docs: compact user guide pdf layout

docs/user-guide.html

@@ -243,9 +243,96 @@
     }
 
     @media print {
+      @page {
+        size: A4;
+        margin: 8mm;
+      }
       body { background: #fff; }
       .shell { max-width: none; padding: 0; }
-      .hero, .section, figure { box-shadow: none; break-inside: avoid; }
+      .hero, .section {
+        box-shadow: none;
+        border: 0;
+        border-radius: 0;
+        padding: 0;
+        margin-top: 8px;
+        background: transparent;
+      }
+      .hero {
+        padding-bottom: 8px;
+        border-bottom: 1px solid var(--line);
+      }
+      h1 { font-size: 23px; }
+      h2 {
+        font-size: 16px;
+        margin: 14px 0 6px;
+        padding-bottom: 5px;
+      }
+      h3 {
+        font-size: 13px;
+        margin: 9px 0 4px;
+      }
+      p, li, td, th {
+        font-size: 10.5px;
+        line-height: 1.38;
+      }
+      .meta { margin-top: 8px; }
+      .grid {
+        gap: 8px;
+        margin: 10px 0 0;
+      }
+      .card {
+        border-radius: 9px;
+        padding: 9px 10px;
+        font-size: 10.5px;
+        line-height: 1.38;
+      }
+      .card strong {
+        font-size: 12px;
+        margin-bottom: 2px;
+      }
+      .toc {
+        gap: 2px 14px;
+        margin-top: 4px;
+      }
+      .notice {
+        padding: 8px 10px;
+        margin: 8px 0;
+        border-radius: 9px;
+        font-size: 10.5px;
+        line-height: 1.38;
+      }
+      .steps li {
+        padding-left: 30px;
+        margin: 8px 0;
+      }
+      .steps li::before {
+        width: 20px;
+        height: 20px;
+        line-height: 20px;
+        font-size: 11px;
+      }
+      table { margin: 9px 0; border-radius: 8px; }
+      th, td { padding: 6px 8px; }
+      figure {
+        box-shadow: none;
+        break-inside: avoid;
+        width: max-content;
+        max-width: 100%;
+        margin: 5px auto;
+        border-radius: 8px;
+      }
+      figure img {
+        width: auto;
+        max-width: 100%;
+        max-height: 62mm;
+        margin: 0 auto;
+        object-fit: contain;
+        background: #fff;
+      }
+      figcaption {
+        padding: 5px 8px;
+        font-size: 10px;
+      }
       a { color: #111827; }
     }
   </style>