:root {
    --bg-color: #2c2f33; --panel-bg: #36393f; --header-bg: #23272a;
    --accent-color: #7289da; --text-color: #ffffff; --msg-bg: #40444b;
}
* { box-sizing: border-box; margin: 0; padding: 0; font-family: Arial, sans-serif; }
body { background: var(--bg-color); color: var(--text-color); height: 100vh; display: flex; flex-direction: column; }
.chat-header { background: var(--header-bg); padding: 15px 20px; display: flex; justify-content: space-between; align-items: center; border-bottom: 2px solid var(--accent-color); }
.chat-header h1 { font-size: 20px; }
.lang-switch a { color: var(--accent-color); text-decoration: none; font-weight: bold; }
.chat-wrapper { display: flex; flex: 1; overflow: hidden; }
.chat-sidebar { width: 250px; background: var(--bg-color); border-left: 1px solid var(--header-bg); padding: 15px; }
.chat-sidebar h3 { font-size: 14px; color: #99aab5; text-transform: uppercase; margin-bottom: 10px; }
.user-list { list-style: none; }
.user-list li { color: var(--accent-color); padding: 5px 0; }
.chat-main { flex: 1; display: flex; flex-direction: column; background: var(--panel-bg); }
.messages { flex: 1; padding: 20px; overflow-y: auto; display: flex; flex-direction: column; gap: 10px; }
.msg { background: var(--msg-bg); padding: 10px; border-radius: 8px; max-width: 80%; }
.msg .author { color: var(--accent-color); font-weight: bold; margin-right: 10px; }
.msg .time { font-size: 11px; color: #99aab5; float: right; margin-left: 10px; }
.input-area { padding: 15px; background: var(--msg-bg); display: flex; gap: 10px; }
.input-area input { flex: 1; padding: 12px; border: none; border-radius: 5px; background: var(--bg-color); color: var(--text-color); outline: none; }
.input-area button { padding: 12px 25px; border: none; border-radius: 5px; background: var(--accent-color); color: #fff; cursor: pointer; font-weight: bold; }
.system-msg { text-align: center; color: #99aab5; font-size: 13px; margin: 10px 0; font-style: italic; }