:root {
            /* RPG Blacksmith Theme Colors */
            --bg-color: #120e0a;
            --container-bg: #241c14;
            --border-color: #5c4033; /* Dark Brown/Bronze */
            --border-light: #8b6508; /* Gold/Brass highlight */
            --text-main: #d4c4a8; /* Parchment */
            --text-muted: #8a7b66;
            --key-color: #ffb732; /* Glowing ember */
            --btn-bg: linear-gradient(to bottom, #4a3219, #2a1c0d);
            --btn-hover: linear-gradient(to bottom, #5c4033, #3a2818);
            --btn-active: linear-gradient(to bottom, #2a1c0d, #4a3219);
            --danger-bg: linear-gradient(to bottom, #8b0000, #5c0000);
            --input-bg: #0a0806;
            
            /* Spacing & Typography */
            --spacing-sm: clamp(0.5rem, 1.5vw, 0.75rem);
            --spacing-md: clamp(1rem, 3vw, 1.5rem);
            --spacing-lg: clamp(1.5rem, 4vw, 2rem);
            --font-title: 'Palatino Linotype', 'Book Antiqua', Palatino, serif;
            --font-body: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            --font-mono: 'Courier New', Courier, monospace;
            
            /* Safe Areas */
            --safe-top: env(safe-area-inset-top, 0px);
            --safe-bottom: env(safe-area-inset-bottom, 0px);
        }

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

        body {
            font-family: var(--font-body);
            background-color: var(--bg-color);
            background-image: radial-gradient(circle at center, #2a1c0d 0%, #120e0a 100%);
            color: var(--text-main);
            display: flex;
            align-items: center;
            justify-content: center;
            min-height: 100vh;
            padding: calc(var(--safe-top) + var(--spacing-md)) var(--spacing-md) calc(var(--safe-bottom) + var(--spacing-md));
            
            /* Mandatory constraints */
            -webkit-user-select: none;
            -moz-user-select: none;
            -ms-user-select: none;
            user-select: none;
            -webkit-touch-callout: none;
        }

        .forge-container {
            width: min(100%, 600px);
            background-color: var(--container-bg);
            border: 3px solid var(--border-color);
            border-radius: 12px;
            box-shadow: 0 0 20px rgba(0,0,0,0.8), inset 0 0 15px rgba(0,0,0,0.5);
            padding: var(--spacing-lg);
            display: flex;
            flex-direction: column;
            gap: var(--spacing-md);
            position: relative;
            overflow: hidden;
        }

        /* Decorative corners */
        .forge-container::before, .forge-container::after {
            content: '';
            position: absolute;
            width: 20px;
            height: 20px;
            border: 2px solid var(--border-light);
            border-radius: 50%;
            background: var(--bg-color);
        }
        .forge-container::before { top: 10px; left: 10px; }
        .forge-container::after { top: 10px; right: 10px; }

        .header {
            text-align: center;
            border-bottom: 2px solid var(--border-color);
            padding-bottom: var(--spacing-md);
            margin-bottom: var(--spacing-sm);
        }

        h1 {
            font-family: var(--font-title);
            font-size: clamp(1.8rem, 6vw, 2.5rem);
            color: var(--border-light);
            text-shadow: 2px 2px 4px rgba(0,0,0,0.8);
            letter-spacing: 2px;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 10px;
        }

        .input-group {
            display: flex;
            flex-direction: column;
            gap: 5px;
        }

        label {
            font-family: var(--font-title);
            font-size: 0.9rem;
            color: var(--text-muted);
            text-transform: uppercase;
            letter-spacing: 1px;
        }

        input[type="text"], select {
            width: 100%;
            background-color: var(--input-bg);
            border: 2px solid var(--border-color);
            color: var(--text-main);
            padding: 12px;
            font-size: 1rem;
            border-radius: 6px;
            font-family: var(--font-mono);
            outline: none;
            box-shadow: inset 0 2px 5px rgba(0,0,0,0.8);
            transition: border-color 0.3s;
            /* Allow text selection in inputs */
            -webkit-user-select: text;
            -moz-user-select: text;
            -ms-user-select: text;
            user-select: text;
        }

        input[type="text"]:focus, select:focus {
            border-color: var(--border-light);
        }

        input[type="text"]::placeholder {
            color: #555;
            font-family: var(--font-body);
        }

        .output-wrapper {
            position: relative;
            background-color: var(--input-bg);
            border: 2px solid var(--border-light);
            border-radius: 6px;
            display: flex;
            align-items: stretch;
            box-shadow: 0 0 10px rgba(139, 101, 8, 0.2), inset 0 2px 10px rgba(0,0,0,0.9);
        }

        .key-display {
            flex-grow: 1;
            padding: 15px;
            font-family: var(--font-mono);
            font-size: clamp(0.9rem, 2.5vw, 1.1rem);
            color: var(--key-color);
            word-break: break-all;
            overflow-x: auto;
            white-space: pre-wrap;
            max-height: 120px;
            overflow-y: auto;
            text-shadow: 0 0 5px rgba(255, 183, 50, 0.3);
            
            /* Mandatory: Allow selection for copying */
            -webkit-user-select: text;
            -moz-user-select: text;
            -ms-user-select: text;
            user-select: text;
        }

        /* Custom Scrollbar for forge theme */
        .key-display::-webkit-scrollbar { width: 8px; height: 8px; }
        .key-display::-webkit-scrollbar-track { background: var(--input-bg); }
        .key-display::-webkit-scrollbar-thumb { background: var(--border-color); border-radius: 4px; }
        .key-display::-webkit-scrollbar-thumb:hover { background: var(--border-light); }

        .copy-btn {
            background: var(--btn-bg);
            border: none;
            border-left: 2px solid var(--border-color);
            color: var(--text-main);
            padding: 0 15px;
            cursor: pointer;
            font-size: 1.5rem;
            border-radius: 0 4px 4px 0;
            transition: all 0.2s;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .copy-btn:hover { background: var(--btn-hover); }
        .copy-btn:active { background: var(--btn-active); }

        .controls-row {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: var(--spacing-md);
            align-items: end;
        }

        .checkbox-group {
            display: flex;
            align-items: center;
            gap: 8px;
            height: 44px; /* Touch target size */
            cursor: pointer;
        }

        .checkbox-group input[type="checkbox"] {
            width: 20px;
            height: 20px;
            accent-color: var(--border-light);
            cursor: pointer;
        }

        .generate-btn {
            background: var(--btn-bg);
            border: 2px solid var(--border-light);
            color: var(--text-main);
            font-family: var(--font-title);
            font-size: 1.2rem;
            font-weight: bold;
            padding: 15px;
            border-radius: 8px;
            cursor: pointer;
            text-transform: uppercase;
            letter-spacing: 2px;
            box-shadow: 0 4px 6px rgba(0,0,0,0.5), inset 0 1px 0 rgba(255,255,255,0.1);
            transition: all 0.1s;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 10px;
            margin-top: var(--spacing-sm);
        }

        .generate-btn:hover {
            background: var(--btn-hover);
            box-shadow: 0 6px 8px rgba(0,0,0,0.6), inset 0 1px 0 rgba(255,255,255,0.2);
        }

        .generate-btn:active {
            background: var(--btn-active);
            transform: translateY(2px);
            box-shadow: 0 1px 2px rgba(0,0,0,0.5);
        }

        .entropy-container {
            background: var(--input-bg);
            border: 1px solid var(--border-color);
            border-radius: 4px;
            padding: 8px;
            display: flex;
            flex-direction: column;
            gap: 5px;
        }

        .entropy-header {
            display: flex;
            justify-content: space-between;
            font-size: 0.8rem;
            color: var(--text-muted);
        }

        .entropy-bar-bg {
            height: 6px;
            background: #111;
            border-radius: 3px;
            overflow: hidden;
        }

        .entropy-bar-fill {
            height: 100%;
            width: 0%;
            background: linear-gradient(90deg, #8b0000, #ffb732, #00ff00);
            transition: width 0.5s ease-out;
        }

        /* History Section */
        .history-section {
            margin-top: var(--spacing-md);
            border-top: 2px dashed var(--border-color);
            padding-top: var(--spacing-md);
        }

        .history-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 10px;
        }

        .history-header h3 {
            font-family: var(--font-title);
            font-size: 1.1rem;
            color: var(--border-light);
        }

        .clear-btn {
            background: var(--danger-bg);
            border: 1px solid #ff0000;
            color: white;
            padding: 5px 10px;
            border-radius: 4px;
            font-size: 0.8rem;
            cursor: pointer;
        }

        .history-list {
            list-style: none;
            max-height: 150px;
            overflow-y: auto;
            display: flex;
            flex-direction: column;
            gap: 8px;
            padding-right: 5px;
        }

        .history-list::-webkit-scrollbar { width: 6px; }
        .history-list::-webkit-scrollbar-track { background: var(--input-bg); }
        .history-list::-webkit-scrollbar-thumb { background: var(--border-color); border-radius: 3px; }

        .history-item {
            background: var(--input-bg);
            border: 1px solid var(--border-color);
            padding: 8px;
            border-radius: 4px;
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-size: 0.85rem;
        }

        .history-info {
            display: flex;
            flex-direction: column;
            overflow: hidden;
        }

        .history-name {
            color: var(--text-main);
            font-weight: bold;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }

        .history-date {
            color: var(--text-muted);
            font-size: 0.75rem;
        }

        .history-copy {
            background: none;
            border: none;
            color: var(--border-light);
            font-size: 1.2rem;
            cursor: pointer;
            padding: 5px;
        }

        /* Toast Notification */
        .toast {
            position: fixed;
            bottom: calc(var(--safe-bottom) + 20px);
            left: 50%;
            transform: translateX(-50%) translateY(100px);
            background: rgba(20, 15, 10, 0.95);
            border: 2px solid var(--border-light);
            color: var(--key-color);
            padding: 12px 24px;
            border-radius: 30px;
            font-family: var(--font-title);
            font-weight: bold;
            box-shadow: 0 5px 15px rgba(0,0,0,0.8);
            opacity: 0;
            transition: all 0.3s cubic-bezier(0.68, -0.55, 0.265, 1.55);
            z-index: 1000;
            pointer-events: none;
        }

        .toast.show {
            transform: translateX(-50%) translateY(0);
            opacity: 1;
        }

        /* Responsive adjustments */
        @media (max-width: 480px) {
            .controls-row {
                grid-template-columns: 1fr;
                gap: 10px;
            }
            .forge-container {
                border-width: 2px;
            }
        }