/* ── Intro / Mission Briefing Overlay ─────────────────────────────────────── */

#intro-overlay {
  position: fixed;
  inset: 0;
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.82);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  font-family: Arial, sans-serif;
}

#intro-overlay.hidden {
  display: none;
}

.intro-box {
  width: min(560px, calc(100vw - 40px));
  background: rgba(4, 12, 22, 0.96);
  border: 1px solid rgba(0, 190, 255, 0.35);
  border-radius: 8px;
  box-shadow: 0 8px 40px rgba(0, 0, 0, 0.80);
  padding: 36px 40px 32px;
  display: flex;
  flex-direction: column;
  gap: 18px;
  text-align: center;
}

.intro-game-title {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.30em;
  text-transform: uppercase;
  color: rgba(0, 210, 255, 0.60);
}

.intro-headline {
  font-size: 28px;
  font-weight: 900;
  color: #fff;
  line-height: 1.2;
}

.intro-headline span {
  color: #ffd97a;
}

.intro-divider {
  width: 60px;
  height: 2px;
  background: rgba(0, 190, 255, 0.40);
  margin: 0 auto;
  border-radius: 2px;
}

.intro-body {
  font-size: 14px;
  color: #ccc;
  line-height: 1.7;
}

.intro-objectives {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
  text-align: left;
}

.intro-objectives li {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  font-size: 13px;
  color: #ddd;
  line-height: 1.5;
}

.intro-objectives li .obj-num {
  flex-shrink: 0;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: rgba(0, 190, 255, 0.15);
  border: 1px solid rgba(0, 190, 255, 0.40);
  color: rgba(0, 215, 255, 0.90);
  font-size: 11px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}

.intro-objectives li .obj-text strong {
  color: #fff;
}

.intro-win-condition {
  background: rgba(255, 215, 80, 0.07);
  border: 1px solid rgba(255, 215, 80, 0.28);
  border-radius: 6px;
  padding: 12px 16px;
  font-size: 13px;
  color: #ffd97a;
  line-height: 1.6;
}

.intro-win-condition strong {
  display: block;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(255, 215, 80, 0.60);
  margin-bottom: 4px;
}

.intro-btn-row {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  align-self: center;
}

.intro-start-btn {
  padding: 12px 48px;
  background: rgba(0, 180, 255, 0.12);
  border: 1px solid rgba(0, 200, 255, 0.45);
  border-radius: 4px;
  color: #fff;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s;
}

.intro-start-btn:hover {
  background: rgba(0, 200, 255, 0.24);
  border-color: rgba(0, 220, 255, 0.75);
}

.intro-skip-btn {
  padding: 12px 20px;
  background: none;
  border: 1px solid rgba(180, 180, 180, 0.25);
  border-radius: 4px;
  color: rgba(180, 180, 180, 0.55);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  cursor: pointer;
  transition: border-color 0.15s, color 0.15s;
}

.intro-skip-btn:hover {
  border-color: rgba(180, 180, 180, 0.55);
  color: rgba(220, 220, 220, 0.85);
}

.intro-toggle-row {
  display: flex;
  align-items: center;
  justify-content: center;
}

.intro-toggle-label {
  display: flex;
  align-items: center;
  gap: 10px;
  cursor: pointer;
  font-size: 13px;
  color: rgba(180, 180, 180, 0.70);
  user-select: none;
}

.intro-toggle-label input[type="checkbox"] {
  width: 16px;
  height: 16px;
  cursor: pointer;
  accent-color: #00c8ff;
  flex-shrink: 0;
}

.intro-toggle-label em {
  color: rgba(0, 200, 255, 0.55);
  font-style: normal;
}