:root {
  color-scheme: dark;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: #0d1220;
  color: #f4f7fb;
  --panel: #151d2d;
  --panel-border: #27344d;
  --muted: #9eabc1;
  --accent: #58d6a4;
  --accent-strong: #2fb882;
}

* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; background: radial-gradient(circle at 20% 0%, #1d2d4a 0, #0d1220 42%); }
button, input { font: inherit; }
button { cursor: pointer; border: 0; }
.shell { width: min(720px, calc(100% - 32px)); margin: 0 auto; padding: 48px 0 28px; }
.brand { display: flex; align-items: center; gap: 14px; margin-bottom: 28px; }
.brand-mark { width: 48px; height: 48px; display: grid; place-items: center; border-radius: 14px; color: #08140f; background: var(--accent); font-weight: 900; letter-spacing: -0.08em; }
h1, h2, p { margin-top: 0; }
h1 { margin-bottom: 3px; font-size: 28px; }
h2 { margin-bottom: 10px; font-size: 22px; }
.brand p, .muted, footer, .status { color: var(--muted); }
.notice, .card { border: 1px solid var(--panel-border); border-radius: 20px; background: rgba(21, 29, 45, .92); box-shadow: 0 22px 60px rgba(0, 0, 0, .2); }
.notice { padding: 15px 18px; margin-bottom: 18px; color: #c6d0df; line-height: 1.5; }
.notice strong { color: var(--accent); }
.card { padding: 24px; margin-bottom: 18px; }
.mode-actions { display: grid; gap: 12px; grid-template-columns: repeat(2, minmax(0, 1fr)); }
.card-heading { display: flex; align-items: flex-start; justify-content: space-between; gap: 20px; }
.eyebrow { color: var(--accent); font-size: 12px; font-weight: 800; letter-spacing: .12em; text-transform: uppercase; }
.primary, .secondary, .danger { width: 100%; border-radius: 12px; padding: 13px 16px; font-weight: 800; }
.primary { color: #07150f; background: var(--accent); }
.primary:hover { background: #78e4ba; }
.primary:disabled { cursor: not-allowed; opacity: .45; }
.secondary { color: #eaf0f8; background: #26334b; border: 1px solid #3b4a67; }
.secondary:hover { background: #30415e; }
.danger { margin-top: 16px; color: #ffc6c6; background: #402232; border: 1px solid #73384d; }
.compact { width: auto; padding: 9px 12px; font-size: 13px; }
.link-button { color: var(--accent); background: transparent; font-weight: 700; }
.code { margin: 18px 0 12px; padding: 16px; border-radius: 14px; color: var(--accent); background: #0b111e; text-align: center; font-size: 38px; font-weight: 900; letter-spacing: .2em; }
label { display: block; margin: 18px 0 8px; color: #ccd5e2; font-size: 14px; font-weight: 700; }
input { width: 100%; padding: 14px; border: 1px solid #41516d; border-radius: 12px; outline: none; color: #fff; background: #0c1321; font-size: 24px; letter-spacing: .2em; text-align: center; }
input:focus { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(88, 214, 164, .14); }
.status { min-height: 24px; margin: 14px 0; }
.preview, .remote-video { display: block; width: 100%; max-height: 390px; margin-top: 18px; border-radius: 14px; background: #080c14; object-fit: contain; }
.transfer-tools { margin-top: 20px; padding: 16px; border: 1px solid #2d3c57; border-radius: 14px; background: #101827; }
.transfer-tools h3 { margin: 0 0 14px; font-size: 16px; }
.transfer-tools input[type="file"] { width: 100%; margin-bottom: 10px; color: var(--muted); font-size: 13px; letter-spacing: normal; text-align: left; }
.transfer-tools textarea { width: 100%; resize: vertical; padding: 12px; border: 1px solid #41516d; border-radius: 10px; outline: none; color: #fff; background: #0c1321; }
.transfer-tools textarea:focus { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(88, 214, 164, .14); }
.inline-actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 8px; }
footer { display: flex; justify-content: space-between; gap: 12px; padding: 4px 4px; font-size: 12px; }
.hidden { display: none; }
@media (max-width: 560px) { .shell { padding-top: 24px; } .mode-actions { grid-template-columns: 1fr; } .card { padding: 18px; } .code { font-size: 30px; } footer { flex-direction: column; } }