:root {
  --card-width: clamp(48px, 9vw, 92px);
  --card-height: calc(var(--card-width) * 1.45);
  --card-radius: clamp(6px, 1vw, 10px);
}

/* General Body and Game Container Styling */
body {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  margin: 0;
  padding: clamp(8px, 1.5vw, 18px);
  background: linear-gradient(to bottom right, #166534, #15803d, #10b981);
  color: #333;
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: flex-start;
  font-size: clamp(13px, 1.8vw, 16px);
}

#game-container {
  max-width: min(1120px, 100%);
  width: 100%;
  background-color: rgba(255, 255, 255, 0.12);
  padding: clamp(12px, 2vw, 20px);
  border-radius: 16px;
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.18);
}

/* Header and Scores */
header {
  text-align: center;
  margin-bottom: 24px;
}

header h1 {
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 700;
  color: white;
  margin-bottom: 8px;
}

.scores {
  display: flex;
  justify-content: center;
  gap: clamp(16px, 4vw, 40px);
  color: white;
  font-size: clamp(1rem, 2.2vw, 1.25rem);
  flex-wrap: wrap;
}
.score .icon {
  margin-right: 8px;
}

/* Message Area */
#message-area {
  background-color: rgba(255, 255, 255, 0.92);
  border-radius: 12px;
  padding: clamp(10px, 2vw, 16px);
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0 auto clamp(14px, 2.5vw, 22px) auto;
  justify-content: center;
  max-width: min(520px, 100%);
}
#message-area .icon {
  font-size: 1.25rem; /* w-5 h-5 */
  color: #2563eb; /* text-blue-600 */
}
#game-message {
  color: #1f2937; /* text-gray-800 */
  font-weight: 500; /* font-medium */
  font-size: 1rem; /* text-base */
}

/* Hand Areas (Computer & Player) */
#computer-area,
#player-area {
  margin-bottom: clamp(18px, 3vw, 28px);
  min-height: clamp(140px, 26vw, 200px);
}
#computer-area h3,
#player-area h3,
#playing-field h4 {
  color: white;
  font-size: 1.125rem; /* text-lg */
  font-weight: 600; /* font-semibold */
  margin-bottom: 8px;
  text-align: center;
}
.hand-area {
  display: flex;
  flex-wrap: wrap;
  gap: clamp(4px, 1vw, 12px);
  justify-content: center;
  min-height: clamp(96px, 20vw, 150px);
  padding: clamp(4px, 1vw, 10px);
  transition: min-height 0.3s ease;
}
.hand-info {
  text-align: center;
  margin-top: 8px;
  color: white;
  font-size: 0.875rem; /* text-sm */
}
.knock-status {
  margin-top: 4px;
  font-weight: bold;
  min-height: 20px; /* For consistent layout */
}
.knock-status.gin {
  color: #facc15; /* text-yellow-300 */
}
.knock-status.knock {
  color: #fb923c; /* text-orange-300 */
}

/* Playing Field (Stock & Discard) */
#playing-field {
  display: flex;
  justify-content: center;
  align-items: flex-start;
  gap: clamp(18px, 4vw, 42px);
  margin-bottom: clamp(18px, 3vw, 28px);
  flex-wrap: wrap;
}
#stock-pile-area,
#discard-pile-area {
  text-align: center;
}
#stock-pile-count,
#discard-pile-count {
  color: white;
  font-size: 0.75rem; /* text-xs */
  margin-top: 4px;
}

.card {
  width: var(--card-width);
  height: var(--card-height);
  border: 2px solid rgba(209, 213, 219, 0.9);
  border-radius: var(--card-radius);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition:
    transform 0.3s ease,
    box-shadow 0.3s ease,
    border-color 0.3s ease;
  font-size: clamp(0.75rem, 1.8vw, 0.95rem);
  font-weight: 700;
  background-color: white;
  user-select: none;
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.12);
  position: relative;
}
.card:hover:not(.back):not(.empty) {
  border-color: #9ca3af; /* hover:border-gray-400 */
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1); /* hover:shadow-md */
  transform: translateY(-2px); /* hover:-translate-y-1 */
}
.card.back {
  background-color: #2563eb; /* bg-blue-600 */
  border-color: #1d4ed8; /* border-blue-700 */
  color: white;
  font-size: 2rem;
}
.card.selected {
  background-color: #fef9c3;
  border-color: #fcd34d;
  transform: translateY(-8px);
  box-shadow: 0 12px 22px rgba(0, 0, 0, 0.2);
}
.card.dragged-over-slot {
  /* For styling the card in the slot being dragged over */
  background-color: #dcfce7; /* bg-green-100 or similar for slot highlight */
  border-color: #4ade80; /* border-green-400 */
  transform: scale(1.05);
}
.player-card-slot.drag-over-active {
  /* For the slot div itself */
  background-color: rgba(74, 222, 128, 0.3); /* bg-green-500 bg-opacity-30 */
  border-radius: 8px; /* To match card */
  outline: 2px dashed #4ade80;
}

.card-placeholder.empty {
  width: var(--card-width);
  height: var(--card-height);
  border: 2px dashed rgba(148, 163, 184, 0.8);
  border-radius: var(--card-radius);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #94a3b8;
  font-size: clamp(0.7rem, 1.7vw, 0.9rem);
}

.card .rank {
  font-size: 0.85rem; /* text-xs */
}
.card .suit {
  font-size: 1.25rem; /* md:text-lg */
}
.card.red-suit .rank,
.card.red-suit .suit {
  color: #dc2626; /* text-red-600 */
}
.card.black-suit .rank,
.card.black-suit .suit {
  color: #000000; /* text-black */
}

/* Draggable placeholder/ghost image */
.dragging {
  opacity: 0.5;
  border: 2px dashed #0ea5e9; /* Example */
}

/* Action Buttons */
#action-buttons {
  display: flex;
  justify-content: center;
  gap: clamp(12px, 3vw, 24px);
  margin-bottom: clamp(18px, 3vw, 28px);
  flex-wrap: wrap;
  min-height: clamp(44px, 5vw, 60px);
}
#action-buttons button {
  color: white;
  font-weight: 700;
  padding: clamp(8px, 1.6vw, 12px) clamp(14px, 3vw, 24px);
  border-radius: 999px;
  transition:
    transform 0.2s ease,
    background-color 0.2s ease,
    box-shadow 0.2s ease;
  cursor: pointer;
  font-size: clamp(0.85rem, 2vw, 1.05rem);
  border: none;
  box-shadow: 0 8px 16px rgba(15, 23, 42, 0.18);
}
#action-buttons button:hover:not(:disabled) {
  transform: translateY(-2px);
}
#new-game-button {
  background-color: #2563eb;
}
#new-game-button:hover:not(:disabled) {
  background-color: #1d4ed8;
}
#pass-button {
  background-color: #0ea5e9;
}
#pass-button:hover:not(:disabled) {
  background-color: #0284c7;
}
#knock-button {
  background-color: #f97316;
}
#knock-button:hover {
  background-color: #ea580c;
}
#action-buttons button:disabled {
  cursor: not-allowed;
  opacity: 0.6;
  transform: none;
  box-shadow: none;
}

/* Rules Area */
#rules-area {
  background-color: rgba(255, 255, 255, 0.9);
  border-radius: 8px;
  padding: 16px;
  font-size: 0.875rem; /* text-sm */
}
#rules-area h4 {
  font-weight: bold;
  margin-bottom: 8px;
  color: #1f2937; /* Overriding general h4 color for this section */
  text-align: left;
}
#rules-area ul {
  list-style-position: inside;
  padding-left: 0;
  margin: 0;
  space-y: 4px; /* Approximation */
  color: #374151; /* text-gray-700 */
}
#rules-area ul li {
  margin-bottom: 4px; /* Simulates space-y-1 */
}

/* Flying card animation overlay */
.flying-card {
  position: fixed;
  pointer-events: none;
  transition:
    transform 0.45s ease,
    opacity 0.45s ease;
  z-index: 1000;
  opacity: 1;
  will-change: transform, opacity;
}

.card-hidden {
  visibility: hidden;
}

/* Responsive adjustments (basic example) */
@media (max-width: 820px) {
  body {
    align-items: stretch;
  }
  #game-container {
    border-radius: 0;
    box-shadow: none;
  }
  #playing-field {
    flex-direction: column;
    align-items: center;
  }
  #stock-pile-area,
  #discard-pile-area {
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
  }
}

@media (max-width: 520px) {
  .hand-area {
    justify-content: flex-start;
    overflow-x: auto;
  }
  #action-buttons {
    gap: 12px;
  }
}

/* Player card slot wrapper for drag and drop */
.player-card-slot {
  /* No specific style needed unless for highlighting drop target */
  padding: 2px; /* To provide some space for drag-over highlight */
}