:root,
        [data-bs-theme="dark"] {
            --bg: #0f172a;
            --stage-bg: #020617;
            --panel: rgba(30, 41, 59, .6);
            --panel-solid: #1e293b;
            --panel-strong: rgba(30, 41, 59, .85);
            --border: #334155;
            --border-soft: rgba(51, 65, 85, .6);
            --input-bg: #0f172a;
            --text: #f1f5f9;
            --text-muted: #94a3b8;
            --text-faint: #64748b;
            --grid-line: rgba(255, 255, 255, 0.05);
        }

        [data-bs-theme="light"] {
            --bg: #f1f5f9;
            --stage-bg: #ffffff;
            --panel: rgba(255, 255, 255, .75);
            --panel-solid: #ffffff;
            --panel-strong: rgba(255, 255, 255, .9);
            --border: #e2e8f0;
            --border-soft: #e2e8f0;
            --input-bg: #ffffff;
            --text: #0f172a;
            --text-muted: #64748b;
            --text-faint: #94a3b8;
            --grid-line: rgba(0, 0, 0, 0.045);
        }

        * {
            user-select: none;
        }

        html {
            scroll-behavior: smooth;
        }

        #toolSection,
        #aboutSection,
        #whySection,
        #whoSection,
        #featuresSection {
            scroll-margin-top: 80px;
        }

        body {
            font-family: "DM Sans", sans-serif;;
            background: var(--bg);
            color: var(--text);
            min-height: 100vh;
        }

        ::-webkit-scrollbar {
            width: 6px;
            height: 6px;
        }

        ::-webkit-scrollbar-track {
            background: transparent;
        }

        ::-webkit-scrollbar-thumb {
            background: rgba(148, 163, 184, .4);
            border-radius: 999px;
        }

        ::-webkit-scrollbar-thumb:hover {
            background: rgba(148, 163, 184, .7);
        }

        .glass {
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
        }

        .panel {
            background: var(--panel-solid);
            border: 1px solid var(--border);
        }

        .panel-soft {
            background: var(--panel);
            border: 1px solid var(--border-soft);
        }

        .text-muted-c {
            color: var(--text-muted) !important;
        }

        .text-faint-c {
            color: var(--text-faint) !important;
        }

        .border-c {
            border-color: var(--border) !important;
        }

        .brand-icon {
            background: linear-gradient(135deg, #2563eb, #6366f1);
            color: #fff;
            box-shadow: 0 10px 20px -8px rgba(59, 130, 246, .5);
        }

        .brand-title {
            background: linear-gradient(90deg, #60a5fa, #a5b4fc);
            -webkit-background-clip: text;
            background-clip: text;
            color: transparent;
            font-weight: 700;
        }

        .btn-gradient {
            background: linear-gradient(90deg, #2563eb, #4f46e5);
            color: #fff;
            border: none;
        }

        .btn-gradient:hover {
            background: linear-gradient(90deg, #3b82f6, #6366f1);
            color: #fff;
        }

        /* About / Why / Who / Features section */
        .about-eyebrow {
            display: inline-flex;
            align-items: center;
            gap: .4rem;
            padding: .35rem .9rem;
            border-radius: 999px;
            background: rgba(99, 102, 241, .12);
            border: 1px solid rgba(99, 102, 241, .35);
            color: #93c5fd;
            font-size: .72rem;
            font-weight: 700;
            letter-spacing: .04em;
            text-transform: uppercase;
        }

        .info-card {
            background: var(--panel);
            border: 1px solid var(--border-soft);
            border-radius: 1rem;
            padding: 1.4rem;
            height: 100%;
            transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
        }

        .info-card:hover {
            transform: translateY(-4px);
            border-color: rgba(99, 102, 241, .5);
            box-shadow: 0 16px 30px -18px rgba(37, 99, 235, .55);
        }

        .info-icon {
            width: 46px;
            height: 46px;
            border-radius: .85rem;
            display: flex;
            align-items: center;
            justify-content: center;
            flex-shrink: 0;
            background: linear-gradient(135deg, #2563eb, #6366f1);
            color: #fff;
            font-size: 1.05rem;
            box-shadow: 0 10px 18px -8px rgba(59, 130, 246, .5);
        }

        .persona-card {
            background: var(--panel);
            border: 1px solid var(--border-soft);
            border-radius: .9rem;
            padding: 1rem .9rem;
            text-align: center;
            height: 100%;
            transition: transform .2s ease, border-color .2s ease, background .2s ease;
        }

        .persona-card:hover {
            transform: translateY(-3px);
            border-color: rgba(99, 102, 241, .5);
            background: rgba(99, 102, 241, .08);
        }

        .persona-icon {
            width: 42px;
            height: 42px;
            margin: 0 auto .6rem;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            background: rgba(99, 102, 241, .12);
            border: 1px solid rgba(99, 102, 241, .3);
            color: #a5b4fc;
            font-size: 1rem;
        }

        .feature-row-icon {
            width: 38px;
            height: 38px;
            border-radius: .65rem;
            display: flex;
            align-items: center;
            justify-content: center;
            flex-shrink: 0;
            background: rgba(37, 99, 235, .14);
            color: #60a5fa;
            font-size: .95rem;
        }

        @media (max-width: 575.98px) {
            .info-card {
                padding: 1.1rem;
            }
        }

        /* Footer */
        .site-footer {
            background: var(--panel-solid);
            border-top: 1px solid var(--border);
        }

        .footer-link {
            color: var(--text-muted);
            text-decoration: none;
            font-size: .85rem;
            transition: color .15s ease;
        }

        .footer-link:hover {
            color: #93c5fd;
        }

        .footer-heading {
            font-size: .72rem;
            font-weight: 700;
            letter-spacing: .05em;
            text-transform: uppercase;
            color: var(--text-faint);
        }

        .footer-social-btn {
            width: 36px;
            height: 36px;
            border-radius: .65rem;
            display: flex;
            align-items: center;
            justify-content: center;
            background: var(--panel);
            border: 1px solid var(--border-soft);
            color: var(--text-muted);
            transition: all .15s ease;
        }

        .footer-social-btn:hover {
            color: #fff;
            background: linear-gradient(135deg, #2563eb, #6366f1);
            border-color: transparent;
            transform: translateY(-2px);
        }

        /* Segmented control (units, tabs) */
        .seg {
            background: var(--panel-solid);
            border: 1px solid var(--border);
            border-radius: .6rem;
            padding: .25rem;
            display: flex;
            gap: .15rem;
        }

        .seg-btn {
            border: none;
            background: transparent;
            color: var(--text-muted);
            font-size: .75rem;
            font-weight: 600;
            padding: .4rem .8rem;
            border-radius: .4rem;
            flex: 1;
            text-align: center;
            transition: background .15s ease, color .15s ease;
        }

        .seg-btn.active {
            background: #2563eb;
            color: #fff;
            box-shadow: 0 2px 6px rgba(37, 99, 235, .4);
        }

        .seg-btn:not(.active):hover {
            color: var(--text);
        }

        /* Gender picker */
        .gender-btn {
            border: 1px solid var(--border);
            background: var(--input-bg);
            color: var(--text-muted);
            border-radius: .6rem;
            padding: .5rem;
            font-size: .72rem;
            font-weight: 600;
            text-align: center;
        }

        .gender-btn i {
            display: block;
            font-size: 1.05rem;
            margin-bottom: .25rem;
        }

        .gender-btn.active {
            border-color: #3b82f6;
            background: rgba(59, 130, 246, .12);
            color: var(--text);
        }

        .form-control,
        .form-select {
            background: var(--input-bg);
            border: 1px solid var(--border);
            color: var(--text);
        }

        .form-control:focus,
        .form-select:focus {
            background: var(--input-bg);
            color: var(--text);
            border-color: #3b82f6;
            box-shadow: 0 0 0 .2rem rgba(59, 130, 246, .25);
        }

        .form-control-color {
            padding: .25rem;
            height: 2rem;
        }

        /* Predefined color swatch picker */
        .color-picker-group {
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            gap: .5rem;
        }

        .color-swatch {
            width: 1.7rem;
            height: 1.7rem;
            border-radius: 50%;
            padding: 0;
            border: 2px solid transparent;
            box-shadow: 0 0 0 1px var(--border-soft);
            cursor: pointer;
            flex-shrink: 0;
            transition: transform .12s ease, box-shadow .15s ease;
        }

        .color-swatch:hover {
            transform: scale(1.1);
        }

        .color-swatch.active {
            border-color: var(--stage-bg);
            box-shadow: 0 0 0 2px #3b82f6;
        }

        .color-swatch-custom {
            width: 1.7rem;
            height: 1.7rem;
            border-radius: 50%;
            padding: 0;
            border: 2px solid transparent;
            box-shadow: 0 0 0 1px var(--border-soft);
            cursor: pointer;
            flex-shrink: 0;
            background: var(--input-bg);
            overflow: hidden;
        }

        .color-swatch-custom::-webkit-color-swatch-wrapper {
            padding: 0;
        }

        .color-swatch-custom::-webkit-color-swatch {
            border: none;
            border-radius: 50%;
        }

        .color-swatch-custom::-moz-color-swatch {
            border: none;
            border-radius: 50%;
        }

        .color-swatch-custom.ring-active {
            border-color: var(--stage-bg);
            box-shadow: 0 0 0 2px #3b82f6;
        }

        .color-group-label {
            font-size: .62rem;
            color: var(--text-muted);
            font-weight: 600;
            margin-bottom: .35rem;
        }

        ::placeholder {
            color: var(--text-faint);
            opacity: 1;
        }

        .entity-card {
            background: var(--panel);
            border: 1px solid var(--border-soft);
            border-radius: .9rem;
            padding: .65rem .75rem;
            transition: border-color .15s ease;
        }

        .entity-card:hover {
            border-color: var(--border);
        }

        .entity-swatch {
            width: 2rem;
            height: 2rem;
            border-radius: .6rem;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: .85rem;
            flex-shrink: 0;
        }

        .preset-btn {
            width: 100%;
            text-align: left;
            background: var(--panel);
            border: 1px solid var(--border-soft);
            border-radius: .8rem;
            padding: .6rem .7rem;
            display: flex;
            align-items: center;
            justify-content: space-between;
            color: var(--text);
            transition: border-color .15s ease, background .15s ease;
        }

        .preset-btn:hover {
            background: var(--panel-strong);
            border-color: #3b82f680;
        }

        .preset-icon {
            width: 1.9rem;
            height: 1.9rem;
            border-radius: .5rem;
            background: rgba(100, 116, 139, .15);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: .75rem;
            color: #60a5fa;
        }

        .canvas-grid {
            background-image: linear-gradient(to right, var(--grid-line) 1px, transparent 1px),
                linear-gradient(to bottom, var(--grid-line) 1px, transparent 1px);
            background-size: 20px 20px;
        }

        .stage-wrap {
            background: var(--stage-bg);
            border: 1px solid var(--border);
            border-radius: 1rem;
            overflow: hidden;
            min-height: 480px;
        }

        .stage-footer {
            background: var(--panel-solid);
            border-top: 1px solid var(--border);
            font-size: .7rem;
            color: var(--text-muted);
        }

        .figure-group {
            cursor: grab;
            transition: transform .1s ease-out;
        }

        .figure-group:active {
            cursor: grabbing;
        }

        .table-matrix {
            color: var(--text);
            font-size: .75rem;
        }

        .table-matrix th,
        .table-matrix td {
            border-color: var(--border-soft) !important;
        }

        .btn-icon {
            background: var(--panel-solid);
            border: 1px solid var(--border);
            color: var(--text-muted);
        }

        .btn-icon:hover {
            color: var(--text);
            background: var(--panel-strong);
        }

        .empty-box {
            border: 2px dashed var(--border);
            border-radius: 1rem;
            text-align: center;
            padding: 2.5rem 1rem;
        }

        @media (max-width: 991px) {
            .stage-wrap {
                min-height: 360px;
            }
        }