body {
  font-family: Inter, system-ui, sans-serif;
  background: #f9fafb;
  color: #0f172a;
  margin: 0;
}

.header {
  text-align: center;
  padding: 40px 20px;
}

.subtitle {
  color: #475569;
}

.container {
  max-width: 900px;
  margin: auto;
  padding: 20px;
}

.tool {
  background: #ffffff;
  padding: 30px;
  border-radius: 20px;
  box-shadow: 0 12px 30px rgba(0,0,0,.08);
  text-align: center;
}

.tool input {
  width: 100%;
  padding: 14px;
  margin: 12px 0;
  border-radius: 12px;
  border: 1px solid #e5e7eb;
}

.tool button {
  width: 100%;
  padding: 14px;
  border-radius: 999px;
  border: none;
  background: #2563eb;
  color: #fff;
  font-size: 16px;
  cursor: pointer;
}

.qr-result {
  margin: 25px 0;
}

.download-btn {
  display: inline-block;
  padding: 12px 22px;
  background: #16a34a;
  color: #fff;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 600;
}

.tip {
  margin-top: 15px;
  font-size: 14px;
  color: #64748b;
}

.ad {
  margin: 30px 0;
}

.footer {
  text-align: center;
  padding: 20px;
  color: #64748b;
}
.mode-select {
  display: flex;
  gap: 10px;
  margin-bottom: 15px;
}

.mode {
  flex: 1;
  padding: 10px;
  border-radius: 999px;
  border: 1px solid #e5e7eb;
  background: #f1f5f9;
  cursor: pointer;
  font-weight: 600;
}

.mode.active {
  background: #2563eb;
  color: #fff;
}

.mode-box input,
.mode-box select {
  width: 100%;
  padding: 12px;
  margin-bottom: 10px;
  border-radius: 10px;
  border: 1px solid #e5e7eb;
}

.hidden {
  display: none;
}

.color-picker {
  margin: 15px 0;
  text-align: left;
}