開始 <script> (function(){ const KEY = "experiment_client_uuid"; function genUUID(){ if (window.crypto && crypto.randomUUID) return crypto.randomUUID(); // fallback const s4 = () => Math.floor((1+Math.random())*0x10000).toString(16).substring(1); return `${s4()}${s4()}-${s4()}-${s4()}-${s4()}-${s4()}${s4()}${s4()}`; } let v = null; try { v = localStorage.getItem(KEY); } catch(e) {} if(!v){ v = genUUID(); try { localStorage.setItem(KEY, v); } catch(e) {} } const el = document.getElementById("client_uuid"); if(el) el.value = v || ""; })(); </script>