:root {
  color-scheme: dark;
  --bg: #0b1018; --surface: #131b27; --surface-hover: #1b293c; --border: #2b384b;
  --text: #f3f6fc; --text-muted: #acb8ca; --accent: #8cb9ff; --accent-hover: #bad5ff;
  --success: #78dcb1; --warning: #e9bc76; --danger: #ffb0b6;
  --radius-sm: 10px; --radius-md: 16px; --radius-lg: 22px;
  --shadow: 0 20px 70px #00000025; --transition: 160ms ease;
}
* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { background: var(--bg); }
body { margin: 0; min-width: 320px; color: var(--text); background: radial-gradient(ellipse 70% 35% at 35% -10%, #203a61 0%, transparent 80%), var(--bg); font: 16px/1.55 Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; }
a { color:inherit; text-underline-offset: 4px; }
button, input, textarea { font: inherit; }
button, a, input, textarea { -webkit-tap-highlight-color: transparent; }
button { cursor: pointer; }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 4px; }
button:disabled { cursor: not-allowed; opacity: .48; }
.sr-only, .clipboard-helper { position: absolute; width: 1px; height: 1px; padding: 0; border:0; overflow: hidden; clip-path: inset(50%); white-space: nowrap; }
.skip-link { position: fixed; top: -100px; left: 16px; z-index: 10; padding: 12px 20px; border-radius:10px; background: var(--accent); color:var(--nk-text); }
.skip-link:focus { top: 12px; }
.topbar { width: min(1180px, calc(100% - 48px)); min-height: 80px; margin: auto; display: flex; align-items: center; justify-content: space-between; gap: 16px; border-bottom:1px solid #ffffff0a; }
.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; font-weight: 750; font-size: 17px; letter-spacing: -.025em; }
.brand-mark { display: grid; place-items: center; width: 30px; height: 30px; border:1px solid #6e97cc66; border-radius:9px; color: var(--accent); font-size: 14px; background:var(--nk-raised); }
.product-name { padding-left: 11px; border-left: 1px solid var(--border); color: var(--text-muted); font-size: 14px; font-weight: 500; letter-spacing: 0; }
.topbar nav a { display: inline-flex; align-items: center; gap: 8px; min-height: 44px; color: var(--text-muted); font-size: 14px; text-decoration: none; }
.topbar a:hover, .site-footer a:hover { color: var(--accent); }
.shell { width: min(1060px, calc(100% - 48px)); margin: auto; }
.intro { padding: 60px 0 36px; }
.eyebrow { margin: 0 0 14px; color: var(--accent); font-size: 11px; font-weight: 750; letter-spacing: .17em; text-transform: uppercase; }
.intro h1 { margin: 0; font-size: clamp(2.5rem, 5vw, 4rem); line-height: 1.05; font-weight: 720; letter-spacing: -.055em; }
.intro h1 span { color: var(--accent); }
.intro > p:last-child { color: var(--text-muted); margin: 18px 0 0; }
.session-bar { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px 20px; margin-bottom: 15px; color: var(--text-muted); font-size: 12px; }
.session-bar strong { color: var(--text); font-variant-numeric: tabular-nums; font-weight: 600; }
.device-status { display: inline-flex; gap: 8px; align-items: center; }
.device-status::before { content: ""; width: 7px; height: 7px; border-radius: 50%; background: var(--warning); }
.device-status[data-state="connected"]::before, .device-status[data-state="ready"]::before, .device-status[data-state="downloaded"]::before { background: var(--success); }
.device-status[data-state="expired"]::before { background: var(--danger); }
.transfer-layout { display: grid; grid-template-columns: minmax(0, 1fr) 340px; gap: 20px; align-items: stretch; }
.transfer-layout.single-panel { grid-template-columns: minmax(0, 1fr); }
.transfer-panel, .share-panel { min-width: 0; border: 1px solid var(--border); border-radius: var(--radius-lg); background: var(--surface); box-shadow: var(--shadow); }
.transfer-panel { padding: 28px; }
.transfer-panel h2 { margin: 0 0 20px; font-size: 20px; font-weight: 650; letter-spacing: -.03em; }
.type-tabs { display: flex; gap: 28px; margin-bottom: 20px; border-bottom: 1px solid var(--border); }
.type-tabs button { position: relative; min-height: 44px; padding: 8px 1px 12px; border:0; background:none; color: var(--text-muted); font-size: 14px; }
.type-tabs button[aria-selected="true"] { color: var(--text); }
.type-tabs button[aria-selected="true"]::after { content: ""; height: 2px; position: absolute; inset: auto 0 -1px; background: var(--accent); }
.transfer-form { display: grid; gap: 15px; }
.transfer-form > label { font-size: 14px; }
input[type="url"], textarea, #session-link { min-width: 0; width: 100%; padding: 13px; border: 1px solid var(--border); border-radius: var(--radius-sm); color: var(--text); background:var(--nk-surface); }
textarea { min-height: 205px; resize: vertical; line-height: 1.5; }
::placeholder { color:var(--nk-muted); opacity: 1; }
.dropzone { min-height: 230px; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 12px; padding: 22px; border:1px dashed var(--nk-line); border-radius: var(--radius-md); background:var(--nk-surface); text-align: center; transition: background var(--transition), border-color var(--transition); }
.dropzone.dragover { background:var(--nk-raised); border-color: var(--accent); }
.drop-icon { width: 45px; height: 45px; color: var(--accent); }
.dropzone strong { font-size: 15px; font-weight: 500; }
.dropzone small { color: var(--text-muted); font-size: 12px; }
.button { display: inline-flex; min-height: 44px; align-items: center; justify-content: center; gap: 12px; padding: 10px 16px; border:1px solid transparent; border-radius: var(--radius-sm); font-size: 14px; font-weight: 650; line-height: 1.4; text-decoration: none; transition: background var(--transition), border-color var(--transition); }
.button.primary { background: var(--accent); color:var(--nk-text); }
.button.primary:hover:not(:disabled) { background: var(--accent-hover); }
.button.secondary { background: var(--surface-hover); border-color:var(--nk-line); color: var(--text); }
.button.secondary:hover:not(:disabled), .button.ghost:hover:not(:disabled) { background:var(--nk-raised); border-color:var(--nk-line); }
.button.ghost { border-color: var(--border); background:transparent; color: var(--text-muted); }
.file-selection { display: flex; gap: 12px; justify-content: space-between; align-items: center; padding: 12px; border: 1px solid var(--border); border-radius: var(--radius-sm); }
.file-selection > div { min-width: 0; }
.file-selection strong { display: block; font-size: 14px; overflow-wrap: anywhere; }
.file-selection span { color: var(--text-muted); font-size: 12px; overflow-wrap: anywhere; }
#upload-progress { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; font-size: 13px; }
progress { flex: 1; min-width: 90px; height: 8px; border:0; border-radius:6px; accent-color: var(--accent); overflow: hidden; }
progress::-webkit-progress-bar { background:var(--nk-raised); }
progress::-webkit-progress-value { background: var(--accent); }
.share-panel { padding: 23px; text-align: center; background:var(--nk-surface); }
.share-heading { display: flex; gap: 10px; align-items: center; text-align: left; margin-bottom: 20px; }
.share-heading h2 { font-size: 14px; line-height: 1.5; font-weight: 600; margin: 0; }
.step-marker { display: grid; place-items: center; width: 29px; height: 29px; flex: none; border:1px solid var(--nk-line); border-radius:50%; color: var(--accent); }
.qr-box { display: grid; place-items: center; aspect-ratio: 1; width: min(100%, 270px); margin: 0 auto 15px; border-radius:14px; padding: 12px; background:white; color:var(--nk-text); font-size: 13px; }
.qr-box svg { display: block; width: 100%; height: auto; }
#share-copy { color: var(--text-muted); font-size: 12px; margin: 12px 0; }
#session-link { padding: 10px; font-size: 11px; text-overflow: ellipsis; }
#copy-link { width: 100%; margin-top: 10px; }
.privacy-note { max-width: 740px; margin: 21px auto 54px; color: var(--text-muted); font-size: 12px; text-align: center; }
.notice { margin: 0 0 18px; border:1px solid var(--nk-line); border-radius: var(--radius-sm); padding: 12px; background:var(--nk-surface); color: var(--danger); font-size: 14px; overflow-wrap: anywhere; }
.muted, .field-hint { color: var(--text-muted); }
.field-hint { font-size: 12px; margin: 0; }
.result-icon { width: 48px; height: 48px; display: grid; place-items: center; margin-bottom: 24px; border:1px solid var(--nk-line); background:var(--nk-surface); color: var(--success); border-radius:50%; font-size: 24px; }
.received h2 { font-size: 28px; margin-bottom: 12px; }
.result-name { margin: 0 0 8px; overflow-wrap: anywhere; font-weight: 600; }
.received-content { max-height: 330px; margin: 20px 0; padding: 16px; overflow: auto; white-space: pre-wrap; overflow-wrap: anywhere; border: 1px solid var(--border); border-radius: var(--radius-sm); background:var(--nk-surface); font: inherit; }
.received-actions { display: flex; flex-wrap: wrap; gap: 10px; margin: 18px 0 14px; }
.new-transfer { margin-top: 28px; }
.site-footer { display: flex; flex-wrap: wrap; gap: 20px; align-items: center; justify-content: space-between; width: min(1180px, calc(100% - 48px)); margin: 0 auto; padding: 22px 0; border-top: 1px solid var(--border); color: var(--text-muted); font-size: 12px; }
.site-footer > a { font-weight: 700; color: var(--text); }
.site-footer nav { display: flex; flex-wrap: wrap; gap: 6px 22px; }
.site-footer a { display: inline-flex; align-items: center; min-height: 44px; text-decoration: none; }
.legal { max-width: 760px; padding: 50px 0 70px; }
.legal h1 { font-size: clamp(28px, 5vw, 42px); letter-spacing: -.04em; }
.legal h2 { margin-top: 30px; font-size: 20px; }
.legal p { color: var(--text-muted); }
@media (max-width: 800px) {
  .intro { padding-top: 40px; }
  .transfer-layout { grid-template-columns: minmax(0, 1fr) 295px; gap: 14px; }
  .transfer-panel { padding: 22px; }
  .share-panel { padding: 18px; }
  .dropzone { padding: 20px 10px; }
}
@media (max-width: 680px) {
  .topbar, .shell, .site-footer { width: calc(100% - 32px); }
  .topbar { min-height: 70px; gap: 8px; }
  .brand { gap: 8px; font-size: 15px; }
  .product-name { font-size: 11px; padding-left: 8px; }
  .topbar nav a { font-size: 12px; }
  .intro { padding: 33px 0 28px; }
  .intro h1 { font-size: clamp(2.4rem, 10vw, 3.6rem); }
  .intro > p:last-child { font-size: 14px; }
  .transfer-layout { grid-template-columns: minmax(0, 1fr); }
  .transfer-panel { padding: 22px 20px; }
  .share-panel { padding: 22px; }
  .share-heading { justify-content: center; }
  .qr-box { width: 237px; }
  .session-bar { font-size: 11px; }
  .privacy-note { margin-bottom: 30px; text-align: left; }
  .site-footer { gap: 4px 15px; }
  .site-footer nav { width: 100%; order: 3; gap: 2px 18px; }
  .site-footer > span { margin-left: auto; }
}
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { animation: none !important; transition: none !important; scroll-behavior: auto !important; } }