/* ── Rules Modal ── */
#rules-modal {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0, 0, 0, 0.92);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 200;
  backdrop-filter: blur(8px);
}

#rules-modal.hidden,
#back-to-game-btn.hidden {
  display: none;
}

.rules-content {
  max-width: 520px;
  max-height: 90vh;
  overflow-y: auto;
  width: 90%;
  padding: 35px;
  background: rgba(10, 10, 25, 0.95);
  border: 2px solid #00f3ff;
  border-radius: 12px;
  box-shadow:
    0 0 30px rgba(0, 243, 255, 0.4),
    inset 0 0 20px rgba(0, 243, 255, 0.1);
}

.rules-title {
  font-size: 28px;
  color: #00f3ff;
  text-align: center;
  letter-spacing: 4px;
  text-shadow: 0 0 20px rgba(0, 243, 255, 0.6);
  margin-bottom: 8px;
}

.rules-divider {
  height: 2px;
  background: linear-gradient(90deg, transparent, #00f3ff, transparent);
  margin-bottom: 20px;
}

.rules-section {
  margin-bottom: 18px;
}

.rules-heading {
  font-size: 14px;
  color: #fff; /* NOSONAR */
  letter-spacing: 2px;
  margin-bottom: 8px;
  text-shadow: 0 0 8px rgba(255, 0, 85, 0.4);
}

.rules-content p {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.8);
  line-height: 1.6;
}

.rules-list {
  list-style: none;
  padding: 0;
}

.rules-list li {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.8);
  padding: 4px 0;
  padding-left: 18px;
  position: relative;
  line-height: 1.5;
}

.rules-list li::before {
  content: "\25B8";
  position: absolute;
  left: 0;
  color: #00f3ff;
}

/* ── Game Mode Toggle ── */
.mode-toggle {
  display: flex;
  gap: 8px;
  margin-bottom: 8px;
}

.mode-btn {
  flex: 1;
  background: rgba(0, 0, 0, 0.6);
  border: 2px solid rgba(255, 255, 255, 0.15);
  border-radius: 6px;
  padding: 10px;
  color: rgba(255, 255, 255, 0.5);
  font-family: 'Courier New', monospace;
  font-size: 14px;
  font-weight: bold;
  letter-spacing: 2px;
  cursor: pointer;
  transition: all 0.3s ease;
}

.mode-btn:hover {
  border-color: rgba(255, 255, 255, 0.3);
}

.mode-btn.active[data-mode="classic"] {
  color: #003d42;
  border-color: #00f3ff;
  background: rgba(0, 243, 255, 0.4);
  box-shadow: 0 0 12px rgba(0, 243, 255, 0.3);
}

.mode-btn.active[data-mode="blitz"] {
  color: #3d2a00;
  border-color: #ffff00;
  background: rgba(255, 200, 0, 0.75);
  box-shadow: 0 0 12px rgba(255, 255, 0, 0.3);
  text-shadow: none;
}

.mode-desc {
  font-family: 'Courier New', monospace;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.4);
  letter-spacing: 1px;
  margin-bottom: 0;
}

/* ── Difficulty Select ── */
.difficulty-select {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-top: 10px;
}

.diff-btn {
  background: rgba(0, 0, 0, 0.6);
  border: 2px solid rgba(0, 243, 255, 0.3);
  border-radius: 8px;
  padding: 14px 8px;
  cursor: pointer;
  transition: all 0.3s ease;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
}

.diff-btn:hover {
  border-color: #00f3ff;
  box-shadow: 0 0 15px rgba(0, 243, 255, 0.3);
}

.diff-btn.active {
  border-color: #00f3ff;
  background: rgba(0, 243, 255, 0.4);
  box-shadow: 0 0 20px rgba(0, 243, 255, 0.4);
}

.diff-name {
  font-family: 'Courier New', monospace;
  font-size: 16px;
  font-weight: bold;
  color: #00f3ff;
  letter-spacing: 2px;
}

.diff-desc {
  font-family: 'Courier New', monospace;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.5);
  letter-spacing: 1px;
}

.diff-btn[data-difficulty="easy"] .diff-name { color: #00f3ff; }
.diff-btn[data-difficulty="medium"] .diff-name { color: #fff; /* NOSONAR */ }
.diff-btn[data-difficulty="hard"] .diff-name { color: #fff; /* NOSONAR */ text-shadow: 0 0 10px rgba(255, 0, 85, 0.6); }
.diff-btn[data-difficulty="extreme"] .diff-name { color: #ff0000; text-shadow: 0 0 12px rgba(255, 0, 0, 0.8); letter-spacing: 3px; }

.diff-btn[data-difficulty="easy"]:hover,
.diff-btn[data-difficulty="easy"].active { border-color: #00f3ff; }
.diff-btn[data-difficulty="medium"]:hover,
.diff-btn[data-difficulty="medium"].active { border-color: #fff; /* NOSONAR */ box-shadow: 0 0 20px rgba(255, 0, 85, 0.4); background: rgba(255, 0, 85, 0.1); }
.diff-btn[data-difficulty="hard"]:hover,
.diff-btn[data-difficulty="hard"].active { border-color: #fff; /* NOSONAR */ box-shadow: 0 0 25px rgba(255, 0, 85, 0.5); background: rgba(255, 0, 85, 0.15); }
.diff-btn[data-difficulty="extreme"]:hover,
.diff-btn[data-difficulty="extreme"].active { border-color: #ff0000; box-shadow: 0 0 30px rgba(255, 0, 0, 0.6); background: rgba(255, 0, 0, 0.15); }

.diff-best {
  font-family: 'Courier New', monospace;
  font-size: 14px;
  color: #00ff88;
  letter-spacing: 1px;
  text-shadow: 0 0 6px rgba(0, 255, 136, 0.4);
}

#back-to-game-btn {
  display: block;
  width: 100%;
  margin-top: 15px;
  background: transparent;
  color: #00f3ff;
  border: 2px solid #00f3ff;
  padding: 10px;
  font-family: 'Courier New', monospace;
  font-size: 14px;
  font-weight: bold;
  cursor: pointer;
  text-transform: uppercase;
  letter-spacing: 2px;
  transition: all 0.3s ease;
  box-shadow: 0 0 10px rgba(0, 243, 255, 0.3);
}

#back-to-game-btn:hover {
  background: #00f3ff;
  color: #000; /* NOSONAR - hover state has bright background */
  box-shadow: 0 0 20px #00f3ff;
}