:root { color-scheme: dark; font-family: "Microsoft YaHei", "Noto Sans SC", system-ui, sans-serif; background: #071a2b; color: #f6fbff; }
* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; background: radial-gradient(circle at 20% 0%, #194d70, #071a2b 55%); }
.presentation { width: min(1500px, 100%); min-height: 100vh; min-height: 100dvh; margin: auto; padding: clamp(18px, 3vw, 42px); display: grid; grid-template-rows: auto 1fr auto auto; gap: 16px; }
.toolbar { display: flex; justify-content: space-between; gap: 24px; align-items: end; }.eyebrow { margin: 0 0 4px; color: #7dd3c7; font-size: .82rem; letter-spacing: .16em; } h1 { margin: 0; font-size: clamp(1.2rem, 2.4vw, 2rem); }.counter { color: #b9d8ee; white-space: nowrap; }
.stage { min-height: 0; display: grid; place-items: center; position: relative; border-radius: 14px; overflow: hidden; background: #000; box-shadow: 0 20px 60px rgba(0,0,0,.38); } #slide-image { display: block; max-width: 100%; max-height: calc(100vh - 250px); object-fit: contain; }
.video-panel { position: absolute; inset: auto 18px 18px; padding: 12px; border-radius: 10px; background: rgba(5,20,34,.9); }.video-panel p { margin: 0 0 8px; } #videos { display: flex; flex-wrap: wrap; gap: 10px; } video { width: min(400px, 100%); max-height: 220px; background: #000; }
.controls { display: flex; flex-wrap: wrap; align-items: center; justify-content: center; gap: 10px; } button, input { font: inherit; } button { border: 1px solid #3b6785; border-radius: 7px; padding: .62rem .9rem; color: #f6fbff; background: #123b59; cursor: pointer; } button:hover, button:focus-visible { background: #1a587d; outline: 2px solid #7dd3c7; outline-offset: 2px; }.jump-label, .hint { color: #c6dfef; }.hint { margin: 0; text-align: center; font-size: .9rem; } #jump { width: 4.2rem; padding: .52rem; color: #fff; background: #09263b; border: 1px solid #3b6785; border-radius: 5px; }
.immersive { overflow: hidden; }
.presentation.immersive { position: fixed; inset: 0; z-index: 1000; width: 100%; height: 100dvh; min-height: 100dvh; padding: max(10px, env(safe-area-inset-top)) max(10px, env(safe-area-inset-right)) max(10px, env(safe-area-inset-bottom)) max(10px, env(safe-area-inset-left)); background: #071a2b; grid-template-rows: auto 1fr auto; gap: 10px; }
.presentation.immersive .hint { display: none; }
.presentation.immersive #slide-image { max-height: calc(100dvh - 145px); }
@media (max-width: 700px) { .presentation { padding: 14px; gap: 10px; } .toolbar { gap: 10px; } .controls { gap: 6px; } .controls button { padding: .55rem .65rem; } .jump-label { display: none; } #slide-image { max-height: calc(100dvh - 220px); } .video-panel { inset: auto 8px 8px; } }