* {
  box-sizing: border-box;
}
:root {
  --bg1: radial-gradient(
      1200px 800px at 20% 10%,
      rgba(116, 137, 255, 0.2),
      transparent 60%
    ),
    radial-gradient(
      1000px 600px at 90% 10%,
      rgba(255, 116, 190, 0.18),
      transparent 60%
    ),
    radial-gradient(
      900px 700px at 50% 90%,
      rgba(94, 255, 206, 0.18),
      transparent 60%
    ),
    #0b0f1a;
  --card: rgba(255, 255, 255, 0.06);
  --stroke: rgba(255, 255, 255, 0.15);
  --text: #e8eeff;
  --muted: #b9c3e6;
  --accent: #7aa2ff;
  --accent2: #ff79c6;
  --glow: 0 0 22px rgba(122, 162, 255, 0.45), 0 0 44px rgba(255, 121, 198, 0.22);
}

html,
body {
  height: 100%;
}
body {
  margin: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Inter,
    Arial, sans-serif;
  color: var(--text);
  background: var(--bg1);
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  border-bottom: 1px solid var(--stroke);
  backdrop-filter: blur(8px);
}
h1 {
  margin: 0;
  font-size: 24px;
  text-shadow: var(--glow);
}
h1 .by {
  font-weight: 400;
  opacity: 0.9;
}
.actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}
button,
.file-btn {
  background: linear-gradient(
    135deg,
    rgba(122, 162, 255, 0.15),
    rgba(255, 121, 198, 0.12)
  );
  color: var(--text);
  border: 1px solid var(--stroke);
  padding: 10px 14px;
  border-radius: 14px;
  cursor: pointer;
  box-shadow: var(--glow);
  font-weight: 600;
}
button.primary {
  background: linear-gradient(
    135deg,
    rgba(122, 162, 255, 0.25),
    rgba(255, 121, 198, 0.22)
  );
}
button.ghost {
  background: transparent;
}
.file-btn span {
  pointer-events: none;
}

.workspace {
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: 16px;
  padding: 16px;
}
@media (max-width: 900px) {
  .workspace {
    grid-template-columns: 1fr;
  }
  .controls {
    order: 2;
  }
  .stage {
    order: 1;
  }
}

.controls {
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.card {
  background: var(--card);
  border: 1px solid var(--stroke);
  border-radius: 16px;
  padding: 14px;
  box-shadow: var(--glow);
}
.card h3 {
  margin: 0 0 8px 0;
  font-size: 16px;
}
.control {
  margin: 10px 0;
}
.control label {
  display: block;
  color: var(--muted);
  margin-bottom: 6px;
}
.control small {
  opacity: 0.8;
}
.row {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}
.ink {
  flex: 1;
}
.ink.sel {
  outline: 2px solid var(--accent);
}

.stage {
  display: flex;
  align-items: center;
  justify-content: center;
}
.canvas-wrap {
  position: relative;
  width: min(100%, 1100px);
  aspect-ratio: 3/4;
  background: rgba(0, 0, 0, 0.2);
  border-radius: 18px;
  overflow: hidden;
  border: 1px solid var(--stroke);
}
#docCanvas,
#sigCanvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}
#sigCanvas {
  pointer-events: auto;
}
#placeholder {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--muted);
  font-size: 18px;
}

.footer {
  padding: 10px 16px;
  border-top: 1px solid var(--stroke);
  color: var(--muted);
  text-align: center;
}