*{box-sizing:border-box;margin:0;padding:0;font-family:system-ui, sans-serif}
.login-body{display:flex;justify-content:center;align-items:center;height:100vh;background:#0f172a}
.login-box{background:#fff;padding:30px;border-radius:10px;width:90%;max-width:380px}
.login-box input{width:100%;padding:12px;margin:8px 0;border:1px solid #ccc;border-radius:6px}
.login-box button{width:100%;padding:12px;background:#2563eb;color:#fff;border:none;border-radius:6px;cursor:pointer}
.error{color:red;margin-bottom:10px}
.app{display:flex;height:100vh}
.sidebar{width:260px;background:#020617;color:#fff;display:flex;flex-direction:column}
.sidebar-header{padding:15px}
.sidebar-header button{width:100%;padding:10px;background:#2563eb;color:#fff;border:none;border-radius:6px;cursor:pointer}
.history-list{flex:1;overflow-y:auto;padding:10px}
.history-item{padding:10px;background:#1e293b;margin-bottom:6px;border-radius:6px;cursor:pointer;font-size:14px;display:flex;justify-content:space-between}
.sidebar-footer{padding:10px;border-top:1px solid #333;display:flex;justify-content:space-between}
.sidebar-footer a{color:#f87171;text-decoration:none}
.main{flex:1;display:flex;flex-direction:column;background:#f1f5f9}
.chat-header{padding:12px;background:#fff;border-bottom:1px solid #ddd;display:flex;gap:10px;align-items:center}
.chat-box{flex:1;overflow-y:auto;padding:20px;display:flex;flex-direction:column;gap:16px}
.msg{max-width:85%;padding:14px 16px;border-radius:10px;line-height:1.6;white-space:pre-wrap;word-wrap:break-word}
.msg.user{align-self:flex-end;background:#2563eb;color:#fff}
.msg.assistant{align-self:flex-start;background:#fff;border:1px solid #e2e8f0}
.msg pre{background:#1e293b;color:#e2e8f0;padding:12px;border-radius:6px;overflow-x:auto;position:relative;margin:10px 0}
.code-actions{position:absolute;top:6px;right:6px;display:flex;gap:6px}
.code-actions button{font-size:12px;padding:4px 8px;border:none;border-radius:4px;cursor:pointer;background:#334155;color:#fff}
.input-area{background:#fff;padding:12px;border-top:1px solid #ddd}
.input-row{display:flex;gap:8px;align-items:flex-end}
.input-row textarea{flex:1;padding:10px;border:1px solid #ccc;border-radius:6px;resize:none;max-height:120px}
.input-row button, .attach-btn{padding:10px 16px;background:#2563eb;color:#fff;border:none;border-radius:6px;cursor:pointer;font-size:14px}
.file-preview{font-size:13px;color:#334155;margin-bottom:6px}
.menu-btn{display:none}
@media(max-width:768px){
.sidebar{position:fixed;left:-260px;top:0;height:100%;z-index:10;transition:0.3s}
.sidebar.open{left:0}
.menu-btn{display:block}
.msg{max-width:95%}
}
.overlay{position:fixed; inset:0; background:rgba(0,0,0,0.45); display:none; z-index:9;}
.overlay.show{display:block;}
.sidebar{transition:0.25s; z-index:10;}
.sidebar.open{left:0 !important;}
.close-btn{display:none; background:#1e293b; color:#fff; border:none; padding:6px 10px; border-radius:6px; cursor:pointer;}
.history-item{display:flex; justify-content:space-between; gap:6px; align-items:center;}
.hist-title{flex:1; cursor:pointer; white-space:nowrap; overflow:hidden; text-overflow:ellipsis;}
.del{color:#f87171; cursor:pointer; font-size:12px;}
.new-chat-btn{width:100%; margin-top:10px; padding:10px; background:#2563eb; color:#fff; border:none; border-radius:6px; cursor:pointer;}
.welcome{text-align:center; padding:40px 20px; color:#64748b;}
@media(max-width:768px){
  .sidebar{position:fixed; left:-270px; top:0; height:100%;}
  .close-btn{display:block;}
  .menu-btn{display:block !important;}
}