* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --background: 0 0% 100%;
  --foreground: 222.2 84% 4.9%;
  --card: 0 0% 100%;
  --card-foreground: 222.2 84% 4.9%;
  --popover: 0 0% 100%;
  --popover-foreground: 222.2 84% 4.9%;
  --primary: 222.2 47.4% 11.2%;
  --primary-foreground: 210 40% 98%;
  --secondary: 210 40% 96.1%;
  --secondary-foreground: 222.2 47.4% 11.2%;
  --muted: 210 40% 96.1%;
  --muted-foreground: 215.4 16.3% 46.9%;
  --accent: 210 40% 96.1%;
  --accent-foreground: 222.2 47.4% 11.2%;
  --destructive: 0 84.2% 60.2%;
  --destructive-foreground: 210 40% 98%;
  --border: 214.3 31.8% 91.4%;
  --input: 214.3 31.8% 91.4%;
  --ring: 222.2 84% 4.9%;
  --radius: 0.5rem;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  background: hsl(var(--background));
  color: hsl(var(--foreground));
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 20px;
}

.container {
  background: hsl(var(--card));
  border: 1px solid hsl(var(--border));
  border-radius: var(--radius);
  padding: 32px;
  box-shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
  max-width: 750px;
  width: 100%;
}

h1 {
  text-align: center;
  color: hsl(var(--foreground));
  margin-bottom: 24px;
  font-size: 24px;
  font-weight: 600;
  letter-spacing: -0.025em;
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  margin-bottom: 8px;
  font-size: 14px;
  font-weight: 500;
  color: hsl(var(--foreground));
}

.required {
  color: hsl(var(--destructive));
}

.input {
  width: 100%;
  height: 40px;
  padding: 0 12px;
  border: 1px solid hsl(var(--border));
  border-radius: calc(var(--radius) - 2px);
  font-size: 14px;
  background: hsl(var(--background));
  color: hsl(var(--foreground));
  transition: border-color 0.15s ease;
}

.input:focus {
  outline: none;
  border-color: hsl(var(--ring));
  box-shadow: 0 0 0 3px hsl(var(--ring) / 0.1);
}

.input::placeholder {
  color: hsl(var(--muted-foreground));
}

.signature-box {
  border: 2px solid hsl(var(--border));
  border-radius: calc(var(--radius) - 2px);
  margin-bottom: 16px;
  overflow: hidden;
  background: hsl(var(--background));
  display: flex;
  justify-content: center;
  align-items: center;
}

#signatureCanvas {
  display: block;
  cursor: crosshair;
  touch-action: none;
  width: 618px;
  height: 260px;
}

.controls {
  display: flex;
  gap: 8px;
  flex-direction: column;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  white-space: nowrap;
  border-radius: calc(var(--radius) - 2px);
  font-size: 14px;
  font-weight: 500;
  transition: all 0.15s ease;
  cursor: pointer;
  height: 40px;
  padding: 0 16px;
  border: none;
  outline: none;
}

.btn:focus-visible {
  outline: 2px solid hsl(var(--ring));
  outline-offset: 2px;
}

.btn:disabled {
  pointer-events: none;
  opacity: 0.5;
}

.btn-primary {
  background: hsl(var(--primary));
  color: hsl(var(--primary-foreground));
}

.btn-primary:hover {
  background: hsl(var(--primary) / 0.9);
}

.btn-secondary {
  background: hsl(var(--secondary));
  color: hsl(var(--secondary-foreground));
  border: 1px solid hsl(var(--border));
}

.btn-secondary:hover {
  background: hsl(var(--accent));
}

.status-message {
  margin-top: 16px;
  padding: 12px;
  border-radius: calc(var(--radius) - 2px);
  font-size: 14px;
  text-align: center;
  display: none;
}

.status-message.success {
  display: block;
  background: hsl(142.1 76.2% 36.3% / 0.1);
  color: hsl(142.1 76.2% 36.3%);
  border: 1px solid hsl(142.1 76.2% 36.3% / 0.3);
}

.status-message.error {
  display: block;
  background: hsl(var(--destructive) / 0.1);
  color: hsl(var(--destructive));
  border: 1px solid hsl(var(--destructive) / 0.3);
}

.status-message.loading {
  display: block;
  background: hsl(var(--muted));
  color: hsl(var(--muted-foreground));
  border: 1px solid hsl(var(--border));
}

@media (max-width: 768px) {
  .container {
    padding: 24px;
  }
  
  h1 {
    font-size: 20px;
  }
  
  #signatureCanvas {
    width: 100%;
    height: auto;
  }
}