:root {
  color-scheme: light;
  --ink: #0c2938;
  --muted: #5d7380;
  --paper: #ffffff;
  --line: #d8e8e8;
  --teal: #0aa99d;
  --teal-dark: #087c74;
  --teal-soft: #e8f8f6;
  --deep: #0d3443;
  --shadow: 0 24px 64px rgba(13, 52, 67, 0.12);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  line-height: 1.65;
}
a { color: inherit; text-decoration: none; }
img, video { display: block; max-width: 100%; }
h1, h2, h3, p { margin-top: 0; }

.skip-link {
  position: fixed;
  z-index: 100;
  top: 10px;
  left: 10px;
  padding: 8px 14px;
  color: #fff;
  border-radius: 8px;
  background: var(--deep);
  transform: translateY(-160%);
}
.skip-link:focus { transform: translateY(0); }

.video-header {
  position: sticky;
  z-index: 20;
  top: 0;
  display: flex;
  min-height: 76px;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  padding: 0 clamp(20px, 6vw, 88px);
  border-bottom: 1px solid rgba(216, 232, 232, 0.9);
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(18px);
}
.video-brand { display: flex; align-items: center; gap: 10px; }
.video-brand img { width: 44px; height: 44px; object-fit: cover; object-position: 50% 22%; border-radius: 12px; }
.video-brand span { display: grid; line-height: 1.2; }
.video-brand strong { font-size: 18px; }
.video-brand small { margin-top: 4px; color: var(--muted); font-size: 11px; }
.video-header nav { display: flex; align-items: center; gap: 24px; color: #496474; font-size: 14px; font-weight: 750; }
.video-header nav a:hover,
.video-header nav a:focus-visible,
.video-header nav .is-current { color: var(--teal-dark); }
.video-login { padding: 8px 14px; color: #fff !important; border-radius: 9px; background: var(--teal); }

.video-hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 0.42fr);
  align-items: end;
  gap: clamp(36px, 7vw, 104px);
  padding: clamp(68px, 9vw, 132px) clamp(24px, 7vw, 112px) clamp(64px, 8vw, 112px);
  background:
    radial-gradient(circle at 78% 18%, rgba(40, 201, 188, 0.22), transparent 30%),
    linear-gradient(145deg, #f8fcfc 0%, #edf8f6 62%, #ffffff 100%);
}
.video-hero__copy { max-width: 860px; }
.eyebrow { margin-bottom: 14px; color: var(--teal-dark); font-size: 12px; font-weight: 850; letter-spacing: 0.14em; }
.video-hero h1 { margin-bottom: 24px; font-size: clamp(40px, 4.4vw, 64px); line-height: 1.11; letter-spacing: -0.045em; }
.video-hero__copy > p:not(.eyebrow) { max-width: 720px; color: var(--muted); font-size: 18px; }
.video-hero__facts { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 34px; }
.video-hero__facts span { padding: 8px 12px; color: #426271; border: 1px solid #c9e2e1; border-radius: 999px; background: rgba(255, 255, 255, 0.76); font-size: 13px; }
.video-hero__facts strong { color: var(--teal-dark); }
.video-hero__guide { padding: 30px; color: #fff; border-radius: 24px; background: var(--deep); box-shadow: var(--shadow); }
.video-hero__guide > span { color: #72e3da; font-size: 12px; font-weight: 800; letter-spacing: 0.08em; }
.video-hero__guide strong { display: block; margin: 14px 0 9px; font-size: 23px; line-height: 1.35; }
.video-hero__guide p { color: #c6d9de; font-size: 14px; }
.video-hero__guide a { display: inline-flex; align-items: center; gap: 8px; margin-top: 8px; color: #72e3da; font-weight: 800; }

.video-library { padding: clamp(72px, 8vw, 112px) clamp(24px, 7vw, 112px); }
.library-heading { display: flex; align-items: end; justify-content: space-between; gap: 36px; margin-bottom: 34px; }
.library-heading h2 { margin-bottom: 10px; font-size: clamp(34px, 4vw, 52px); line-height: 1.15; letter-spacing: -0.035em; }
.library-heading > div > p:last-child { margin-bottom: 0; color: var(--muted); }
.video-search { display: grid; width: min(100%, 380px); gap: 7px; color: #486473; font-size: 12px; font-weight: 800; }
.video-search input { width: 100%; min-height: 48px; padding: 0 16px; color: var(--ink); border: 1px solid #badbd8; border-radius: 12px; background: #fff; font: inherit; font-size: 15px; font-weight: 500; outline: none; }
.video-search input:focus { border-color: var(--teal); box-shadow: 0 0 0 4px rgba(10, 169, 157, 0.12); }
.library-status { margin: 0 0 24px; color: var(--muted); }
.library-status:empty { display: none; }
.library-status[data-state="error"] { padding: 16px 18px; color: #8d3f2b; border: 1px solid #efcbbf; border-radius: 12px; background: #fff6f2; }

.video-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 24px; }
.video-card { overflow: hidden; border: 1px solid var(--line); border-radius: 22px; background: #fff; box-shadow: 0 16px 44px rgba(13, 52, 67, 0.08); }
.video-card__media { position: relative; aspect-ratio: 9 / 16; overflow: hidden; background: linear-gradient(145deg, #163f4e, #071f2a); }
.video-card video { width: 100%; height: 100%; object-fit: contain; background: #071f2a; }
.video-card__episode { position: absolute; z-index: 2; top: 14px; left: 14px; padding: 6px 9px; color: #fff; border: 1px solid rgba(255, 255, 255, 0.25); border-radius: 999px; background: rgba(7, 31, 42, 0.78); font-size: 12px; font-weight: 800; backdrop-filter: blur(10px); pointer-events: none; }
.video-card__play { position: relative; width: 100%; height: 100%; padding: 0; overflow: hidden; color: #fff; border: 0; background: radial-gradient(circle at 62% 24%, rgba(54, 218, 204, 0.28), transparent 28%), linear-gradient(155deg, #174b5a, #092632 70%); cursor: pointer; }
.video-card__play::after { position: absolute; inset: 0; content: ""; background: linear-gradient(to top, rgba(5, 25, 34, 0.62), transparent 48%); }
.video-card__play img { width: 100%; height: 100%; object-fit: cover; }
.video-card__play b { position: absolute; z-index: 1; top: 50%; left: 50%; display: grid; width: 64px; height: 64px; place-items: center; padding-left: 4px; border: 1px solid rgba(255, 255, 255, 0.45); border-radius: 50%; background: rgba(255, 255, 255, 0.18); box-shadow: 0 14px 34px rgba(0, 0, 0, 0.22); transform: translate(-50%, -50%); transition: transform 160ms ease, background 160ms ease; backdrop-filter: blur(10px); }
.video-card__play small { position: absolute; z-index: 1; right: 16px; bottom: 16px; left: 16px; color: rgba(255, 255, 255, 0.84); font-size: 12px; font-weight: 750; letter-spacing: 0.08em; }
.video-card__brand { position: absolute; top: 50%; left: 50%; color: rgba(255, 255, 255, 0.1); font-size: clamp(32px, 4vw, 54px); font-weight: 900; letter-spacing: -0.05em; transform: translate(-50%, -50%) rotate(-90deg); }
.video-card__play:hover b,
.video-card__play:focus-visible b { background: var(--teal); transform: translate(-50%, -50%) scale(1.06); }
.video-card__play:focus-visible { outline: 4px solid rgba(10, 169, 157, 0.35); outline-offset: -4px; }
.video-card__body { padding: 20px; }
.video-card__body h3 { min-height: 3em; margin-bottom: 12px; font-size: 18px; line-height: 1.48; }
.video-card__summary { display: -webkit-box; overflow: hidden; margin-bottom: 13px; color: #486473; font-size: 14px; -webkit-box-orient: vertical; -webkit-line-clamp: 3; }
.video-card__date { margin-bottom: 0; color: var(--muted); font-size: 13px; }
.video-empty { grid-column: 1 / -1; padding: 54px 24px; color: var(--muted); border: 1px dashed #b9d8d6; border-radius: 18px; text-align: center; background: #f8fcfc; }

.video-cta { display: flex; align-items: center; justify-content: space-between; gap: 38px; padding: clamp(58px, 7vw, 92px) clamp(24px, 7vw, 112px); background: var(--teal-soft); }
.video-cta h2 { margin-bottom: 12px; font-size: clamp(30px, 4vw, 48px); line-height: 1.2; letter-spacing: -0.035em; }
.video-cta p:last-child { margin-bottom: 0; color: var(--muted); }
.video-cta__actions { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 12px; }
.button { display: inline-flex; min-height: 48px; align-items: center; justify-content: center; padding: 0 21px; border: 1px solid transparent; border-radius: 10px; font-size: 15px; font-weight: 800; }
.button--primary { color: #fff; background: var(--teal); box-shadow: 0 14px 28px rgba(10, 169, 157, 0.2); }
.button--secondary { color: var(--teal-dark); border-color: #a9d9d5; background: #fff; }

footer { display: flex; flex-wrap: wrap; gap: 24px; padding: 32px clamp(24px, 7vw, 112px); color: #617784; border-top: 1px solid var(--line); font-size: 13px; }
footer a:hover { color: var(--teal-dark); }
footer span { margin-left: auto; }

@media (max-width: 1180px) {
  .video-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}

@media (max-width: 900px) {
  .video-header nav a:not(.video-login):not(.is-current) { display: none; }
  .video-hero { grid-template-columns: 1fr; align-items: start; }
  .video-hero__guide { max-width: 560px; }
  .video-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .video-cta { align-items: flex-start; flex-direction: column; }
  .video-cta__actions { justify-content: flex-start; }
}

@media (max-width: 620px) {
  .video-header { min-height: 66px; padding: 0 16px; }
  .video-brand img { width: 38px; height: 38px; }
  .video-header nav { gap: 10px; }
  .video-login { padding: 7px 10px; }
  .video-hero { padding: 54px 18px 64px; }
  .video-hero h1 { font-size: 38px; }
  .video-hero__copy > p:not(.eyebrow) { font-size: 16px; }
  .video-library { padding: 64px 18px; }
  .library-heading { align-items: stretch; flex-direction: column; }
  .video-search { width: 100%; }
  .video-grid { grid-template-columns: 1fr; gap: 20px; }
  .video-card { display: grid; grid-template-columns: minmax(138px, 0.72fr) 1fr; align-items: stretch; }
  .video-card__media { min-height: 250px; }
  .video-card__body { align-self: center; padding: 18px; }
  .video-card__body h3 { min-height: 0; font-size: 17px; }
  .video-cta { padding: 58px 18px; }
  .video-cta__actions, .button { width: 100%; }
  footer { padding: 28px 18px; }
  footer span { width: 100%; margin-left: 0; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .video-card__play b { transition: none; }
}