/* ── Reset & base ─────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
    --bg-base:       #0d1117;
    --bg-raised:     #161b22;
    --bg-panel:      #1c2128;
    --bg-hover:      #21262d;
    --bg-active:     #2d333b;
    --border:        #30363d;
    --border-subtle: #21262d;

    --text-primary:  #e6edf3;
    --text-muted:    #8b949e;
    --text-dim:      #484f58;

    --accent:        #58a6ff;
    --accent-dim:    #1f6feb;
    --green:         #3fb950;
    --amber:         #d29922;
    --red:           #f85149;

    --callsign-1:    #79c0ff;
    --callsign-2:    #7ee787;
    --callsign-3:    #ffa657;
    --callsign-4:    #d2a8ff;
    --callsign-5:    #39d353;

    --font-mono:     'JetBrains Mono', 'Fira Code', 'Cascadia Code', 'Consolas', 'Menlo', monospace;
    --font-ui:       -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;

    --header-h:      48px;
    --footer-h:      40px;
    --sidebar-w:     220px;
    --radius:        6px;
    --radius-sm:     4px;
}

html, body {
    height: 100%;
    background: var(--bg-base);
    color: var(--text-primary);
    font-family: var(--font-ui);
    font-size: 14px;
    line-height: 1.5;
    overflow: hidden;          /* full-page layout; inner areas scroll */
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ── Header ───────────────────────────────────────────────────────────── */
.site-header {
    position: fixed;
    top: 0; left: 0; right: 0;
    height: var(--header-h);
    background: var(--bg-raised);
    border-bottom: 1px solid var(--border);
    z-index: 100;
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
    padding: 0 16px;
    gap: 12px;
}

.header-left {
    display: flex;
    align-items: center;
    gap: 16px;
    min-width: 0;
}

.site-title {
    font-family: var(--font-mono);
    font-size: 15px;
    font-weight: 700;
    color: var(--accent);
    white-space: nowrap;
    letter-spacing: 0.04em;
}

.header-meta {
    font-size: 12px;
    color: var(--text-muted);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-shrink: 0;
}

.stat-chip {
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--text-muted);
    background: var(--bg-panel);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    padding: 2px 8px;
    white-space: nowrap;
}

.callsign-badge {
    font-family: var(--font-mono);
    font-size: 12px;
    font-weight: 700;
    color: var(--green);
    background: rgba(63, 185, 80, 0.1);
    border: 1px solid rgba(63, 185, 80, 0.3);
    border-radius: var(--radius-sm);
    padding: 2px 10px;
    letter-spacing: 0.06em;
}

/* ── Full-page layout ─────────────────────────────────────────────────── */
.layout {
    display: flex;
    position: fixed;
    top: var(--header-h);
    bottom: var(--footer-h);
    left: 0;
    right: 0;
    overflow: hidden;
}

/* ── Sidebar ──────────────────────────────────────────────────────────── */
.sidebar {
    width: var(--sidebar-w);
    flex-shrink: 0;
    background: var(--bg-raised);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    overflow-y: auto;
    overflow-x: hidden;
}

.sidebar-section {
    padding: 12px 0;
    border-bottom: 1px solid var(--border-subtle);
}

.sidebar-heading {
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 0.1em;
    color: var(--text-dim);
    padding: 0 12px 6px;
    text-transform: uppercase;
}

/* Channel list */
.channel-list {
    list-style: none;
}

.channel-list li {
    display: block;
}

.channel-btn {
    display: flex;
    align-items: center;
    width: 100%;
    padding: 5px 12px;
    font-family: var(--font-mono);
    font-size: 13px;
    color: var(--text-muted);
    background: transparent;
    border: none;
    cursor: pointer;
    text-align: left;
    gap: 4px;
    transition: background 0.1s, color 0.1s;
}

.channel-btn:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

.channel-btn.active {
    background: var(--bg-active);
    color: var(--accent);
}

.channel-btn .ch-hash {
    color: var(--text-dim);
}

.channel-btn.active .ch-hash {
    color: var(--accent-dim);
}

.unread-dot {
    display: inline-block;
    width: 6px; height: 6px;
    background: var(--accent);
    border-radius: 50%;
    margin-left: auto;
    flex-shrink: 0;
}

/* Help panel */
.help-toggle {
    display: flex;
    align-items: center;
    gap: 6px;
    width: 100%;
    padding: 8px 12px;
    font-size: 12px;
    color: var(--text-muted);
    background: transparent;
    border: none;
    cursor: pointer;
    text-align: left;
    transition: color 0.1s;
}
.help-toggle:hover { color: var(--text-primary); }

.help-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 16px; height: 16px;
    border: 1px solid var(--text-dim);
    border-radius: 50%;
    font-size: 10px;
    color: var(--text-dim);
    flex-shrink: 0;
}

.help-panel {
    padding: 8px 12px 4px;
}

.help-intro {
    font-size: 11px;
    color: var(--text-muted);
    margin-bottom: 8px;
}
.help-intro strong { color: var(--accent); }

.cmd-list {
    font-family: var(--font-mono);
    font-size: 11px;
}
.cmd-list dt {
    color: var(--amber);
    margin-top: 6px;
}
.cmd-list dd {
    color: var(--text-muted);
    margin-left: 8px;
}

/* ── Main content area ────────────────────────────────────────────────── */
.content {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: var(--bg-base);
}

.channel-pane-container {
    flex: 1;
    overflow: hidden;
    position: relative;
}

/* ── Channel pane ─────────────────────────────────────────────────────── */
.channel-pane {
    display: none;
    flex-direction: row;
    height: 100%;
    overflow: hidden;
}

.channel-pane.visible {
    display: flex;
}

/* Message feed */
.msg-feed {
    flex: 1;
    min-width: 0;
    overflow-y: auto;
    padding: 0;
    scroll-behavior: smooth;
}

/* Users panel */
.users-panel {
    width: 140px;
    flex-shrink: 0;
    border-left: 1px solid var(--border);
    background: var(--bg-raised);
    overflow-y: auto;
    padding: 10px 0;
}

.users-heading {
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--text-dim);
    padding: 0 10px 8px;
}

.user-entry {
    display: block;
    font-family: var(--font-mono);
    font-size: 12px;
    padding: 3px 10px;
    color: var(--text-muted);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* ── Message row ──────────────────────────────────────────────────────── */
.msg-row {
    display: flex;
    align-items: baseline;
    padding: 3px 12px;
    border-bottom: 1px solid var(--border-subtle);
    font-family: var(--font-mono);
    font-size: 12.5px;
    line-height: 1.55;
    gap: 0;
    transition: background 0.05s;
}
.msg-row:hover { background: var(--bg-raised); }

.msg-time {
    color: var(--text-dim);
    font-size: 11px;
    width: 150px;
    flex-shrink: 0;
    white-space: nowrap;
    padding-right: 8px;
    border-right: 1px solid var(--border-subtle);
}

.msg-call {
    width: 100px;
    flex-shrink: 0;
    font-weight: 600;
    font-size: 12px;
    padding: 0 8px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    border-right: 1px solid var(--border-subtle);
}

.msg-text {
    flex: 1;
    min-width: 0;
    padding-left: 10px;
    color: var(--text-primary);
    word-break: break-word;
    white-space: pre-wrap;
}

/* Empty state */
.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    color: var(--text-dim);
    font-family: var(--font-mono);
    font-size: 13px;
    gap: 8px;
}
.empty-state .empty-icon { font-size: 32px; opacity: 0.4; }

/* No channels state */
.no-channels {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    color: var(--text-muted);
    font-family: var(--font-mono);
    font-size: 13px;
    gap: 12px;
    text-align: center;
    padding: 24px;
}
.no-channels-title { color: var(--text-primary); font-size: 15px; }

/* ── Footer ───────────────────────────────────────────────────────────── */
.site-footer {
    position: fixed;
    bottom: 0; left: 0; right: 0;
    height: var(--footer-h);
    background: var(--bg-raised);
    border-top: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 16px;
    font-size: 11px;
    color: var(--text-dim);
    z-index: 100;
}

.footer-note { color: var(--text-dim); }

/* ── Scrollbar styling (Webkit) ───────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-dim); }

/* ── Responsive ───────────────────────────────────────────────────────── */
@media (max-width: 600px) {
    :root { --sidebar-w: 0px; }
    .sidebar { display: none; }
    .msg-call { width: 70px; }
    .msg-time  { width: 110px; font-size: 10px; }
    .users-panel { width: 90px; }
}