docs: fix terminal bg gradient bug, simplify nav logo

- Remove broken linear-gradient from .terminal-body that caused a white
  artifact at the top of every terminal block
- Replace animated SVG logo in nav with a clean static "do" wordmark icon;
  the blinking cursor animation was distracting and cluttered the nav bar

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: franckferman

docs/index.html

@@ -345,7 +345,6 @@
       font-size: .8rem;
       line-height: 1.8;
       -webkit-overflow-scrolling: touch;
-      background: linear-gradient(180deg, rgba(255,255,255,.012) 0%, transparent 60px);
     }
 
     .p  { color: #2dd4bf; user-select: none; }  /* teal prompt $ */
@@ -743,23 +742,9 @@
 <!-- ================================================================= NAV -->
 <nav>
   <a href="#top" class="nav-logo">
-    <svg width="28" height="28" viewBox="0 0 28 28" fill="none" xmlns="http://www.w3.org/2000/svg">
-      <rect width="28" height="28" rx="7" fill="#0052cc"/>
-      <rect width="28" height="28" rx="7" fill="url(#logo-g)" opacity=".6"/>
-      <defs>
-        <linearGradient id="logo-g" x1="0" y1="0" x2="28" y2="28" gradientUnits="userSpaceOnUse">
-          <stop offset="0%" stop-color="#4d9fff" stop-opacity=".5"/>
-          <stop offset="100%" stop-color="#003999" stop-opacity=".3"/>
-        </linearGradient>
-      </defs>
-      <!-- $ prompt -->
-      <text x="5" y="17" font-family="monospace" font-size="11" font-weight="700" fill="rgba(255,255,255,.9)">$</text>
-      <!-- cursor underscore -->
-      <rect x="14" y="17.5" width="8" height="2" rx="1" fill="rgba(255,255,255,.75)"/>
-      <!-- blink animation on cursor -->
-      <rect x="14" y="17.5" width="8" height="2" rx="1" fill="white" opacity=".4">
-        <animate attributeName="opacity" values="0.4;0;0.4" dur="1.2s" repeatCount="indefinite"/>
-      </rect>
+    <svg width="26" height="26" viewBox="0 0 26 26" fill="none" xmlns="http://www.w3.org/2000/svg">
+      <rect width="26" height="26" rx="6" fill="#0052cc"/>
+      <text x="5" y="18" font-family="monospace" font-size="13" font-weight="700" fill="white">do</text>
     </svg>
     <span><span class="logo-do">do</span><span class="logo-dash">-</span><span class="logo-mgr">manager</span></span>
   </a>