:root {
  --bg: #101418;
  --panel: rgba(22, 27, 33, 0.92);
  --stroke: rgba(255, 255, 255, 0.08);
  --text: #f5f7fb;
  --muted: #a4afbd;
  --accent: #7ce3cf;
  --accent-strong: #ffb34d;
  --radius: 28px;
  --shadow: 0 30px 90px rgba(0, 0, 0, 0.3);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
  background:
    radial-gradient(circle at top left, rgba(124, 227, 207, 0.14), transparent 24%),
    radial-gradient(circle at bottom right, rgba(255, 179, 77, 0.12), transparent 28%),
    linear-gradient(135deg, #0d1117 0%, #101418 100%);
  color: var(--text);
  font-family: "Space Grotesk", "Segoe UI Variable", sans-serif;
}

body {
  min-height: 100vh;
}

body.drag-active {
  overflow: hidden;
}

input {
  font: inherit;
}

textarea,
button {
  font: inherit;
}

.shell {
  min-height: 100vh;
  width: min(980px, calc(100vw - 32px));
  margin: 0 auto;
  padding: 24px 0;
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 18px;
  align-items: stretch;
}

.panel {
  border-radius: var(--radius);
  border: 1px solid var(--stroke);
  background: var(--panel);
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
  padding: 24px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-height: 340px;
}

.label {
  margin: 0 0 14px;
  color: var(--accent);
  font-size: 0.82rem;
  letter-spacing: 0.24em;
  text-transform: uppercase;
}

.dropzone {
  min-height: 220px;
  border-radius: 24px;
  border: 1px dashed rgba(124, 227, 207, 0.4);
  background:
    radial-gradient(circle at top left, rgba(124, 227, 207, 0.14), transparent 30%),
    rgba(255, 255, 255, 0.03);
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 24px;
  font-size: clamp(1.4rem, 3vw, 2rem);
  letter-spacing: -0.04em;
}

.note-input,
.received-note {
  width: 100%;
  margin-top: 18px;
  border-radius: 22px;
  border: 1px solid rgba(255, 255, 255, 0.09);
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  padding: 18px 20px;
  min-height: 150px;
  resize: vertical;
  line-height: 1.6;
}

.note-input::placeholder {
  color: rgba(245, 247, 251, 0.26);
}

.received-note {
  white-space: pre-wrap;
  word-break: break-word;
}

.note-actions {
  display: flex;
  justify-content: flex-end;
  margin-top: 12px;
}

.note-clear-button {
  min-height: 42px;
  padding: 0 16px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  background: rgba(255, 255, 255, 0.06);
  color: var(--text);
  cursor: pointer;
}

.code-box,
.code-input {
  width: 100%;
  margin-top: 18px;
  border-radius: 22px;
  border: 1px solid rgba(255, 255, 255, 0.09);
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  text-align: center;
  font-size: clamp(2rem, 5vw, 3.6rem);
  letter-spacing: 0.28em;
  padding: 18px 20px;
  min-height: 92px;
}

.code-box {
  display: flex;
  align-items: center;
  justify-content: center;
  font-variant-numeric: tabular-nums;
}

.code-input::placeholder {
  color: rgba(245, 247, 251, 0.26);
}

.status {
  margin: 16px 0 0;
  color: var(--muted);
  line-height: 1.6;
  text-align: center;
}

.copy-button {
  margin-top: 14px;
  min-height: 52px;
  border-radius: 999px;
  border: 1px solid rgba(124, 227, 207, 0.18);
  background: rgba(124, 227, 207, 0.12);
  color: var(--text);
  cursor: pointer;
}

.hidden {
  display: none;
}

.drop-overlay {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  background: rgba(6, 10, 14, 0.78);
  backdrop-filter: blur(18px);
  opacity: 0;
  pointer-events: none;
  transition: opacity 160ms ease;
  z-index: 30;
}

.drop-overlay.visible {
  opacity: 1;
}

.drop-card {
  width: min(720px, 100%);
  border-radius: 30px;
  border: 1px dashed rgba(124, 227, 207, 0.48);
  background:
    radial-gradient(circle at top left, rgba(124, 227, 207, 0.18), transparent 34%),
    rgba(16, 20, 24, 0.94);
  padding: 36px 24px;
  text-align: center;
}

.drop-card h1 {
  margin: 0;
  font-size: clamp(2rem, 5vw, 4rem);
  letter-spacing: -0.06em;
}

@media (max-width: 820px) {
  .shell {
    grid-template-columns: 1fr;
  }

  .panel {
    min-height: 280px;
  }

  .dropzone {
    min-height: 180px;
  }
}