frontend/style.css

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

:root {
  --bg: #05070d;
  --panel: rgba(10, 14, 24, 0.76);
  --panel-strong: rgba(13, 18, 30, 0.94);
  --panel-soft: rgba(255, 255, 255, 0.03);
  --border: rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.14);
  --text: #e5eefb;
  --text-2: #a9b7cc;
  --text-3: #6f7d92;
  --accent: #f5f7fb;
  --accent-2: #64b5ff;
  --good: #16a34a;
  --warn: #f59e0b;
  --danger: #ff5e7b;
  --shadow: 0 22px 60px rgba(0, 0, 0, 0.45);
  --shadow-soft: 0 10px 26px rgba(0, 0, 0, 0.32);
  --radius-xl: 28px;
  --radius-lg: 20px;
  --radius-md: 14px;
  --radius-sm: 10px;
  --sidebar-w: 304px;
  --max-chat: 860px;
}

html,
body {
  height: 100%;
  margin: 0;
  background:
    radial-gradient(circle at top left, rgba(100, 181, 255, 0.14), transparent 20%),
    radial-gradient(circle at 75% 25%, rgba(133, 95, 255, 0.12), transparent 18%),
    radial-gradient(circle at bottom right, rgba(22, 163, 74, 0.08), transparent 22%),
    var(--bg);
  color: var(--text);
  font-family: 'Hind Siliguri', 'Syne', sans-serif;
  overflow: hidden;
}

body {
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

button,
input,
select {
  font: inherit;
}

button {
  appearance: none;
}

/* ── Layout ───────────────────────────────────────────────────────────────── */
.app {
  position: fixed;
  inset: 0;
  display: flex;
  opacity: 1;
  pointer-events: auto;
}

.sidebar {
  width: var(--sidebar-w);
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  background: rgba(8, 12, 20, 0.82);
  backdrop-filter: blur(20px);
  border-right: 1px solid var(--border);
  box-shadow: inset -1px 0 0 rgba(255, 255, 255, 0.03);
  overflow-y: auto;
}

.sidebar.collapsed {
  width: 0;
  overflow: hidden;
}

.sidebar-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 16px 14px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: 'Syne', sans-serif;
  font-weight: 700;
  font-size: 14px;
  letter-spacing: 0.02em;
}

.sidebar-toggle,
.brain-btn,
.clear-btn,
.mobile-menu-btn,
.stop-btn,
#send-btn,
.mic-btn,
.setting-select,
#text-input {
  border: 1px solid var(--border);
}

.sidebar-toggle {
  width: 34px;
  height: 34px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.04);
  color: var(--text-2);
  display: grid;
  place-items: center;
  cursor: pointer;
  transition: transform 0.15s ease, border-color 0.15s ease;
}

.sidebar-toggle:hover {
  border-color: var(--border-strong);
  transform: translateY(-1px);
}

.sidebar-divider {
  height: 1px;
  margin: 4px 16px;
  background: var(--border);
}

.dash-section {
  padding: 16px;
}

.dash-title {
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-3);
  margin-bottom: 12px;
}

.metric-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.metric-card {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 12px 10px;
  box-shadow: var(--shadow-soft);
  text-align: center;
}

.metric-val {
  font-family: 'JetBrains Mono', monospace;
  font-size: 18px;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 4px;
}

.metric-label,
.queue-label,
.status-label {
  color: var(--text-3);
  font-size: 11px;
}

.setting-row {
  margin-bottom: 14px;
}

.setting-row label {
  display: block;
  font-size: 11px;
  color: var(--text-2);
  margin-bottom: 8px;
}

.slider-wrap {
  display: flex;
  align-items: center;
  gap: 10px;
}

.slider-wrap input[type='range'] {
  flex: 1;
  accent-color: var(--accent-2);
}

.slider-wrap span {
  min-width: 64px;
  text-align: right;
  font-size: 11px;
  color: var(--text-2);
  font-family: 'JetBrains Mono', monospace;
}

.setting-select {
  width: 100%;
  padding: 11px 12px;
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
}

.setting-select:focus,
#text-input:focus {
  outline: none;
  border-color: rgba(37, 99, 235, 0.4);
  box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.08);
}

.queue-vis {
  display: flex;
  align-items: flex-end;
  gap: 4px;
  height: 48px;
  margin-bottom: 8px;
}

.queue-bar {
  flex: 1;
  min-height: 4px;
  border-radius: 999px;
  background: linear-gradient(180deg, rgba(37, 99, 235, 0.85), rgba(15, 23, 42, 0.55));
  opacity: 0.2;
  transition: height 0.14s ease, opacity 0.14s ease;
}

.queue-bar.active {
  opacity: 0.95;
}

/* ── Main column ──────────────────────────────────────────────────────────── */
.main {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 18px;
  border-bottom: 1px solid var(--border);
  background: rgba(8, 12, 20, 0.72);
  backdrop-filter: blur(18px);
  flex-shrink: 0;
}

.topbar-left,
.topbar-right {
  display: flex;
  align-items: center;
  gap: 10px;
}

.topbar-center {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  font-family: 'Syne', sans-serif;
  font-weight: 700;
  font-size: 14px;
  color: var(--text);
  letter-spacing: 0.01em;
}

.topbar-title {
  opacity: 0.92;
}

.topbar-state {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.04);
  box-shadow: var(--shadow-soft);
}

.state-dot {
  width: 8px;
  height: 8px;
  border-radius: 999px;
  background: var(--good);
  box-shadow: 0 0 0 4px rgba(22, 163, 74, 0.12);
}

.state-dot.listening {
  background: var(--accent-2);
  box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.12);
}

.state-dot.recording {
  background: var(--danger);
  box-shadow: 0 0 0 4px rgba(239, 68, 68, 0.12);
}

.state-dot.processing {
  background: var(--warn);
  box-shadow: 0 0 0 4px rgba(217, 119, 6, 0.12);
}

.state-dot.speaking {
  background: var(--accent);
  box-shadow: 0 0 0 4px rgba(15, 23, 42, 0.08);
}

#state-label {
  font-size: 12px;
  color: var(--text-2);
}

.mobile-menu-btn,
.clear-btn,
.brain-btn {
  height: 38px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  cursor: pointer;
  padding: 0 14px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: transform 0.15s ease, border-color 0.15s ease, background 0.15s ease;
}

.brain-btn {
  width: 40px;
  padding: 0;
  display: grid;
  place-items: center;
}

.brain-btn.active {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.brain-btn svg {
  width: 20px;
  height: 20px;
  fill: currentColor;
}

.mobile-menu-btn:hover,
.clear-btn:hover,
.brain-btn:hover,
.sidebar-toggle:hover,
.stop-btn:hover,
#send-btn:hover,
.mic-btn:hover {
  transform: translateY(-1px);
}

.clear-btn {
  font-size: 12px;
  color: var(--text-2);
}

.voice-caption {
  width: min(var(--max-chat), calc(100% - 32px));
  margin: 14px auto 0;
  min-height: 24px;
  color: var(--text-2);
  font-size: 12px;
  line-height: 1.5;
  letter-spacing: 0.01em;
  padding: 0 4px;
  transition: opacity 0.2s ease;
}

#chat-box {
  width: min(var(--max-chat), calc(100% - 32px));
  margin: 10px auto 0;
  padding: 16px 0 22px;
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
  scroll-behavior: smooth;
}

#chat-box::-webkit-scrollbar,
.sidebar::-webkit-scrollbar {
  width: 8px;
}

#chat-box::-webkit-scrollbar-track,
.sidebar::-webkit-scrollbar-track {
  background: transparent;
}

#chat-box::-webkit-scrollbar-thumb,
.sidebar::-webkit-scrollbar-thumb {
  background: rgba(15, 23, 42, 0.15);
  border-radius: 999px;
}

.message {
  max-width: min(100%, 760px);
  padding: 14px 16px;
  border-radius: 18px;
  line-height: 1.65;
  font-size: 15px;
  border: 1px solid var(--border);
  background: var(--panel);
  box-shadow: var(--shadow-soft);
  animation: msg-in 0.22s ease-out;
  backdrop-filter: blur(16px);
}

@keyframes msg-in {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.message.user {
  align-self: flex-end;
  background: rgba(100, 181, 255, 0.08);
  border-bottom-right-radius: 6px;
}

.message.ai {
  align-self: flex-start;
  background: rgba(255, 255, 255, 0.05);
  border-bottom-left-radius: 6px;
}

.message.system {
  align-self: center;
  max-width: 92%;
  font-size: 12px;
  color: var(--text-2);
  background: rgba(255, 255, 255, 0.04);
}

.message p,
.message ul,
.message ol {
  margin: 0.5em 0;
}

.message code {
  padding: 1px 6px;
  border-radius: 6px;
  background: rgba(15, 23, 42, 0.06);
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px;
}

.message pre {
  overflow-x: auto;
  padding: 12px;
  border-radius: 14px;
  background: rgba(15, 23, 42, 0.05);
}

.message.thinking {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  width: max-content;
  padding: 12px 14px;
}

.message.thinking .dot {
  width: 7px;
  height: 7px;
  border-radius: 999px;
  background: var(--accent-2);
  opacity: 0.35;
  animation: bob 1.1s infinite ease-in-out;
}

.message.thinking .dot:nth-child(2) {
  animation-delay: 0.16s;
}

.message.thinking .dot:nth-child(3) {
  animation-delay: 0.32s;
}

@keyframes bob {
  0%,
  80%,
  100% {
    transform: translateY(0);
    opacity: 0.35;
  }
  40% {
    transform: translateY(-5px);
    opacity: 1;
  }
}

/* ── Voice visualizer ─────────────────────────────────────────────────────── */
.voice-visualizer {
  width: min(var(--max-chat), calc(100% - 32px));
  margin: 0 auto;
  height: 0;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  transition: height 0.22s ease;
}

.voice-visualizer.active {
  height: 52px;
}

.viz-bar {
  width: 4px;
  height: 6px;
  border-radius: 999px;
  background: linear-gradient(180deg, rgba(37, 99, 235, 0.95), rgba(15, 23, 42, 0.55));
  transition: height 0.08s ease;
}

/* ── Controls ─────────────────────────────────────────────────────────────── */
.controls {
  width: min(var(--max-chat), calc(100% - 32px));
  margin: 12px auto 18px;
  padding: 14px;
  border: 1px solid var(--border);
  border-radius: 24px;
  background: rgba(8, 12, 20, 0.78);
  backdrop-filter: blur(18px);
  box-shadow: var(--shadow);
  flex-shrink: 0;
}

.text-row {
  display: flex;
  align-items: flex-end;
  gap: 10px;
  margin-bottom: 10px;
}

#text-input {
  flex: 1;
  min-height: 46px;
  max-height: 220px;
  resize: none;
  overflow-y: auto;
  padding: 12px 14px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  line-height: 1.55;
}

#text-input::placeholder {
  color: var(--text-3);
}

#send-btn {
  width: 48px;
  height: 46px;
  border-radius: 16px;
  background: linear-gradient(135deg, #64b5ff, #8b5cf6);
  color: #05070d;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.voice-row {
  display: flex;
  gap: 10px;
}

.mic-btn {
  flex: 1;
  min-height: 48px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  cursor: pointer;
  padding: 0 16px;
}

.mic-btn.mic-listening {
  border-color: rgba(37, 99, 235, 0.35);
  box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.08);
}

.mic-btn.mic-recording {
  border-color: rgba(239, 68, 68, 0.35);
  box-shadow: 0 0 0 4px rgba(239, 68, 68, 0.08);
}

.mic-btn.mic-processing {
  border-color: rgba(217, 119, 6, 0.35);
  box-shadow: 0 0 0 4px rgba(217, 119, 6, 0.08);
}

.mic-icon {
  font-size: 18px;
}

.stop-btn {
  min-width: 90px;
  height: 48px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.04);
  color: #ff8da1;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  cursor: pointer;
  padding: 0 14px;
}

/* ── Brain mode ───────────────────────────────────────────────────────────── */
.brain-stage {
  display: none;
  width: min(560px, calc(100% - 24px));
  margin: 14px auto 0;
  flex: 1;
  align-items: center;
  justify-content: center;
  position: relative;
}

.brain-shell {
  position: relative;
  width: min(560px, 100%);
  height: min(74vh, 760px);
  border-radius: 40px;
  background:
    radial-gradient(circle at 50% 40%, rgba(100, 181, 255, 0.18), transparent 20%),
    radial-gradient(circle at 50% 62%, rgba(139, 92, 246, 0.14), transparent 38%),
    radial-gradient(circle at 50% 50%, rgba(15, 23, 42, 0.96), rgba(5, 7, 13, 1) 74%);
  border: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.brain-bubbles {
  position: absolute;
  inset: 0;
  z-index: 3;
  pointer-events: none;
  padding: 18px;
}

.brain-bubble {
  position: absolute;
  width: min(320px, calc(100% - 36px));
  min-height: 102px;
  padding: 16px 18px;
  border-radius: 24px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.06), rgba(255, 255, 255, 0.03)),
    rgba(8, 12, 20, 0.82);
  backdrop-filter: blur(18px);
  box-shadow: 0 18px 50px rgba(0, 0, 0, 0.35);
  transform: translateY(8px) scale(0.96);
  opacity: 0.78;
  transition: transform 0.25s ease, opacity 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease;
}

.brain-bubble::after {
  content: '';
  position: absolute;
  inset: auto 18px -8px auto;
  width: 16px;
  height: 16px;
  background: inherit;
  border-right: 1px solid rgba(255, 255, 255, 0.08);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  transform: rotate(45deg);
}

.brain-bubble-label {
  font-size: 10px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-3);
  margin-bottom: 8px;
}

.brain-bubble-text {
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  min-height: 40px;
  white-space: pre-wrap;
  word-break: break-word;
}

.brain-bubble-stt {
  left: 18px;
  top: 18px;
}

.brain-bubble-tts {
  right: 18px;
  bottom: 18px;
}

.brain-bubble.active {
  opacity: 1;
  transform: translateY(0) scale(1);
  border-color: rgba(100, 181, 255, 0.28);
  box-shadow:
    0 22px 62px rgba(0, 0, 0, 0.48),
    0 0 0 1px rgba(100, 181, 255, 0.08);
}

.brain-bubble.active .brain-bubble-label {
  color: rgba(100, 181, 255, 0.82);
}

.brain-bubble.speaking {
  animation: bubble-breathe 1.4s ease-in-out infinite;
}

.brain-bubble.speaking .brain-bubble-text {
  position: relative;
}

.brain-bubble.speaking .brain-bubble-text::after {
  content: '';
  display: inline-block;
  width: 10px;
  height: 10px;
  margin-left: 8px;
  border-radius: 999px;
  background: linear-gradient(135deg, #64b5ff, #8b5cf6);
  box-shadow: 0 0 0 0 rgba(100, 181, 255, 0.26);
  animation: bubble-dot 1s ease-in-out infinite;
}

.brain-scan {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, transparent 0%, rgba(100, 181, 255, 0.12) 50%, transparent 100%),
    linear-gradient(90deg, transparent 0%, rgba(100, 181, 255, 0.22) 48%, rgba(139, 92, 246, 0.22) 52%, transparent 100%);
  background-size: 100% 180px, 280px 100%;
  background-repeat: repeat-y, no-repeat;
  mix-blend-mode: screen;
  opacity: 0.55;
  animation: scan 6s linear infinite;
  pointer-events: none;
}

.brain-shell::before,
.brain-shell::after {
  content: '';
  position: absolute;
  inset: -20%;
  background:
    radial-gradient(circle at 30% 30%, rgba(100, 181, 255, 0.18), transparent 14%),
    radial-gradient(circle at 70% 40%, rgba(139, 92, 246, 0.12), transparent 16%),
    radial-gradient(circle at 55% 68%, rgba(22, 163, 74, 0.11), transparent 15%);
  animation: drift 16s linear infinite;
  pointer-events: none;
}

.brain-shell::after {
  animation-direction: reverse;
  opacity: 0.7;
}

.brain-pulse {
  position: absolute;
  inset: 50% auto auto 50%;
  width: 16px;
  height: 16px;
  border-radius: 999px;
  border: 1px solid rgba(100, 181, 255, 0.55);
  box-shadow: 0 0 0 0 rgba(100, 181, 255, 0.22);
  transform: translate(-50%, -50%);
  animation: pulse-ring 3.6s linear infinite;
  pointer-events: none;
}

.pulse-a {
  width: 110px;
  height: 110px;
}

.pulse-b {
  width: 220px;
  height: 220px;
  animation-delay: 0.8s;
}

.pulse-c {
  width: 340px;
  height: 340px;
  animation-delay: 1.6s;
}

.brain-svg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  filter: drop-shadow(0 0 16px rgba(37, 99, 235, 0.08));
}

.brain-outline {
  fill: rgba(255, 255, 255, 0.04);
  stroke: rgba(255, 255, 255, 0.12);
  stroke-width: 2;
  stroke-dasharray: 10 12;
  animation: pulse-line 8s linear infinite;
}

.brain-wire {
  fill: none;
  stroke: url(#brainGlow);
  stroke-width: 2.5;
  stroke-linecap: round;
  stroke-dasharray: 10 10;
  animation: dash 7s linear infinite;
  opacity: 0.82;
}

.brain-node {
  fill: rgba(255, 255, 255, 0.9);
  stroke: rgba(100, 181, 255, 0.35);
  stroke-width: 2;
  filter: drop-shadow(0 0 12px rgba(100, 181, 255, 0.38));
  animation: node-pulse 2.4s ease-in-out infinite;
  transform-box: fill-box;
  transform-origin: center;
}

.node-2,
.node-5,
.node-8,
.node-11 {
  animation-delay: 0.2s;
}

.node-3,
.node-6,
.node-9,
.node-12 {
  animation-delay: 0.4s;
}

.brain-core {
  fill: rgba(100, 181, 255, 0.18);
  stroke: rgba(100, 181, 255, 0.65);
  stroke-width: 2;
  animation: core-breath 2.8s ease-in-out infinite;
  transform-box: fill-box;
  transform-origin: center;
}

.brain-core.ring {
  fill: none;
  stroke: rgba(255, 255, 255, 0.12);
  stroke-dasharray: 8 12;
  animation: dash 9s linear infinite;
}

@keyframes dash {
  to {
    stroke-dashoffset: -120;
  }
}

@keyframes pulse-line {
  0%,
  100% {
    opacity: 0.65;
  }
  50% {
    opacity: 1;
  }
}

@keyframes node-pulse {
  0%,
  100% {
    transform: scale(1);
    opacity: 0.84;
  }
  50% {
    transform: scale(1.18);
    opacity: 1;
  }
}

@keyframes core-breath {
  0%,
  100% {
    transform: scale(1);
    opacity: 0.7;
  }
  50% {
    transform: scale(1.08);
    opacity: 1;
  }
}

@keyframes drift {
  0% {
    transform: translate3d(0, 0, 0) scale(1);
  }
  50% {
    transform: translate3d(3%, -2%, 0) scale(1.02);
  }
  100% {
    transform: translate3d(0, 0, 0) scale(1);
  }
}

@keyframes scan {
  0% {
    transform: translateY(-20%);
  }
  100% {
    transform: translateY(20%);
  }
}

@keyframes pulse-ring {
  0% {
    opacity: 0.15;
    transform: translate(-50%, -50%) scale(0.75);
  }
  50% {
    opacity: 0.75;
    transform: translate(-50%, -50%) scale(1);
  }
  100% {
    opacity: 0.12;
    transform: translate(-50%, -50%) scale(1.28);
  }
}

@keyframes bubble-breathe {
  0%,
  100% {
    transform: translateY(0) scale(1);
  }
  50% {
    transform: translateY(-2px) scale(1.015);
  }
}

@keyframes bubble-dot {
  0%,
  100% {
    transform: scale(0.75);
    opacity: 0.35;
  }
  50% {
    transform: scale(1);
    opacity: 1;
  }
}

body.brain-mode .sidebar,
body.brain-mode #chat-box,
body.brain-mode .voice-caption,
body.brain-mode .voice-visualizer {
  display: none;
}

body.brain-mode .brain-stage {
  display: flex;
}

body.brain-mode .controls {
  display: block;
  position: fixed;
  left: 50%;
  bottom: 18px;
  transform: translateX(-50%);
  width: min(420px, calc(100% - 24px));
  margin: 0;
  padding: 12px;
  background: rgba(5, 7, 13, 0.78);
  border-color: rgba(255, 255, 255, 0.08);
}

body.brain-mode .text-row {
  display: none;
}

body.brain-mode .voice-row {
  display: flex;
}

body.brain-mode .mic-btn,
body.brain-mode .stop-btn {
  background: rgba(255, 255, 255, 0.05);
}

body.brain-mode .topbar {
  background: rgba(5, 7, 13, 0.45);
  border-bottom-color: transparent;
}

body.brain-mode .topbar-center,
body.brain-mode #state-label {
  opacity: 0;
  pointer-events: none;
}

body.brain-mode .clear-btn {
  width: 40px;
  padding: 0;
  font-size: 0;
  color: transparent;
  background: rgba(255, 255, 255, 0.05);
}

body.brain-mode .clear-btn::before {
  content: '↺';
  font-size: 13px;
  color: var(--text);
}

body.brain-mode .brain-shell {
  box-shadow:
    0 30px 80px rgba(0, 0, 0, 0.5),
    inset 0 0 0 1px rgba(255, 255, 255, 0.03);
}

body.brain-mode .brain-bubble.active {
  transform: translateY(0) scale(1);
}

body.brain-mode .brain-pulse {
  border-color: rgba(100, 181, 255, 0.35);
}

body.brain-mode .brain-stage.searching .brain-wire {
  stroke-width: 3.2;
  opacity: 1;
  animation-duration: 2.2s;
}

body.brain-mode .brain-stage.searching .brain-core {
  animation-duration: 1.8s;
  filter: drop-shadow(0 0 18px rgba(100, 181, 255, 0.45));
}

body.brain-mode .brain-stage.searching .brain-node {
  animation-duration: 1.2s;
}

body.brain-mode .brain-stage[data-state='listening'] .brain-shell {
  box-shadow:
    0 30px 80px rgba(0, 0, 0, 0.46),
    0 0 0 1px rgba(100, 181, 255, 0.08),
    0 0 34px rgba(100, 181, 255, 0.12);
}

body.brain-mode .brain-stage[data-state='processing'] .brain-shell::before {
  animation-duration: 8s;
  filter: blur(0.3px);
}

body.brain-mode .brain-stage[data-state='speaking'] .brain-core {
  fill: rgba(100, 181, 255, 0.26);
  animation-duration: 1.4s;
}

body.brain-mode .brain-stage[data-state='speaking'] .brain-node {
  filter: drop-shadow(0 0 14px rgba(100, 181, 255, 0.52));
}

/* ── Responsive ───────────────────────────────────────────────────────────── */
@media (max-width: 960px) {
  .sidebar {
    position: fixed;
    inset: 0 auto 0 0;
    transform: translateX(-100%);
    z-index: 30;
    box-shadow: var(--shadow);
    transition: transform 0.2s ease;
  }

  .sidebar.mobile-open {
    transform: translateX(0);
  }

  .mobile-menu-btn {
    display: inline-flex;
  }

  .topbar-center {
    font-size: 13px;
  }

  .brain-shell {
    height: min(68vh, 620px);
  }
}

@media (max-width: 720px) {
  .topbar {
    padding: 12px 12px;
  }

  .topbar-state {
    padding: 7px 10px;
  }

  .clear-btn {
    padding: 0 12px;
  }

  .voice-caption,
  #chat-box,
  .controls,
  .voice-visualizer,
  .brain-stage {
    width: calc(100% - 20px);
  }

  #chat-box {
    padding-top: 12px;
  }

  .message {
    font-size: 14px;
    padding: 12px 14px;
  }

  .controls {
    padding: 12px;
    border-radius: 20px;
  }

  .text-row {
    margin-bottom: 8px;
  }

  .voice-row {
    gap: 8px;
  }

  .brain-shell {
    width: 100%;
    height: 64vh;
    border-radius: 28px;
  }

  .brain-bubble {
    width: calc(100% - 30px);
  }
}