:root { color-scheme: dark; font-family: "Microsoft YaHei", system-ui, sans-serif; background: #090d18; color: #eaf6ff; }
* { box-sizing: border-box; }
body { margin: 0; min-height: 100dvh; display: grid; place-items: center; background: radial-gradient(ellipse at 25% 20%, #143b4b80, transparent 60%), radial-gradient(ellipse at 85% 90%, #5c194880, transparent 60%), #090d18; }
#launch-panel { position: relative; max-width: 670px; padding: 40px 24px; text-align: center; }
.brand { font-size: 13px; letter-spacing: .28em; color: #80cdd6; margin: 0 0 30px; }
h1 { font-size: clamp(48px, 10vw, 84px); font-weight: 950; line-height: 1; letter-spacing: -.07em; margin: 0; }
h1 span { color: #69efec; }
.arena { color: #e69edb; font-size: 15px; margin-top: 18px; }
.description { font-size: 19px; margin: 34px 0 24px; }
.actions { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
button, .actions a { font: inherit; font-weight: 700; border-radius: 8px; min-width: 174px; padding: 15px 22px; cursor: pointer; text-decoration: none; }
button { background: #6aece7; color: #071c27; border: 1px solid #93fffa; }
button:disabled { opacity: .55; cursor: wait; }
.actions a { border: 1px solid #536777; color: #cbe3ec; background: #15202e; }
button:focus-visible, a:focus-visible, summary:focus-visible { outline: 3px solid #f1b5e7; outline-offset: 5px; }
#status { min-height: 25px; color: #a9c9d8; font-size: 14px; }
#status.error { color: #ffb0b9; }
progress { width: min(390px, 100%); height: 9px; accent-color: #6aece7; margin-top: 28px; }
.hint, details { font-size: 13px; color: #8b9eaf; line-height: 1.9; margin-top: 24px; }
details p { margin: 8px 0; }
summary { cursor: pointer; }
#canvas { display: none; position: fixed; inset: 0; width: 100%; height: 100%; outline: none; }
body.playing { overflow: hidden; background: #090d18; }
body.playing #canvas { display: block; }
body.playing #launch-panel { display: none; }
[hidden] { display: none !important; }
.file-picker { border: 1px solid #446779; border-radius: 12px; padding: 28px; background: #101c2c; color: #eaf6ff; max-width: min(460px, calc(100vw - 32px)); }
.file-picker::backdrop { background: #030610b8; }
.file-picker h2 { margin: 0 0 16px; font-size: 22px; }
.file-picker p { margin: 0 0 24px; color: #a9c9d8; line-height: 1.7; }
.file-picker button { min-width: 120px; margin-right: 10px; padding: 12px 18px; }
.file-picker button:last-child { background: #203346; border-color: #446779; color: #d0e5ef; }