/* Chess Opening Master V2 - Bright & Cheerful Duolingo-inspired Theme */
@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700;800&family=Plus+Jakarta+Sans:wght@300;400;500;600;700;800&display=swap');

:root {
    --bg-body: #f0f9ff; /* Light sky blue */
    --bg-gradient: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
    --bg-card: #ffffff;
    --bg-card-solid: #ffffff;
    --text-main: #1e293b; /* Dark slate */
    --text-muted: #64748b; /* Cool gray */
    --primary: #58cc02; /* Duolingo Green */
    --primary-btn: #3b8701; /* High-contrast green for buttons & active text */
    --primary-btn-hover: #2e6901;
    --primary-glow: rgba(88, 204, 2, 0.25);
    --primary-hover: #46a302;
    --success: #58cc02;
    --success-glow: rgba(88, 204, 2, 0.2);
    --error: #ff4b4b; /* Duolingo Red */
    --warning: #ffc800; /* Duolingo Yellow */
    --border: #e2e8f0;
    --border-active: #58cc02;
    --shadow-color: #cbd5e1;
    --shadow: 0 8px 0px 0px var(--shadow-color), 0 12px 24px rgba(0, 0, 0, 0.04);
    --font-sans: 'Plus Jakarta Sans', -apple-system, sans-serif;
    --font-title: 'Outfit', -apple-system, sans-serif;
    --transition: all 0.15s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    -webkit-tap-highlight-color: transparent;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}
::-webkit-scrollbar-track {
    background: transparent;
}
::-webkit-scrollbar-thumb {
    background: rgba(0, 0, 0, 0.1);
    border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
    background: rgba(0, 0, 0, 0.2);
}

body {
    font-family: var(--font-sans);
    background-color: var(--bg-body);
    background-image: var(--bg-gradient);
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    overflow-x: hidden;
}

#app-container {
    width: 100%;
    max-width: 480px;
    min-height: 100vh;
    background-color: #ffffff;
    border-left: 2px solid var(--border);
    border-right: 2px solid var(--border);
    box-shadow: 0 0 50px rgba(0,0,0,0.03);
    display: flex;
    flex-direction: column;
    position: relative;
    padding-bottom: 76px; /* Navigation height */
}

/* Screens */
.screen {
    display: none;
    flex-direction: column;
    flex: 1;
    padding: 24px;
    overflow-y: auto;
    animation: slideUp 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.screen.active {
    display: flex;
}

/* Animations */
@keyframes slideUp {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-6px); }
}

/* Typography */
h1, h2, h3, h4 {
    font-family: var(--font-title);
    font-weight: 800;
    letter-spacing: -0.01em;
}

.title {
    font-size: 2.2rem;
    font-weight: 800;
    background: linear-gradient(135deg, #58cc02 0%, #3b82f6 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 8px;
    letter-spacing: -0.02em;
}

.subtitle {
    text-align: center;
    color: var(--text-muted);
    font-size: 1rem;
    font-weight: 500;
    margin-bottom: 24px;
}

/* Duolingo style 3D Cards */
.card {
    background: var(--bg-card);
    border: 2px solid var(--border);
    border-bottom: 6px solid var(--border);
    border-radius: 20px;
    padding: 20px;
    margin-bottom: 20px;
    transition: var(--transition);
}

.card:hover {
    border-color: #cbd5e1;
}

/* Duolingo style tactile 3D Buttons */
.btn {
    background-color: var(--primary-btn);
    color: white;
    border: none;
    border-bottom: 4px solid var(--primary-btn-hover);
    padding: 14px 20px;
    border-radius: 16px;
    font-family: var(--font-sans);
    font-size: 1rem;
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    text-decoration: none;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.btn:hover {
    filter: brightness(1.05);
}

.btn:active {
    transform: translateY(2px);
    border-bottom-width: 2px;
}

.btn:disabled {
    background-color: #e2e8f0;
    color: #94a3b8;
    border: none;
    border-bottom: 4px solid #cbd5e1;
    cursor: not-allowed;
    transform: none;
}

.btn-secondary {
    background-color: #ffffff;
    color: #4b5563;
    border: 2px solid #e5e7eb;
    border-bottom: 4px solid #d1d5db;
}

.btn-secondary:hover {
    background-color: #f9fafb;
    filter: none;
}

.btn-secondary:active {
    transform: translateY(2px);
    border-bottom-width: 2px;
}

.btn-danger {
    background-color: var(--error);
    border-bottom: 4px solid #ea2b2b;
}

.btn-danger:active {
    transform: translateY(2px);
    border-bottom-width: 2px;
}

/* Bottom Navigation */
.nav-bar {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 76px;
    background: #ffffff;
    border-top: 2px solid var(--border);
    display: flex;
    justify-content: space-around;
    align-items: center;
    z-index: 90;
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: #475569; /* Darker grey for inactive state */
    text-decoration: none;
    font-size: 0.75rem;
    font-weight: 700;
    gap: 4px;
    flex: 1;
    height: 100%;
    cursor: pointer;
    transition: var(--transition);
}

.nav-item i {
    font-size: 1.5rem;
    transition: var(--transition);
}

.nav-item:hover, .nav-item.active {
    color: var(--primary-btn); /* High contrast active color */
}

.nav-item.active i {
    transform: scale(1.15);
    color: var(--primary-btn);
}

/* Home Screen Banner */
.hero-banner {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 24px 10px;
    text-align: center;
}

.hero-logo {
    font-size: 4.8rem;
    margin-bottom: 12px;
    animation: float 4s ease-in-out infinite;
}

/* Library List */
.library-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
    padding-bottom: 20px;
}

.opening-card {
    background: #ffffff;
    border: 2px solid var(--border);
    border-bottom: 5px solid var(--border);
    border-radius: 18px;
    padding: 16px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    transition: var(--transition);
}

.opening-card.unlocked {
    border-left: 5px solid var(--primary);
}

.opening-card.mastered {
    border-left-color: var(--warning);
}

.opening-card.locked {
    opacity: 0.6;
    cursor: not-allowed;
    background: #f8fafc;
}

.opening-card:not(.locked):hover {
    transform: translateY(-2px);
    border-color: #cbd5e1;
}

.opening-card:not(.locked):active {
    transform: translateY(1px);
    border-bottom-width: 3px;
}

.card-info {
    flex: 1;
}

.card-info h3 {
    font-size: 1.1rem;
    margin-bottom: 4px;
    color: var(--text-main);
}

.card-info p {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.progress-container {
    width: 100px;
    height: 8px;
    background: #e2e8f0;
    border-radius: 4px;
    overflow: hidden;
    margin-top: 8px;
}

.progress-fill {
    height: 100%;
    background: var(--primary);
    width: 0%;
    border-radius: 4px;
    transition: width 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.mastered .progress-fill {
    background: var(--warning);
}

/* Chessboard Styling (Vibrant Pastel Colors) */
#board-wrapper {
    width: 100%;
    aspect-ratio: 1;
    margin: 10px auto 20px auto;
    border-radius: 20px;
    overflow: hidden;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.08);
    border: 3px solid var(--border);
}

#board, #game-board {
    touch-action: none;
}

/* Custom Chessboard Squares colors */
.white-1e1d7 {
    background-color: #f8fafc !important; /* Creamy slate */
    color: #64748b !important;
}

.black-3c85d {
    background-color: #86efac !important; /* Cheerful light green */
    color: #ffffff !important;
}

.highlight-square {
    box-shadow: inset 0 0 0 6px rgba(255, 200, 0, 0.9) !important; /* Bright yellow highlights */
}

/* Visual Aids Highlights */
.square-55d63 {
    position: relative; /* Ensure dot positions correctly */
}

.legal-dot::after {
    content: '';
    position: absolute;
    width: 16px;
    height: 16px;
    background: rgba(88, 204, 2, 0.6); /* Cheerful Duolingo Green */
    border-radius: 50%;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    pointer-events: none;
    z-index: 10;
}

.legal-capture {
    box-shadow: inset 0 0 0 5px rgba(88, 204, 2, 0.85) !important;
}

.threat-square {
    box-shadow: inset 0 0 0 5px rgba(255, 75, 75, 0.7) !important; /* Bold red outline */
    background-color: rgba(255, 75, 75, 0.15) !important;
}

/* Head-to-Head Stats Cards */
.h2h-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: #f8fafc;
    border: 2px solid var(--border);
    border-radius: 16px;
    padding: 10px 14px;
    transition: var(--transition);
}

.h2h-row:hover {
    border-color: var(--primary);
}

.h2h-char-info {
    display: flex;
    align-items: center;
    gap: 10px;
}

.h2h-avatar-img {
    width: 36px;
    height: 36px;
    border-radius: 8px;
    border: 2px solid var(--border);
    background: #f1f5f9;
}

.h2h-name-box {
    display: flex;
    flex-direction: column;
    text-align: left;
}

.h2h-name {
    font-weight: 800;
    font-size: 0.85rem;
    color: var(--text-main);
}

.h2h-rating {
    font-size: 0.7rem;
    color: var(--text-muted);
    font-weight: 600;
}

.h2h-record-box {
    text-align: right;
    display: flex;
    flex-direction: column;
    align-items: flex-end;
}

.h2h-record {
    font-family: monospace;
    font-size: 0.85rem;
    font-weight: bold;
    color: var(--text-main);
}

.h2h-winrate-bar {
    width: 80px;
    height: 6px;
    background: #e2e8f0;
    border-radius: 3px;
    margin-top: 4px;
    overflow: hidden;
}

.h2h-winrate-fill {
    height: 100%;
    background: var(--primary);
    border-radius: 3px;
    width: 0%;
}

.feedback-area {
    text-align: center;
    min-height: 36px;
    margin-bottom: 12px;
    font-weight: 800;
    font-size: 1.2rem;
    letter-spacing: -0.01em;
}

.feedback-area.success {
    color: var(--primary);
}

.feedback-area.error {
    color: var(--error);
}

/* Game Info Display */
.game-info-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: #f8fafc;
    border: 2px solid var(--border);
    padding: 12px 18px;
    border-radius: 16px;
    margin-bottom: 14px;
}

.player-tag {
    display: flex;
    flex-direction: column;
}

.player-tag .name {
    font-weight: 800;
    font-size: 0.95rem;
}

.player-tag .elo {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-weight: 600;
}

.game-clock {
    font-family: monospace;
    font-size: 1.15rem;
    font-weight: bold;
    color: var(--text-main);
    background: #e2e8f0;
    padding: 4px 10px;
    border-radius: 8px;
    border: 1px solid #cbd5e1;
}

/* Matchmaking */
.matchmaker-setup {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.form-group label {
    font-size: 0.9rem;
    font-weight: 800;
    color: var(--text-main);
}

.select-control {
    background-color: #ffffff;
    border: 2px solid var(--border);
    border-bottom-width: 4px;
    color: var(--text-main);
    padding: 12px 16px;
    border-radius: 14px;
    font-family: var(--font-sans);
    font-size: 0.95rem;
    font-weight: 600;
    outline: none;
    cursor: pointer;
    transition: var(--transition);
}

.select-control:focus {
    border-color: var(--primary);
}

.color-picker {
    display: flex;
    gap: 12px;
}

.color-option {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    border: 2px solid var(--border);
    border-bottom: 4px solid var(--border);
    border-radius: 16px;
    padding: 12px;
    cursor: pointer;
    transition: var(--transition);
    background: #ffffff;
    font-weight: 700;
}

.color-option i {
    font-size: 2rem;
    margin-bottom: 4px;
}

.color-option.selected {
    border-color: var(--primary);
    border-bottom-color: var(--primary-hover);
    background-color: rgba(88, 204, 2, 0.05);
    color: var(--primary);
}

/* Stats dashboard */
.stats-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
    margin-bottom: 16px;
}

.stat-box {
    background: #ffffff;
    border: 2px solid var(--border);
    border-bottom: 5px solid var(--border);
    border-radius: 16px;
    padding: 14px;
    text-align: center;
}

.stat-box .value {
    font-family: var(--font-title);
    font-size: 1.7rem;
    font-weight: 800;
    color: var(--primary);
    margin-bottom: 2px;
}

.stat-box .label {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-weight: 700;
}

.chart-container {
    position: relative;
    height: 180px;
    width: 100%;
}

/* Achievements */
.badge-tabs {
    display: flex;
    border-bottom: 2px solid var(--border);
    margin-bottom: 16px;
}

.badge-tab {
    flex: 1;
    text-align: center;
    padding: 12px 0;
    cursor: pointer;
    font-weight: 800;
    font-size: 0.9rem;
    color: var(--text-muted);
    border-bottom: 3px solid transparent;
    transition: var(--transition);
}

.badge-tab.active {
    color: var(--primary);
    border-bottom-color: var(--primary);
}

.badge-search {
    width: 100%;
    background-color: #ffffff;
    border: 2px solid var(--border);
    border-radius: 14px;
    padding: 12px 16px;
    color: var(--text-main);
    font-family: var(--font-sans);
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 16px;
    outline: none;
}

.badge-search:focus {
    border-color: var(--primary);
}

.badges-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
    max-height: 380px;
    overflow-y: auto;
    padding-right: 4px;
    padding-bottom: 10px;
}

.badge-card {
    background: #ffffff;
    border: 2px solid var(--border);
    border-bottom: 4px solid var(--border);
    border-radius: 16px;
    padding: 12px 6px;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    transition: var(--transition);
    cursor: pointer;
}

.badge-card.locked {
    filter: grayscale(100%);
    opacity: 0.5;
}

.badge-card.unlocked {
    background: radial-gradient(circle at top, rgba(88, 204, 2, 0.08) 0%, #ffffff 100%);
    border-color: rgba(88, 204, 2, 0.3);
    border-bottom-color: rgba(88, 204, 2, 0.5);
}

.badge-card.unlocked:hover {
    transform: translateY(-2px);
    border-color: var(--primary);
    border-bottom-width: 5px;
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.05);
}

.badge-icon {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: #f1f5f9;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
    margin-bottom: 6px;
    border: 2px solid #e2e8f0;
}

.unlocked .badge-icon {
    background: rgba(88, 204, 2, 0.15);
    border-color: var(--primary);
    color: var(--primary);
}

/* Rarity classes for unlocked badges */
.badge-card.epic.unlocked {
    border-color: rgba(168, 85, 247, 0.4);
    background: radial-gradient(circle at top, rgba(168, 85, 247, 0.12) 0%, #ffffff 100%);
}
.badge-card.epic .badge-icon {
    border-color: rgb(168, 85, 247);
    color: rgb(168, 85, 247);
}

.badge-card.legendary.unlocked {
    border-color: rgba(245, 158, 11, 0.4);
    background: radial-gradient(circle at top, rgba(245, 158, 11, 0.15) 0%, #ffffff 100%);
}
.badge-card.legendary .badge-icon {
    border-color: rgb(245, 158, 11);
    color: rgb(245, 158, 11);
}

.badge-name {
    font-size: 0.75rem;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 2px;
    word-break: break-word;
}

.badge-desc {
    font-size: 0.6rem;
    color: var(--text-muted);
    line-height: 1.25;
}

/* Custom Overlays (Duolingo Style White Cards with Blurred Blue Backgrounds) */
.overlay-modal {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(224, 242, 254, 0.85); /* Cheerful blue tint */
    backdrop-filter: blur(8px);
    z-index: 100;
    display: none;
    align-items: center;
    justify-content: center;
    padding: 24px;
    animation: fadeIn 0.2s ease;
}

.overlay-content {
    background: #ffffff;
    border: 2px solid var(--border);
    border-bottom: 8px solid var(--border);
    border-radius: 24px;
    padding: 28px;
    width: 100%;
    text-align: center;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.06);
    animation: slideUp 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.overlay-logo {
    font-size: 3.8rem;
    margin-bottom: 12px;
}

.overlay-title {
    font-size: 1.7rem;
    font-weight: 800;
    margin-bottom: 8px;
    color: var(--text-main);
}

.overlay-text {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 20px;
    line-height: 1.45;
}

.game-over-stats {
    display: flex;
    justify-content: space-around;
    background: #f8fafc;
    border: 2px solid var(--border);
    border-radius: 16px;
    padding: 12px;
    margin-bottom: 20px;
}

.game-over-stat {
    text-align: center;
}

.game-over-stat .label {
    font-size: 0.7rem;
    color: var(--text-muted);
    font-weight: 700;
}

.game-over-stat .value {
    font-size: 1.1rem;
    font-weight: 800;
    color: var(--primary);
}

/* Matchmaker Interactive Layout */
.matchmaker-container {
    display: flex;
    flex-direction: column;
    gap: 16px;
    margin-top: 10px;
}



/* Category Filter Pills */
.opponent-filters {
    display: flex;
    gap: 8px;
    overflow-x: auto;
    padding-bottom: 8px;
    margin-bottom: 12px;
    white-space: nowrap;
    scrollbar-width: none;
}
.opponent-filters::-webkit-scrollbar {
    display: none;
}

.filter-pill {
    background: #e2e8f0;
    color: var(--text-muted);
    border: none;
    border-radius: 12px;
    padding: 8px 14px;
    font-weight: 700;
    font-size: 0.8rem;
    cursor: pointer;
    transition: var(--transition);
}

.filter-pill.active {
    background: var(--primary);
    color: #ffffff;
}

/* Opponent Grid */
.opponent-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(110px, 1fr));
    gap: 10px;
    max-height: 400px;
    overflow-y: auto;
    padding-right: 4px;
}

.opponent-card {
    background: #ffffff;
    border: 2px solid var(--border);
    border-bottom-width: 4px;
    border-radius: 16px;
    padding: 12px;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
}

.opponent-card:hover {
    border-color: var(--primary);
    transform: translateY(-2px);
}

.opponent-card.selected {
    border-color: var(--primary);
    background-color: rgba(88, 204, 2, 0.05);
}

.opponent-card-avatar {
    width: 48px;
    height: 48px;
    border-radius: 10px;
    border: 2px solid var(--border);
    background: #f1f5f9;
}

.opponent-card-name {
    font-weight: 800;
    font-size: 0.75rem;
    color: var(--text-main);
    line-height: 1.2;
}

.opponent-card-elo {
    font-size: 0.7rem;
    font-weight: 700;
    color: var(--primary);
}

/* Preview Pane */
.opponent-preview {
    background: #ffffff;
    border: 2px solid var(--border);
    border-bottom-width: 4px;
    border-radius: 20px;
    padding: 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 14px;
    text-align: center;
}

.opponent-preview-avatar {
    width: 80px;
    height: 80px;
    border-radius: 16px;
    border: 3px solid var(--border);
    background: #f1f5f9;
}

.opponent-preview-name {
    font-weight: 800;
    font-size: 1.2rem;
    margin: 0;
    color: var(--text-main);
}

.opponent-preview-elo {
    background: rgba(88, 204, 2, 0.1);
    color: var(--primary);
    font-weight: 800;
    font-size: 0.8rem;
    padding: 4px 10px;
    border-radius: 8px;
    margin-top: 4px;
    display: inline-block;
}

.opponent-preview-desc {
    font-size: 0.8rem;
    color: var(--text-muted);
    line-height: 1.4;
    margin: 4px 0;
}

/* Style attributes badges */
.opponent-attrs {
    display: flex;
    gap: 10px;
    width: 100%;
    justify-content: center;
    margin: 4px 0;
}

.opponent-attr-badge {
    background: #f1f5f9;
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 6px 10px;
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--text-muted);
    display: flex;
    align-items: center;
    gap: 6px;
}

/* Head-to-Head visual in Preview */
.preview-h2h-box {
    width: 100%;
    background: #f8fafc;
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 10px 14px;
    text-align: left;
}

.preview-h2h-title {
    font-size: 0.75rem;
    font-weight: 800;
    color: var(--text-muted);
    text-transform: uppercase;
    margin-bottom: 6px;
}

.preview-h2h-record {
    font-weight: 800;
    font-size: 0.85rem;
    color: var(--text-main);
    display: block;
    margin-bottom: 6px;
}

/* Turn indicators */
.turn-indicator {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background-color: transparent;
    transition: var(--transition);
}

.turn-indicator.active {
    background-color: var(--success);
    box-shadow: 0 0 8px var(--success);
    animation: pulseGlow 1.5s infinite ease-in-out;
}

.turn-indicator.thinking {
    background-color: var(--warning);
    box-shadow: 0 0 8px var(--warning);
    animation: pulseGlow 1.5s infinite ease-in-out;
}

@keyframes pulseGlow {
    0%, 100% { opacity: 0.6; transform: scale(1); }
    50% { opacity: 1; transform: scale(1.2); }
}

/* Board animations for Trainer feedback */
@keyframes shake {
  0%, 100% { transform: translateX(0); }
  10%, 30%, 50%, 70%, 90% { transform: translateX(-6px); }
  20%, 40%, 60%, 80% { transform: translateX(6px); }
}
.shake-anim {
  animation: shake 0.4s ease-in-out;
}

@keyframes greenFlash {
  0%, 100% { box-shadow: 0 0 0 rgba(88, 204, 2, 0); }
  50% { box-shadow: 0 0 24px rgba(88, 204, 2, 0.7); }
}
.flash-green-anim {
  animation: greenFlash 0.6s ease-in-out;
}

/* Last move square highlight */
.last-move-highlight {
    box-shadow: inset 0 0 0 3px rgba(251, 191, 36, 0.65) !important;
}