:root {
	--bg: #0e1117;
	--panel: #151a23;
	--panel-soft: #1c2230;
	--text: #e5e9f0;
	--muted: #9ba6b6;
	--line: #2a3447;
	--accent: #31d0aa;
}

* {
	box-sizing: border-box;
}

body {
	margin: 0;
	min-height: 100vh;
	padding: 1.25rem;
	font-family: "Segoe UI", Tahoma, sans-serif;
	color: var(--text);
	background: radial-gradient(circle at top right, #1a2a42 0%, var(--bg) 45%);
}

.chat-shell {
	max-width: 1100px;
	margin: 0 auto;
	border: 1px solid var(--line);
	border-radius: 12px;
	overflow: hidden;
	display: grid;
	grid-template-columns: 220px 1fr 220px;
	min-height: 75vh;
	background: var(--panel);
}

.panel {
	padding: 1rem;
}

.panel-rooms,
.panel-members {
	background: var(--panel-soft);
}

.panel h2 {
	margin: 0 0 0.8rem;
	font-size: 0.9rem;
	letter-spacing: 0.08em;
	color: var(--muted);
}

.panel ul {
	list-style: none;
	padding: 0;
	margin: 0;
	display: grid;
	gap: 0.45rem;
}

.panel-rooms a {
	display: block;
	text-decoration: none;
	color: var(--text);
	padding: 0.45rem 0.55rem;
	border: 1px solid transparent;
	border-radius: 8px;
}

.panel-rooms a:hover,
.panel-rooms a[aria-current="true"] {
	border-color: var(--line);
	background: #111622;
}

.panel-chat {
	padding: 0;
	display: grid;
	grid-template-rows: auto 1fr auto;
	border-left: 1px solid var(--line);
	border-right: 1px solid var(--line);
}

.chat-header {
	padding: 1rem;
	border-bottom: 1px solid var(--line);
	font-weight: 600;
}

.messages {
	padding: 1rem;
	display: grid;
	align-content: start;
	gap: 1rem;
}

.message {
	max-width: 70%;
}

.author {
	margin: 0 0 0.2rem;
	font-weight: 600;
	color: #b7c6db;
}

.content {
	margin: 0;
	color: var(--text);
}

.composer {
	display: grid;
	grid-template-columns: 1fr auto;
	gap: 0.6rem;
	padding: 0.85rem;
	border-top: 1px solid var(--line);
}

.composer input {
	width: 100%;
	border: 1px solid var(--line);
	border-radius: 8px;
	background: #0f141d;
	color: var(--text);
	padding: 0.65rem 0.75rem;
}

.composer input::placeholder {
	color: var(--muted);
}

.composer button {
	border: 0;
	border-radius: 8px;
	background: var(--accent);
	color: #052b23;
	font-weight: 700;
	width: 44px;
	cursor: pointer;
}

.composer button:hover {
	filter: brightness(1.06);
}

.visually-hidden {
	position: absolute;
	width: 1px;
	height: 1px;
	padding: 0;
	margin: -1px;
	overflow: hidden;
	clip: rect(0, 0, 0, 0);
	white-space: nowrap;
	border: 0;
}

@media (max-width: 900px) {
	.chat-shell {
		grid-template-columns: 1fr;
		min-height: auto;
	}

	.panel-chat {
		border: 0;
		border-top: 1px solid var(--line);
		border-bottom: 1px solid var(--line);
		min-height: 55vh;
	}
}