.app-container{display:flex;max-height:70vh;background:#f6f7fb;font-family:Arial,sans-serif}.sidebar{width:25%;background:#111b21;border-right:1px solid #202c33;display:flex;flex-direction:column}.sidebar-header{padding:5px;background:#111b21;color:#fff;font-size:1.5em;font-weight:700;text-align:center}.chat-list-container{flex:1;overflow-y:auto;min-height:200px}.sidebar ul{list-style:none;padding:0;margin:0;flex:1;overflow-y:auto;min-height:50vh}.sidebar li{padding:10px;border-bottom:1px solid #f0f0f0;cursor:pointer;transition:background-color .2s ease}.sidebar li:hover{background:#f9f9f9}.sidebar li.active{background:#e0f7fa}.avatar,.chat-item{display:flex;align-items:center}.avatar{width:40px;height:40px;background:#3455eb;color:#fff;justify-content:center;border-radius:50%;margin-right:10px;font-size:1.2em}.chat-details{flex:1}.chat-name{font-weight:700;color:#fff}.last-message{font-size:.9em;color:#fff}.chat-window{flex:1;display:flex;flex-direction:column;background:#0b141a;position:relative}.messages-container{flex:1;overflow-y:auto;padding:10px;max-height:54vh}.chat-header{padding:10px;background:#202c33;color:#fff;font-size:1.3em}.messages{display:flex;flex-direction:column;max-height:100%}.message{background:#e0f7fa;padding:10px 15px;margin:5px 0;border-radius:10px;max-width:60%;position:relative}.message-sender{background:#d1f3d1;align-self:flex-end;text-align:right}.message-content{display:flex;flex-direction:column}.message-time{font-size:.8em;color:grey;margin-top:5px;align-self:flex-end}.message-input{display:flex;align-items:center;padding:10px;background:#202c33;border-top:1px solid #202c33;position:absolute;bottom:0;left:0;width:100%}.message-input input{flex:1;padding:10px;border:1px solid #2a3942;background:#2a3942;border-radius:20px;outline:none;color:#d1d7db}.message-input button{margin-left:10px;background:#00bfa5;border:none;border-radius:50%;padding:10px;display:flex;align-items:center;justify-content:center;cursor:pointer}.message-input button svg{fill:#fff}.message-input button:hover{background:#00796b}.no-chat{flex:1;display:flex;align-items:center;justify-content:center;color:grey;font-size:1.2em}.sidebar li.active{background:#2a3942}.message-name{font-weight:700;font-size:.9em;margin-bottom:5px;display:block}.search-chat{padding:15px;border-bottom:1px solid #ccc}#search-chat-input{width:100%;padding:10px;font-size:16px;border:none;border-radius:5px;box-shadow:0 0 10px rgba(0,0,0,.1)}#chat-list{list-style:none;padding:0;margin:0}#chat-list li{padding:10px;border-bottom:1px solid #ccc}#chat-list li:hover{background-color:#f0f0f0}