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input{flex-grow:1;padding:10px;border:none;border-radius:20px;margin:0 10px}.chat-input i{color:#919191;cursor:pointer}.message-container{display:flex;margin-top:13px}.message-container.m-sent{justify-content:end}.chat-app{display:flex;margin-left:10%;margin-top:7vh;width:80%;height:90vh}.lightbox-overlay{position:fixed;inset:0;background-color:#000000e6;display:flex;align-items:center;justify-content:center;z-index:1000;cursor:pointer}.lightbox-content{position:relative;max-width:90vw;max-height:90vh;cursor:default}.lightbox-image{max-width:100%;max-height:90vh;object-fit:contain;display:block}.lightbox-close{position:absolute;top:-40px;right:0;background:none;border:none;color:#fff;font-size:24px;cursor:pointer;padding:8px;border-radius:50%;transition:background-color .2s ease}.lightbox-close:hover{background-color:#ffffff1a}.lightbox-caption{position:absolute;bottom:-40px;left:0;right:0;color:#fff;text-align:center;font-size:14px;padding:8px}@media (max-width: 768px){.lightbox-content{max-width:95vw;max-height:95vh}.lightbox-close{top:-35px;font-size:20px}.lightbox-caption{bottom:-35px;font-size:12px}}.d-f{display:flex}.d-f input{width:80%}.d-f button{width:100px;padding:.5em;background-color:#4caf50;color:#fff;border:none;cursor:pointer;margin-left:20px;margin-right:18px;height:33px}.selected-user{display:flex;align-items:center;justify-content:space-between;margin-bottom:10px}.selected-user button{width:61px;padding:.5em;background-color:#ef3d65;color:#fff;border:none;cursor:pointer}@media (max-width: 768px){.chat-app.mobile{display:flex;flex-direction:column;height:100vh}.file-details .file-name{width:120px;overflow:hidden}.chat-app.mobile .sidebar,.chat-app.mobile .chat-area-container{width:100%;height:100%}.chat-area-container{display:flex;flex-direction:column}.back-button{background-color:#f0f0f0;border:none;z-index:999;padding:10px 15px;font-size:16px;cursor:pointer;display:flex;align-items:center;gap:5px;position:absolute;bottom:14px;right:20px}.back-button:hover{background-color:#e0e0e0}.chat-area{flex-grow:1;display:flex;flex-direction:column}.chat-app.mobile,.chat-area{width:100%!important;margin-left:0%}}.chat-app.desktop .sidebar{width:30%;min-width:300px}.chat-app.desktop .chat-area{flex-grow:1}