:root {
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-card: #1e293b;
    --bg-card-hover: #334155;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --border-color: #334155;
    --accent-color: #6366f1;
    --accent-hover: #4f46e5;
    --accent-gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    --danger-color: #ef4444;
    --danger-hover: #dc2626;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.3), 0 2px 4px -1px rgba(0, 0, 0, 0.2);
    --shadow-lg: 0 10px 25px -5px rgba(0, 0, 0, 0.5);
    --font-family: 'Segoe UI', system-ui, -apple-system, BlinkMacSystemFont, Roboto, sans-serif;
}

[data-theme="light"] {
    --bg-primary: #f1f5f9;
    --bg-secondary: #ffffff;
    --bg-card: #ffffff;
    --bg-card-hover: #f8fafc;
    --text-main: #0f172a;
    --text-muted: #64748b;
    --border-color: #e2e8f0;
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -1px rgba(0, 0, 0, 0.04);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-family);
    background-color: var(--bg-primary);
    color: var(--text-main);
    line-height: 1.5;
    min-height: 100vh;
    overflow-x: hidden;
}

.app-container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Header Styling */
.app-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.75rem 1.5rem;
    background-color: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
    z-index: 10;
}

.header-brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.brand-icon {
    font-size: 1.5rem;
    color: var(--warning-color);
}

.header-brand h1 {
    font-size: 1.25rem;
    font-weight: 700;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.game-tabs {
    display: flex;
    gap: 0.5rem;
    background-color: var(--bg-primary);
    padding: 0.25rem;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
}

.tab-btn {
    padding: 0.5rem 1.25rem;
    border: none;
    border-radius: var(--radius-sm);
    background: transparent;
    color: var(--text-muted);
    font-weight: 600;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.tab-btn:hover {
    color: var(--text-main);
}

.tab-btn.active {
    background: var(--accent-gradient);
    color: #ffffff;
    box-shadow: var(--shadow-sm);
}

.header-actions {
    display: flex;
    gap: 0.5rem;
}

.icon-btn {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-main);
    width: 38px;
    height: 38px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s;
}

.icon-btn:hover {
    background-color: var(--border-color);
}

.icon-btn.btn-sm {
    width: 32px;
    height: 32px;
}

/* Main Body Layout */
.app-body {
    display: grid;
    grid-template-columns: 300px 1fr 280px;
    gap: 1.25rem;
    padding: 1.25rem;
    flex: 1;
}

@media (max-width: 1200px) {
    .app-body {
        grid-template-columns: 280px 1fr;
    }
    .right-sidebar {
        grid-column: span 2;
    }
}

@media (max-width: 850px) {
    .app-body {
        grid-template-columns: 1fr;
    }
    .right-sidebar {
        grid-column: span 1;
    }
    .app-header {
        flex-direction: column;
        gap: 0.75rem;
    }
}

/* Sidebar & Panels */
.sidebar {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.panel {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1rem;
    box-shadow: var(--shadow-md);
}

.panel-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 0.75rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--border-color);
}

.panel-header h2 {
    font-size: 1rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.badge {
    background-color: var(--accent-color);
    color: white;
    font-size: 0.75rem;
    padding: 0.15rem 0.5rem;
    border-radius: 20px;
}

#names-input {
    width: 100%;
    background-color: var(--bg-primary);
    color: var(--text-main);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    padding: 0.75rem;
    font-family: inherit;
    font-size: 0.9rem;
    resize: vertical;
    outline: none;
    transition: border-color 0.2s;
}

#names-input:focus {
    border-color: var(--accent-color);
}

.names-actions {
    display: flex;
    gap: 0.5rem;
    margin-top: 0.75rem;
}

/* Buttons */
.btn {
    border: none;
    border-radius: var(--radius-sm);
    padding: 0.5rem 1rem;
    font-weight: 600;
    font-size: 0.875rem;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    transition: all 0.2s;
}

.btn-primary {
    background: var(--accent-gradient);
    color: white;
    box-shadow: 0 4px 14px rgba(99, 102, 241, 0.4);
}

.btn-primary:hover {
    opacity: 0.95;
    transform: translateY(-1px);
}

.btn-secondary {
    background-color: var(--border-color);
    color: var(--text-main);
}

.btn-secondary:hover {
    background-color: var(--bg-card-hover);
}

.btn-danger {
    background-color: var(--danger-color);
    color: white;
}

.btn-danger:hover {
    background-color: var(--danger-hover);
}

.btn-danger-outline {
    background: transparent;
    border: 1px solid var(--danger-color);
    color: var(--danger-color);
}

.btn-danger-outline:hover {
    background-color: var(--danger-color);
    color: white;
}

.btn-sm {
    padding: 0.35rem 0.65rem;
    font-size: 0.8rem;
    flex: 1;
}

.btn-lg {
    padding: 0.85rem 2.25rem;
    font-size: 1.1rem;
    border-radius: 30px;
}

/* Config Groups */
.config-group {
    display: flex;
    flex-direction: column;
    gap: 0.85rem;
}

.hidden {
    display: none !important;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
}

.form-group label {
    font-size: 0.85rem;
    color: var(--text-muted);
}

.form-select {
    background-color: var(--bg-primary);
    color: var(--text-main);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    padding: 0.45rem;
    outline: none;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.85rem;
    cursor: pointer;
    color: var(--text-main) !important;
}

/* Arena / Canvas Area */
.arena-section {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1rem;
    box-shadow: var(--shadow-md);
    position: relative;
}

.arena-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.arena-header h2 {
    font-size: 1.2rem;
    font-weight: 700;
}

.canvas-wrapper {
    flex: 1;
    min-height: 400px;
    width: 100%;
    position: relative;
    background-color: var(--bg-primary);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

#game-canvas {
    width: 100%;
    height: 100%;
    display: block;
}

.arena-controls {
    display: flex;
    justify-content: center;
    padding-top: 0.5rem;
}

/* Donation Card */
.donate-panel {
    background: linear-gradient(180deg, var(--bg-card) 0%, rgba(99, 102, 241, 0.05) 100%);
    border: 1px solid rgba(99, 102, 241, 0.3);
}

.donate-desc {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 0.75rem;
}

.qr-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    background: #ffffff;
    padding: 0.75rem;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
    margin-bottom: 0.75rem;
}

.donate-qr-img {
    max-width: 100%;
    height: auto;
    border-radius: 4px;
}

.qr-caption {
    margin-top: 0.5rem;
    font-size: 0.75rem;
    font-weight: 600;
    color: #1e293b;
}

.donate-details {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
    font-size: 0.8rem;
    color: var(--text-muted);
}

.detail-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.text-danger {
    color: var(--danger-color);
}

/* Modal Overlay */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.75);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 100;
    opacity: 1;
    transition: opacity 0.25s ease;
}

.modal-overlay.hidden {
    opacity: 0;
    pointer-events: none;
}

.modal-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    width: 90%;
    max-width: 480px;
    padding: 1.75rem;
    box-shadow: var(--shadow-lg);
    position: relative;
    text-align: center;
    animation: modalPop 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

@keyframes modalPop {
    0% { transform: scale(0.8); opacity: 0; }
    100% { transform: scale(1); opacity: 1; }
}

.modal-close-btn {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: transparent;
    border: none;
    font-size: 1.5rem;
    color: var(--text-muted);
    cursor: pointer;
}

.winner-trophy-icon {
    font-size: 3.5rem;
    color: var(--warning-color);
    margin-bottom: 0.5rem;
    filter: drop-shadow(0 4px 8px rgba(245, 158, 11, 0.4));
}

.modal-header h2 {
    font-size: 1.5rem;
    font-weight: 800;
}

.modal-body {
    margin: 1.25rem 0;
}

.winner-display {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--accent-color);
    word-break: break-word;
    background-color: var(--bg-primary);
    padding: 1rem;
    border-radius: var(--radius-md);
    border: 1px dashed var(--accent-color);
}

.winner-rank-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.5rem 0.75rem;
    margin-bottom: 0.35rem;
    border-radius: var(--radius-sm);
    background: var(--bg-card);
    font-size: 1rem;
}

.modal-footer {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.modal-footer .btn {
    flex: 1;
}

/* Confetti Overlay */
.confetti-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    pointer-events: none;
    z-index: 99;
}