/* ═══════════════════════════════════════════════════════════════
   Spark Dark — Qwen3.5-0.8B WebGPU Demo
   Design tokens inspired by Spark Design System (dark variant)
   ═══════════════════════════════════════════════════════════════ */

@import url('https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@400;500;600&family=Plus+Jakarta+Sans:wght@400;500;600;700;800&display=swap');

/* ── Design Tokens ─────────────────────────────────────────── */
:root {
  /* Surfaces */
  --spark-bg-root:       #08090c;
  --spark-bg-panel:      #10121a;
  --spark-bg-card:       #161926;
  --spark-bg-elevated:   #1c2033;
  --spark-bg-input:      #0d0f16;
  --spark-bg-hover:      #1f2340;

  /* Borders */
  --spark-border:        rgba(255, 255, 255, 0.06);
  --spark-border-focus:  rgba(120, 100, 255, 0.50);

  /* Accent — electric violet */
  --spark-accent:        #8b6eff;
  --spark-accent-light:  #b8a4ff;
  --spark-accent-dim:    rgba(139, 110, 255, 0.18);
  --spark-accent-glow:   rgba(139, 110, 255, 0.40);

  /* Semantic */
  --spark-success:       #34d399;
  --spark-warning:       #fbbf24;
  --spark-danger:        #f87171;

  /* Text */
  --spark-text-1:        #ecedf4;
  --spark-text-2:        #9698ad;
  --spark-text-3:        #7e8099;

  /* Typography */
  --font-sans:  'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono:  'JetBrains Mono', 'SF Mono', Consolas, monospace;

  /* Radii */
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;

  /* Shadows */
  --shadow-card:  0 2px 8px rgba(0,0,0,.35), 0 12px 40px rgba(0,0,0,.25);
  --shadow-glow:  0 0 30px var(--spark-accent-glow);
  --shadow-input: inset 0 1px 3px rgba(0,0,0,.4);
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background: var(--spark-bg-root);
  color: var(--spark-text-1);
  min-height: 100vh;
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 24px 16px 40px;
  gap: 20px;
  overflow-x: hidden;

  /* subtle grid texture */
  background-image:
    linear-gradient(rgba(124,92,252,0.018) 1px, transparent 1px),
    linear-gradient(90deg, rgba(124,92,252,0.018) 1px, transparent 1px);
  background-size: 48px 48px;
}

/* ── Header ────────────────────────────────────────────────── */
.header {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
}

.header__badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  border-radius: 999px;
  background: var(--spark-accent-dim);
  border: 1px solid rgba(124, 92, 252, 0.2);
  color: var(--spark-accent-light);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.header__badge::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--spark-accent);
  box-shadow: 0 0 8px var(--spark-accent);
  animation: pulse-dot 2s ease-in-out infinite;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50%      { opacity: .5; transform: scale(0.8); }
}

.header__title {
  font-size: clamp(1.5rem, 4vw, 2.25rem);
  font-weight: 800;
  letter-spacing: -0.035em;
  background: linear-gradient(135deg, #ecedf4 30%, var(--spark-accent-light) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.15;
}

.header__subtitle {
  color: var(--spark-text-3);
  font-size: 0.82rem;
  font-weight: 500;
}

/* ── Video Container ───────────────────────────────────────── */
.video-wrap {
  position: relative;
  width: min(92vw, 680px);
  aspect-ratio: 4 / 3;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--spark-border);
  background: #000;
  box-shadow: var(--shadow-card);
}

.video-wrap.is-processing {
  border-color: var(--spark-accent);
  box-shadow: var(--shadow-card), 0 0 24px var(--spark-accent-glow);
  transition: border-color .3s, box-shadow .3s;
}

.video-wrap::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
  box-shadow: inset 0 0 0 1px rgba(255,255,255,0.04);
}

#videoFeed {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: inherit;
}

/* overlay shared pill style */
.video-pill {
  position: absolute;
  z-index: 11;
  padding: 5px 12px;
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 600;
  backdrop-filter: blur(12px) saturate(1.4);
  -webkit-backdrop-filter: blur(12px) saturate(1.4);
  border: 1px solid rgba(255,255,255,0.1);
  transition: opacity .2s, background .2s;
}

/* Source toggle */
#sourceToggleButton {
  top: 10px;
  left: 10px;
  z-index: 12;
  background: rgba(10, 12, 20, 0.75);
  color: #fff;
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
}
.video-wrap:hover #sourceToggleButton,
.video-wrap:focus-within #sourceToggleButton {
  opacity: 1;
  pointer-events: auto;
}
#sourceToggleButton:hover:not(:disabled) {
  background: rgba(124, 92, 252, 0.35);
}
#sourceToggleButton:disabled {
  opacity: .35;
  cursor: not-allowed;
}

/* Prefill indicator */
#prefillIndicator {
  top: 10px;
  right: 10px;
  display: none;
  align-items: center;
  gap: 7px;
  background: rgba(10, 12, 20, 0.80);
  color: var(--spark-accent-light);
}
#prefillIndicator.active { display: inline-flex; }

/* Loading overlay */
#loadingOverlay {
  position: absolute;
  inset: 0;
  display: none;
  justify-content: center;
  align-items: center;
  flex-direction: column;
  gap: 14px;
  background: rgba(8, 9, 12, 0.88);
  z-index: 10;
  border-radius: inherit;
  color: var(--spark-text-2);
  font-size: 0.9rem;
  font-weight: 600;
}

.loading-spinner-ring {
  width: 36px;
  height: 36px;
  border: 3px solid rgba(124, 92, 252, 0.15);
  border-top-color: var(--spark-accent);
  border-radius: 50%;
  animation: spin .9s linear infinite;
}

/* Prefill mini spinner */
.spinner-sm {
  width: 10px;
  height: 10px;
  border: 2px solid rgba(155, 130, 253, 0.25);
  border-top-color: var(--spark-accent-light);
  border-radius: 50%;
  animation: spin .8s linear infinite;
}

@keyframes spin { to { transform: rotate(360deg); } }

/* ── Controls Panel ────────────────────────────────────────── */
.controls {
  width: min(92vw, 680px);
  background: var(--spark-bg-panel);
  border: 1px solid var(--spark-border);
  border-radius: var(--radius-lg);
  padding: 16px 18px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  box-shadow: var(--shadow-card);
}

/* Field row */
.field {
  display: flex;
  flex-direction: column;
  gap: 5px;
}

.field__label {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--spark-text-3);
}

/* Input row (instruction + button) */
.input-row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 10px;
  align-items: flex-end;
}

/* Textarea */
textarea {
  width: 100%;
  padding: 10px 14px;
  background: var(--spark-bg-input);
  border: 1px solid var(--spark-border);
  border-radius: var(--radius-sm);
  color: var(--spark-text-1);
  font-family: var(--font-sans);
  font-size: 0.85rem;
  line-height: 1.45;
  resize: none;
  transition: border-color .2s, box-shadow .2s;
  box-shadow: var(--shadow-input);
}
textarea:focus {
  outline: none;
  border-color: var(--spark-border-focus);
  box-shadow: var(--shadow-input), 0 0 0 3px var(--spark-accent-dim);
}
textarea[readonly] {
  color: var(--spark-text-2);
  cursor: default;
}
textarea::placeholder {
  color: var(--spark-text-3);
}

.instruction-input {
  min-height: 2.6em;
  overflow: hidden;
}

.response-area {
  min-height: calc(1.45em * 3 + 20px);
  max-height: calc(1.45em * 5 + 20px);
  overflow-y: auto;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.55;
}

/* Custom scrollbar for response */
.response-area::-webkit-scrollbar { width: 5px; }
.response-area::-webkit-scrollbar-track { background: transparent; }
.response-area::-webkit-scrollbar-thumb {
  background: var(--spark-accent-dim);
  border-radius: 10px;
}

/* ── Start / Stop Button ──────────────────────────────────── */
.btn-action {
  min-width: 90px;
  height: 40px;
  padding: 0 18px;
  border: none;
  border-radius: var(--radius-sm);
  font-family: var(--font-sans);
  font-size: 0.82rem;
  font-weight: 700;
  cursor: pointer;
  transition: transform .12s, box-shadow .25s, background .2s;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  letter-spacing: 0.02em;
}

.btn-action:hover:not(:disabled) {
  transform: translateY(-1px);
}

.btn-action:active:not(:disabled) {
  transform: translateY(0);
}

.btn-action:disabled {
  opacity: .45;
  cursor: not-allowed;
}

.btn-action.is-start {
  background: var(--spark-accent);
  color: #fff;
  box-shadow: 0 4px 18px rgba(124, 92, 252, 0.35);
}
.btn-action.is-start:hover:not(:disabled) {
  box-shadow: 0 6px 24px rgba(124, 92, 252, 0.50);
}

.btn-action.is-stop {
  background: var(--spark-danger);
  color: #fff;
  box-shadow: 0 4px 18px rgba(248, 113, 113, 0.3);
}
.btn-action.is-stop:hover:not(:disabled) {
  box-shadow: 0 6px 24px rgba(248, 113, 113, 0.45);
}

/* ── Status Bar ────────────────────────────────────────────── */
.status-bar {
  width: min(92vw, 680px);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.status-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  border-radius: 999px;
  background: var(--spark-bg-card);
  border: 1px solid var(--spark-border);
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--spark-text-3);
}

.status-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--spark-text-3);
  transition: background .3s, box-shadow .3s;
}
.status-dot.online {
  background: var(--spark-success);
  box-shadow: 0 0 8px rgba(52, 211, 153, 0.5);
}
.status-dot.loading {
  background: var(--spark-warning);
  animation: pulse-dot 1.2s ease-in-out infinite;
}
.status-dot.error {
  background: var(--spark-danger);
}

.webgpu-tag {
  padding: 3px 10px;
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 0.62rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  background: rgba(52, 211, 153, 0.1);
  color: var(--spark-success);
  border: 1px solid rgba(52, 211, 153, 0.15);
}

/* ── Footer ───────────────────────────────────────────────── */
.footer {
  color: var(--spark-text-3);
  font-size: 0.75rem;
  text-align: center;
}

.footer a {
  color: var(--spark-accent-light);
  text-decoration: none;
}

.footer a:hover {
  text-decoration: underline;
}

/* ── WebGPU Warning ───────────────────────────────────────── */
.webgpu-warning {
  width: min(92vw, 680px);
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  background: rgba(248, 113, 113, 0.1);
  border: 1px solid rgba(248, 113, 113, 0.2);
  color: var(--spark-danger);
  font-size: 0.85rem;
  text-align: center;
}

/* ── Mobile Disclaimer ────────────────────────────────────── */
.mobile-disclaimer {
  position: fixed;
  inset: 0;
  z-index: 9999;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  padding: 32px;
  background: var(--spark-bg-root);
  color: var(--spark-text-1);
  text-align: center;
}

.mobile-disclaimer__title {
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.mobile-disclaimer__body {
  max-width: 360px;
  color: var(--spark-text-2);
  font-size: 0.9rem;
  line-height: 1.6;
}

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

/* ── Responsive ────────────────────────────────────────────── */
@media (max-width: 640px) {
  body { padding: 14px 10px 30px; gap: 14px; }

  .header__title { font-size: 1.3rem; }

  .input-row {
    grid-template-columns: 1fr;
  }

  .btn-action {
    width: 100%;
    height: 44px;
  }

  .controls { padding: 14px; }

  .status-bar {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }
}