body { min-height: 100vh; }
.canvas-hint { padding: 24px; max-width: 600px; }
.canvas-hint img { width: 100%; border-radius: 10px; opacity: .5; }
.login-overlay { width: 320px; background: var(--panel); border: 1px solid var(--line); border-radius: 12px; padding: 18px; box-shadow: 0 10px 40px rgba(0,0,0,.5); }
.login-head { display: flex; align-items: center; gap: 10px; margin-bottom: 10px; }
.login-head img { width: 32px; height: 32px; border-radius: 8px; }
/* A1 compact: dead-center isolated overlay */
html.compact .login-overlay { position: fixed; left: 50%; top: 50%; transform: translate(-50%, -50%); }
/* A1 desktop: top-right fixed anchor */
html.desktop .login-overlay { position: fixed; right: 16px; top: 16px; }