/* 基础样式与现代UI设计 */
:root {
  --bg: #f7f8fa;
  --text: #1f2937;
  --muted: #6b7280;
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --border: #e5e7eb;
  --card: #ffffff;
}
* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Fira Sans", "Droid Sans", "Helvetica Neue", Arial, "Noto Sans SC", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: var(--bg);
}

.page-header {
  background: linear-gradient(135deg, #0ea5e9 0%, #2563eb 100%);
  color: #fff;
  padding: 40px 20px 24px;
  text-align: center;
  box-shadow: 0 2px 8px rgba(0,0,0,0.06);
}
.page-header h1 { margin: 0; font-size: 28px; letter-spacing: 1px; }
.page-header .subtitle { margin: 8px 0 0; font-size: 16px; opacity: 0.9; }

.container { max-width: 960px; margin: 24px auto; padding: 0 16px; }
.form { background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 20px; box-shadow: 0 2px 12px rgba(0,0,0,0.04); }

.form-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.form-item { display: flex; flex-direction: column; gap: 8px; }
.form-item span { font-size: 14px; color: var(--muted); }
.form-item input, .form-item textarea, .form-item select {
  width: 100%;
  padding: 10px 12px;
  font-size: 14px;
  border: 1px solid var(--border);
  border-radius: 8px;
  outline: none;
  background: #fff;
}
.form-item input:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(37,99,235,0.15); }

.actions { display: flex; gap: 12px; margin-top: 16px; }
.btn {
  appearance: none;
  border: 1px solid var(--border);
  background: #fff;
  color: var(--text);
  border-radius: 8px;
  padding: 10px 16px;
  font-size: 14px;
  cursor: pointer;
}
.btn:hover { background: #f3f4f6; }
.btn.primary { background: var(--primary); color: #fff; border-color: var(--primary); }
.btn.primary:hover { background: var(--primary-hover); }
.btn.disabled { pointer-events: none; opacity: 0.5; }

.result { margin-top: 24px; background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 20px; box-shadow: 0 2px 12px rgba(0,0,0,0.04); }
.result h2 { margin: 0 0 12px; font-size: 18px; }
.preview {
  background: #0b1021;
  color: #e5e7eb;
  padding: 12px;
  border-radius: 8px;
  font-size: 13px;
  max-height: 240px;
  overflow: auto;
}

.qrcode { display: grid; place-items: center; min-height: 180px; }
.qr-actions { display: flex; gap: 12px; margin-top: 12px; }

.page-footer { text-align: center; color: var(--muted); font-size: 12px; padding: 24px 0 40px; }

/* 响应式 */
@media (max-width: 640px) {
  .form-grid { grid-template-columns: 1fr; }
}


/* 配置区域样式 */
.config {
  margin-top: 16px;
  padding: 12px;
  border: 1px solid #e5e5e5;
  border-radius: 8px;
  background: #fafafa;
}
.config h2 {
  font-size: 18px;
  margin: 0 0 8px 0;
}
.config .tip {
  color: #666;
  font-size: 13px;
  margin: 4px 0 10px 0;
}
.config-row {
  display: flex;
  gap: 8px;
  align-items: center;
}
.config-row input[type="url"] {
  flex: 1;
  height: 36px;
  padding: 6px 10px;
  border: 1px solid #ccc;
  border-radius: 6px;
}
.config-row .btn {
  height: 36px;
}

/* 扫码查看（viewer-only）模式：仅显示“文本预览”区域 */
body.viewer-only .page-header,
body.viewer-only .form,
body.viewer-only .actions,
body.viewer-only .config,
body.viewer-only .qrcode,
body.viewer-only .qr-actions,
body.viewer-only #modeTip,
body.viewer-only .page-footer {
  display: none !important;
}
/* 隐藏“生成的二维码”标题（位于结果区的第二个 h2） */
body.viewer-only .result h2:last-of-type {
  display: none !important;
}
/* 预览区在查看模式下更高、更舒适 */
body.viewer-only .preview {
  max-height: none;
  min-height: 50vh;
}