } .page-shell { width: calc(100% - 36px); } .breadcrumb { font-size: 9px; gap: 7px; padding-top: 20px; } .page-intro { padding: 28px 0 25px; } .eyebrow { font-size: 9px; margin-bottom: 11px; } h1 { font-size: 24px; line-height: 1.6; letter-spacing: .01em; } h1 span { display: block; } .intro-description { font-size: 11px; line-height: 1.9; margin-top: 10px; } .mobile-break { display: block; } .player-card, .curriculum-card { border-radius: 13px; } .player-toolbar { padding: 12px 16px; } .video-details { padding: 18px 16px 16px; } .detail-heading { gap: 11px; } .detail-number { height: 37px; flex-basis: 37px; border-radius: 9px; font-size: 17px; } .detail-heading h2 { font-size: 15px; } .fullscreen-button { flex-basis: 30px; height: 30px; } .lesson-navigation { margin-top: 18px; padding-top: 16px; } .lesson-navigation button { padding: 9px 12px; gap: 10px; } .viewing-note { padding: 15px 2px; gap: 7px; } .viewing-note p::before { font-size: 10px; } .viewing-note p span { font-size: 9px; } .curriculum-heading { padding: 20px; } .lesson { padding: 12px 11px; } .lesson-title { font-size: 12px; } .curriculum-footer { font-size: 10px; } .support-strip { flex-wrap: wrap; padding: 22px 20px; gap: 12px; margin-bottom: 30px; } .support-strip > div:nth-child(2) { flex: 1; } .support-strip h2 { font-size: 14px; } .support-strip p { font-size: 10px; } .support-strip > a { margin: 4px 0 0; width: 100%; justify-content: space-between; } .support-icon { width: 38px; height: 38px; } .footer-inner { padding: 22px 20px; flex-wrap: wrap; gap: 16px; } .privacy-link { font-size: 9px; } .footer-inner small { display: block; width: 100%; } }
@media (prefers-reduced-motion: reduce) { * { scroll-behavior: auto !important; transition: none !important; } }

/* Compact layout for embedding in the official website. */
.page-shell { padding-top: 8px; padding-bottom: 32px; }

/* Match desktop player and curriculum card heights. */
@media (min-width: 851px) {
  .learning-layout { align-items: stretch; }
  .watch-column { display: flex; }
  .player-card { display: flex; flex-direction: column; width: 100%; }
  .player-toolbar, .video-details, .video-message { flex: 0 0 auto; }
  .video-stage { position: relative; flex: 1 0 auto; }
  .video-stage .videoBox { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: contain; }
}