*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg:        #0a0a0a;
  --surface:   #141414;
  --surface2:  #1e1e1e;
  --border:    #2a2a2a;
  --green:     #00e676;
  --green-glow:rgba(0,230,118,0.25);
  --red:       #ff1744;
  --red-glow:  rgba(255,23,68,0.25);
  --amber:     #ffab00;
  --text:      #c8c8c8;
  --text-dim:  #555;
  --mono:      'Share Tech Mono', monospace;
  --ui:        'Rajdhani', sans-serif;
}

html, body { height: 100%; overflow: hidden; background: var(--bg); color: var(--text); font-family: var(--ui); }

/* ── Modal ─────────────────────────────────────────────────────────────── */
.modal {
  position: fixed; inset: 0;
  background: var(--bg);
  display: flex; align-items: center; justify-content: center;
  z-index: 100;
}
.modal-box {
  display: flex; flex-direction: column; align-items: center;
  gap: 20px; width: 320px; padding: 0 20px;
}
.modal-logo {
  font-family: var(--mono); font-size: 2.2rem; color: var(--green);
  letter-spacing: 0.25em; text-shadow: 0 0 24px var(--green-glow);
}
.modal-sub {
  font-family: var(--mono); font-size: 0.65rem; color: var(--text-dim);
  letter-spacing: 0.3em;
}
.modal-box input {
  width: 100%;
  background: var(--surface); border: 1px solid var(--border); border-radius: 4px;
  color: var(--green); font-family: var(--mono); font-size: 1.2rem;
  padding: 14px 16px; text-align: center; letter-spacing: 0.2em;
  outline: none; text-transform: uppercase;
  transition: border-color 0.15s;
}
.modal-box input:focus { border-color: var(--green); box-shadow: 0 0 0 1px var(--green); }
.modal-box button {
  width: 100%; background: var(--green); border: none; border-radius: 4px;
  color: #000; font-family: var(--ui); font-size: 1.1rem; font-weight: 700;
  padding: 14px; letter-spacing: 0.2em; cursor: pointer;
  transition: opacity 0.1s;
}
.modal-box button:hover { opacity: 0.85; }

/* ── Header ────────────────────────────────────────────────────────────── */
header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 10px 20px; border-bottom: 1px solid var(--border);
  background: var(--surface); height: 48px;
}
.hdr-left { display: flex; align-items: center; gap: 14px; }
.logo { font-family: var(--mono); font-size: 1rem; color: var(--green); letter-spacing: 0.2em; }
.hdr-callsign { font-family: var(--mono); font-size: 0.8rem; color: var(--text-dim); }
.hdr-right { display: flex; align-items: center; gap: 8px; }
.status-dot {
  width: 8px; height: 8px; border-radius: 50%; background: var(--text-dim);
  transition: background 0.3s, box-shadow 0.3s;
}
.status-dot.online  { background: var(--green); box-shadow: 0 0 8px var(--green); }
.status-dot.offline { background: var(--red); }
.status-text { font-family: var(--mono); font-size: 0.75rem; letter-spacing: 0.1em; }

/* ── Layout ────────────────────────────────────────────────────────────── */
.layout { display: flex; height: calc(100vh - 48px); }

/* ── Sidebar ───────────────────────────────────────────────────────────── */
.sidebar {
  width: 170px; flex-shrink: 0;
  background: var(--surface); border-right: 1px solid var(--border);
  padding: 16px 12px; display: flex; flex-direction: column; gap: 12px;
}
.sidebar-title {
  font-family: var(--mono); font-size: 0.65rem; color: var(--text-dim);
  letter-spacing: 0.3em; padding-bottom: 8px; border-bottom: 1px solid var(--border);
}
.channel-list { display: flex; flex-direction: column; gap: 6px; }
.ch-btn {
  background: var(--surface2); border: 1px solid var(--border); border-radius: 4px;
  color: var(--text); font-family: var(--ui); font-size: 0.95rem; font-weight: 600;
  letter-spacing: 0.08em; padding: 10px 12px; cursor: pointer;
  display: flex; justify-content: space-between; align-items: center;
  transition: border-color 0.1s, color 0.1s, background 0.1s;
  text-align: left;
}
.ch-btn:hover  { border-color: var(--green); color: var(--green); }
.ch-btn.active { border-color: var(--green); color: var(--green); background: rgba(0,230,118,0.07); }
.ch-count { font-family: var(--mono); font-size: 0.7rem; color: var(--text-dim); }
.ch-btn.active .ch-count { color: var(--green); }

/* ── Radio panel ───────────────────────────────────────────────────────── */
.radio-panel {
  flex: 1;
  display: flex; flex-direction: column; align-items: center; justify-content: space-between;
  padding: 48px 24px;
}

/* Channel display */
.ch-display { text-align: center; }
.ch-label   { font-family: var(--mono); font-size: 0.65rem; color: var(--text-dim); letter-spacing: 0.35em; margin-bottom: 10px; }
.ch-name    {
  font-family: var(--mono); font-size: 3.5rem; color: var(--green);
  letter-spacing: 0.1em; text-shadow: 0 0 28px var(--green-glow);
}
.ch-units   { font-family: var(--mono); font-size: 0.7rem; color: var(--text-dim); letter-spacing: 0.2em; margin-top: 8px; }

/* TX indicator */
.tx-box {
  background: rgba(255,23,68,0.08); border: 1px solid var(--red);
  border-radius: 6px; padding: 16px 40px; text-align: center;
}
.tx-flash {
  font-family: var(--mono); font-size: 0.8rem; color: var(--red);
  letter-spacing: 0.3em; animation: blink 0.7s ease-in-out infinite;
}
@keyframes blink { 0%,100%{opacity:1} 50%{opacity:0.2} }
.tx-callsign { font-family: var(--mono); font-size: 1.6rem; color: var(--text); margin-top: 6px; letter-spacing: 0.1em; }

/* Signal meter */
.meter-wrap  { display: flex; flex-direction: column; align-items: center; gap: 8px; }
.meter-label { font-family: var(--mono); font-size: 0.65rem; color: var(--text-dim); letter-spacing: 0.3em; }
.meter-bars  { display: flex; gap: 5px; align-items: flex-end; height: 28px; }
.bar {
  width: 10px; border-radius: 2px; background: var(--border);
  transition: background 0.08s, box-shadow 0.08s;
}
.bar:nth-child(1){height:8px} .bar:nth-child(2){height:13px}
.bar:nth-child(3){height:18px} .bar:nth-child(4){height:23px} .bar:nth-child(5){height:28px}
.bar.lit      { background: var(--green); box-shadow: 0 0 5px var(--green); }
.bar.lit.peak { background: var(--amber); box-shadow: 0 0 5px var(--amber); }

/* PTT */
.ptt-wrap { display: flex; flex-direction: column; align-items: center; gap: 14px; }
.ptt-hint { font-family: var(--mono); font-size: 0.6rem; color: var(--text-dim); letter-spacing: 0.12em; text-align: center; }
.ptt-btn {
  width: 148px; height: 148px; border-radius: 50%;
  background: var(--surface2); border: 3px solid var(--border);
  color: var(--text); cursor: pointer;
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 6px;
  transition: border-color 0.1s, background 0.1s, box-shadow 0.1s;
  user-select: none; -webkit-user-select: none; touch-action: none;
}
.ptt-btn:not(:disabled):hover { border-color: var(--green); }
.ptt-btn.active {
  background: rgba(255,23,68,0.12); border-color: var(--red);
  box-shadow: 0 0 36px var(--red-glow);
}
.ptt-btn:disabled { opacity: 0.35; cursor: not-allowed; }
.ptt-icon  { font-size: 2.2rem; line-height: 1; }
.ptt-label { font-family: var(--mono); font-size: 0.85rem; letter-spacing: 0.35em; }
.ptt-status { font-family: var(--mono); font-size: 0.65rem; color: var(--text-dim); letter-spacing: 0.2em; }

/* Utility */
.hidden { display: none !important; }

/* Mobile */
@media (max-width: 500px) {
  .sidebar { width: 130px; }
  .ch-name { font-size: 2.5rem; }
  .ptt-btn { width: 130px; height: 130px; }
}