/*
  Концепция: "Ночной курьер". Файл несёт маленький светящийся дух
  (фея) по маршруту телефон -> компьютер, оставляя след из пыльцы.
  Шрифты — системный стек: сайт открывают со случайных компьютеров
  в колледже (та же причина, по которой передача идёт через relay
  :443, а не WebRTC/UDP) — свои шрифты грузить незачем.
  Тема закреплённо тёмная — это "ночь", часть образа.
*/

:root {
  color-scheme: dark;

  --bg-1: #120b26;
  --bg-2: #1f1440;
  --card: rgba(255, 255, 255, 0.05);
  --card-inset: rgba(255, 255, 255, 0.04);
  --border: rgba(255, 255, 255, 0.10);
  --border-strong: rgba(255, 255, 255, 0.18);

  --fg: #f1edf9;
  --fg-muted: #a79bc4;
  --fg-faint: #6b6088;

  --gold: #ffd166;
  --gold-light: #ffe9a8;
  --gold-dim: rgba(255, 209, 102, 0.16);
  --gold-glow: rgba(255, 209, 102, 0.4);
  --pink: #ff8fe3;

  --mint: #6ee7b7;
  --mint-dim: rgba(110, 231, 183, 0.14);
  --coral: #ff6b81;
  --coral-dim: rgba(255, 107, 129, 0.14);

  --radius-lg: 20px;
  --radius-md: 14px;
  --radius-sm: 10px;

  --font-ui: -apple-system, "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "SF Mono", "Cascadia Code", Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  background: radial-gradient(120% 90% at 50% -10%, var(--bg-2), var(--bg-1) 60%);
  color: var(--fg);
  font-family: var(--font-ui);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 32px 16px;
  position: relative;
  overflow-x: hidden;
}

/* starfield */
.stars, .stars::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-repeat: no-repeat;
  background-image:
    radial-gradient(1.6px 1.6px at 8% 22%, #fff, transparent),
    radial-gradient(1.2px 1.2px at 18% 63%, rgba(255,255,255,.8), transparent),
    radial-gradient(1.4px 1.4px at 27% 12%, #fff, transparent),
    radial-gradient(1px 1px at 35% 78%, rgba(255,255,255,.6), transparent),
    radial-gradient(1.8px 1.8px at 44% 34%, #fff, transparent),
    radial-gradient(1.2px 1.2px at 52% 88%, rgba(255,255,255,.7), transparent),
    radial-gradient(1.4px 1.4px at 61% 18%, #fff, transparent),
    radial-gradient(1px 1px at 68% 55%, rgba(255,255,255,.5), transparent),
    radial-gradient(1.6px 1.6px at 76% 8%, #fff, transparent),
    radial-gradient(1.2px 1.2px at 84% 72%, rgba(255,255,255,.8), transparent),
    radial-gradient(1.4px 1.4px at 91% 40%, #fff, transparent),
    radial-gradient(1px 1px at 5% 90%, rgba(255,255,255,.6), transparent),
    radial-gradient(1.3px 1.3px at 95% 15%, rgba(255,255,255,.7), transparent),
    radial-gradient(1px 1px at 40% 6%, rgba(255,255,255,.5), transparent),
    radial-gradient(1.3px 1.3px at 58% 95%, rgba(255,255,255,.6), transparent);
}
.stars { animation: twinkle-a 5s ease-in-out infinite; }
.stars::after { animation: twinkle-b 4s ease-in-out infinite; }
@keyframes twinkle-a { 0%,100% { opacity: 0.9; } 50% { opacity: 0.4; } }
@keyframes twinkle-b { 0%,100% { opacity: 0.5; } 50% { opacity: 1; } }

.moon-glow {
  position: fixed;
  top: -12%; right: -8%;
  width: 480px; height: 480px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255,233,168,0.14), transparent 70%);
  z-index: 0;
  pointer-events: none;
}

@media (prefers-reduced-motion: reduce) {
  .stars, .stars::after { animation: none; }
}

.stage {
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: 460px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
}

/* ---------- brand + idle mascot ---------- */
.brand {
  display: flex;
  align-items: center;
  gap: 8px;
}
.wordmark {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--fg);
}
.wordmark span {
  background: linear-gradient(120deg, var(--gold), var(--pink));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.mascot { width: 34px; height: 34px; animation: bob 3s ease-in-out infinite; transform-origin: center; }
@keyframes bob { 0%,100% { transform: translateY(0); } 50% { transform: translateY(-4px); } }
@media (prefers-reduced-motion: reduce) { .mascot { animation: none; } }

.tagline {
  margin: 0;
  color: var(--fg-muted);
  font-size: 0.9rem;
  text-align: center;
  text-wrap: balance;
}

/* fairy wings flutter (shared) */
.wing { animation: flutter 0.42s ease-in-out infinite alternate; transform-origin: 16px 16px; }
.wing--l { transform-origin: 15px 15px; }
.wing--r { transform-origin: 17px 15px; }
@keyframes flutter { from { transform: scaleX(1); } to { transform: scaleX(0.55); } }
@media (prefers-reduced-motion: reduce) { .wing { animation: none; } }

/* ---------- switcher ---------- */
.switcher {
  position: relative;
  width: 100%;
  display: grid;
  grid-template-columns: 1fr 1fr;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 4px;
  backdrop-filter: blur(12px);
}
.switcher__indicator {
  position: absolute;
  top: 4px; left: 4px;
  width: calc(50% - 4px);
  height: calc(100% - 8px);
  background: linear-gradient(135deg, var(--gold), var(--pink));
  border-radius: calc(var(--radius-md) - 4px);
  transition: transform 0.32s cubic-bezier(0.16, 1, 0.3, 1);
  box-shadow: 0 6px 18px -6px var(--gold-glow);
  z-index: 0;
}
.switcher[data-mode="send"] .switcher__indicator { transform: translateX(100%); }
.switcher__pill {
  position: relative; z-index: 1;
  border: none; background: transparent;
  padding: 12px 10px;
  font: inherit; font-size: 0.92rem; font-weight: 600;
  color: var(--fg-muted);
  cursor: pointer;
  border-radius: calc(var(--radius-md) - 4px);
  transition: color 0.25s;
}
.switcher[data-mode="receive"] .switcher__pill[data-target="receive"],
.switcher[data-mode="send"] .switcher__pill[data-target="send"] { color: #2a1a05; }
.switcher__pill:focus-visible { outline: 2px solid var(--gold-light); outline-offset: 2px; }

/* ---------- card ---------- */
.panel {
  width: 100%;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 26px 24px;
  backdrop-filter: blur(12px);
}
.panel h2 { margin: 0 0 6px; font-size: 1.15rem; font-weight: 700; }
.hint { margin: 0 0 18px; color: var(--fg-muted); font-size: 0.88rem; line-height: 1.5; }
.hint.small { margin: 10px 0 16px; font-size: 0.8rem; }

/* ---------- flight lane ---------- */
.lane {
  position: relative;
  height: 64px;
  margin: 4px 0 18px;
}
.lane__end {
  position: absolute;
  top: 50%; transform: translateY(-50%);
  width: 30px; height: 30px;
  color: var(--fg-muted);
  opacity: 0.85;
}
.lane__end--from { left: 0; }
.lane__end--to { right: 0; }
.lane__track { position: absolute; inset: 0; }
.lane__path {
  stroke: var(--border-strong);
  stroke-width: 1.5;
  stroke-dasharray: 3 6;
  fill: none;
}
.fairy {
  position: absolute;
  top: 0; left: 0;
  width: 30px; height: 30px;
  offset-path: path("M40,50 Q205,-6 370,50");
  offset-distance: 0%;
  offset-rotate: 0deg;
  opacity: 0;
  filter: drop-shadow(0 0 6px var(--gold-glow));
}

/* receive: fixed-duration flourish (fires once we already know the file is ready) */
.fairy.is-flying-auto {
  animation: fly 1.65s cubic-bezier(0.45, 0, 0.4, 1) forwards;
}
@keyframes fly {
  0%   { offset-distance: 0%;   opacity: 0; transform: scale(0.7) rotate(0deg); }
  8%   { opacity: 1; transform: scale(1) rotate(0deg); }
  70%  { offset-distance: 100%; opacity: 1; transform: scale(1) rotate(0deg); }
  79%  { offset-distance: 100%; transform: scale(1.28) rotate(-12deg); }
  87%  { offset-distance: 100%; transform: scale(0.88) rotate(9deg); }
  93%  { offset-distance: 100%; transform: scale(1.06) rotate(-3deg); }
  100% { offset-distance: 100%; opacity: 0; transform: scale(0.85) rotate(0deg); }
}

/* send: position driven by real upload progress (JS sets offset-distance directly) */
.fairy.is-flying-manual { opacity: 1; }
.fairy.is-landing { animation: land-wiggle 0.55s ease-out; }
@keyframes land-wiggle {
  0%   { transform: scale(1) rotate(0deg); }
  30%  { transform: scale(1.28) rotate(-12deg); }
  60%  { transform: scale(0.88) rotate(9deg); }
  85%  { transform: scale(1.06) rotate(-3deg); }
  100% { transform: scale(1) rotate(0deg); }
}

/* sparkle dust (spawned by JS) */
.spark {
  position: fixed;
  width: 5px; height: 5px;
  border-radius: 50%;
  pointer-events: none;
  z-index: 5;
  animation: spark-fade 0.7s ease-out forwards;
}
@keyframes spark-fade {
  0% { opacity: 1; transform: scale(1); }
  100% { opacity: 0; transform: scale(0.2) translateY(6px); }
}
.spark--burst { animation: spark-burst 0.62s ease-out forwards; }
@keyframes spark-burst {
  0%   { opacity: 1; transform: translate(0, 0) scale(1); }
  100% { opacity: 0; transform: translate(var(--dx), var(--dy)) scale(0.25); }
}

/* ---------- code beacon ---------- */
.beacon { display: flex; justify-content: center; gap: 8px; margin: 4px 0 18px; }
.beacon__cell {
  width: 58px; height: 72px;
  display: flex; align-items: center; justify-content: center;
  background: var(--card-inset);
  border: 1px solid var(--gold-dim);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 1.9rem; font-weight: 600;
  color: var(--gold-light);
  text-shadow: 0 0 16px var(--gold-glow);
  animation: beacon-pulse 2.4s ease-in-out infinite;
}
.beacon__cell:nth-child(2) { animation-delay: 0.15s; }
.beacon__cell:nth-child(3) { animation-delay: 0.3s; }
.beacon__cell:nth-child(4) { animation-delay: 0.45s; }
@keyframes beacon-pulse {
  0%, 100% { border-color: var(--gold-dim); }
  50% { border-color: var(--gold); box-shadow: 0 0 20px -4px var(--gold-glow); }
}
@media (prefers-reduced-motion: reduce) {
  .beacon__cell { animation: none; border-color: var(--gold); }
}

/* ---------- status ---------- */
.status {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 10px 16px; border-radius: var(--radius-sm);
  font-size: 0.88rem; font-weight: 600; margin-bottom: 16px;
}
.status--waiting { background: var(--gold-dim); color: var(--gold-light); }
.status--ready   { background: var(--mint-dim); color: var(--mint); }
.status--error   { background: var(--coral-dim); color: var(--coral); }
.status__ring {
  width: 8px; height: 8px; border-radius: 50%;
  background: currentColor;
  animation: ring 1.6s ease-out infinite;
}
@keyframes ring {
  0%   { box-shadow: 0 0 0 0 color-mix(in srgb, currentColor 45%, transparent); }
  70%  { box-shadow: 0 0 0 8px transparent; }
  100% { box-shadow: 0 0 0 0 transparent; }
}
@media (prefers-reduced-motion: reduce) {
  .status__ring { animation: none; }
}

/* ---------- buttons ---------- */
.btn {
  width: 100%; padding: 15px; border-radius: var(--radius-md);
  font: inherit; font-size: 0.96rem; font-weight: 700;
  cursor: pointer; border: none; margin-bottom: 10px;
  transition: transform 0.15s ease, box-shadow 0.25s ease, opacity 0.2s;
}
.btn-primary {
  background: linear-gradient(135deg, var(--gold), var(--gold-light));
  color: #241703;
  box-shadow: 0 10px 24px -10px var(--gold-glow);
}
.btn-primary:hover:not(:disabled) { transform: translateY(-1px); box-shadow: 0 14px 28px -10px var(--gold-glow); }
.btn-primary:active:not(:disabled) { transform: translateY(0) scale(0.98); }
.btn-primary:disabled { opacity: 0.35; cursor: not-allowed; box-shadow: none; }
.btn-primary:focus-visible { outline: 2px solid var(--gold-light); outline-offset: 2px; }

.btn-secondary {
  background: transparent; color: var(--fg-muted);
  border: 1px solid var(--border-strong);
}
.btn-secondary:hover { color: var(--fg); border-color: var(--gold); }
.btn-secondary:focus-visible { outline: 2px solid var(--gold-light); outline-offset: 2px; }

/* ---------- code input ---------- */
.code-input {
  width: 100%; padding: 16px;
  font-family: var(--font-mono); font-size: 1.6rem;
  letter-spacing: 0.35em; text-align: center; text-transform: uppercase;
  background: var(--card-inset); border: 1px solid var(--border-strong);
  border-radius: var(--radius-md); color: var(--fg);
  outline: none; margin-bottom: 16px;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.code-input:focus { border-color: var(--gold); box-shadow: 0 0 0 3px var(--gold-dim); }
.code-input::placeholder { color: var(--fg-faint); letter-spacing: normal; text-transform: none; font-family: var(--font-ui); font-size: 0.85rem; }

/* ---------- drop area ---------- */
.drop {
  border: 1.5px dashed var(--border-strong);
  border-radius: var(--radius-md);
  padding: 28px 18px; text-align: center; cursor: pointer;
  margin-bottom: 16px;
  transition: border-color 0.2s, background 0.2s;
}
.drop:hover, .drop.drag-over { border-color: var(--gold); background: var(--gold-dim); }
.drop__icon { width: 32px; height: 32px; margin: 0 auto 10px; color: var(--gold); }
.drop__text { font-size: 0.92rem; color: var(--fg); margin-bottom: 3px; }
.drop__hint { font-size: 0.78rem; color: var(--fg-faint); }

.file-line {
  background: var(--card-inset); border: 1px solid var(--border);
  border-radius: var(--radius-sm); padding: 12px 14px; margin-bottom: 16px;
  text-align: left; font-size: 0.83rem; color: var(--fg-muted);
  word-break: break-all;
}
.file-line strong { color: var(--fg); }

.progress-text { margin: 0; font-size: 0.85rem; color: var(--fg-muted); text-align: center; }

/* ---------- partner promo (deliberately quieter than the app's own UI) ---------- */
.promo {
  position: relative;
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 10px;
  background: rgba(255, 255, 255, 0.035);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 14px 34px 14px 14px;
}
.promo--pulse { animation: promo-pulse 1.5s ease-out; }
@keyframes promo-pulse {
  0%   { border-color: var(--gold); box-shadow: 0 0 0 0 var(--gold-glow); }
  55%  { box-shadow: 0 0 22px 2px transparent; }
  100% { border-color: var(--border); box-shadow: 0 0 0 0 transparent; }
}
.promo__row { display: flex; align-items: flex-start; gap: 10px; }
.promo__icon { width: 30px; height: 26px; flex: none; margin-top: 2px; color: var(--fg-muted); }
.promo__body { flex: 1; min-width: 0; }
.promo__eyebrow {
  margin: 0 0 3px; font-size: 0.66rem; font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.07em; color: var(--fg-faint);
}
.promo__heading {
  display: flex; align-items: center; flex-wrap: wrap; gap: 8px;
  margin: 0 0 4px;
}
.promo__name { font-size: 0.9rem; font-weight: 700; color: var(--fg); }
.promo__badge {
  font-size: 0.64rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.03em;
  padding: 2px 8px; border-radius: 999px;
  background: var(--gold-dim); color: var(--gold-light);
  border: 1px solid rgba(255, 209, 102, 0.3);
}
.promo__text { margin: 0; font-size: 0.79rem; color: var(--fg-muted); line-height: 1.4; }
.promo__features {
  list-style: none; margin: 6px 0 0; padding: 0;
  display: flex; flex-wrap: wrap; row-gap: 5px; column-gap: 12px;
}
.promo__features li {
  display: flex; align-items: center; gap: 5px;
  font-size: 0.74rem; color: var(--fg-muted);
}
.promo__features svg { width: 11px; height: 11px; flex: none; color: var(--gold); }
.promo__cta {
  align-self: stretch;
  text-align: center;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--border-strong);
  color: var(--fg);
  font-size: 0.82rem;
  font-weight: 700;
  text-decoration: none;
  transition: border-color 0.2s, color 0.2s, background 0.2s;
}
.promo__cta:hover { border-color: var(--gold); color: var(--gold-light); background: var(--gold-dim); }
.promo__cta:focus-visible { outline: 2px solid var(--gold-light); outline-offset: 2px; }
.promo__close {
  position: absolute; top: 8px; right: 8px;
  width: 20px; height: 20px;
  display: flex; align-items: center; justify-content: center;
  border: none; background: transparent; color: var(--fg-faint);
  font-size: 15px; line-height: 1; cursor: pointer; border-radius: 50%;
}
.promo__close:hover { color: var(--fg); background: rgba(255, 255, 255, 0.07); }
.promo__close:focus-visible { outline: 2px solid var(--gold-light); outline-offset: 2px; }

[hidden] { display: none !important; }

@media (max-width: 420px) {
  .beacon__cell { width: 48px; height: 60px; font-size: 1.5rem; }
  .panel { padding: 20px 16px; }
}