:root {
            color-scheme: light;
        }
        * {
            box-sizing: border-box;
        }
        body {
            margin: 0;
            min-height: 100vh;
            display: flex;
            justify-content: center;
            background:
                radial-gradient(circle at top left, rgba(59, 130, 246, 0.16), transparent 60%),
                radial-gradient(circle at bottom right, rgba(139, 92, 246, 0.18), transparent 55%),
                #f4f5fb;
            color: #1f2937;
            font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
        }
        main.app {
            width: min(1200px, 94vw);
            padding: 56px 0 72px;
        }
        .hero {
            text-align: center;
            margin-bottom: 36px;
        }
        .hero h1 {
            font-size: clamp(30px, 4vw, 42px);
            margin: 0;
            color: #0f172a;
            letter-spacing: -0.02em;
        }
        .hero p {
            margin: 16px auto 0;
            max-width: 680px;
            color: #475569;
            line-height: 1.7;
            font-size: 16px;
        }
        .recent-section {
            margin-top: 36px;
            padding: 24px;
            border-radius: 22px;
            border: 1px solid rgba(226, 232, 240, 0.7);
            background: rgba(255, 255, 255, 0.82);
            box-shadow: 0 14px 34px rgba(15, 23, 42, 0.06);
        }
        .recent-section h3 {
            margin: 0;
            font-size: 18px;
            color: #0f172a;
        }
        .recent-section p {
            margin: 10px 0 18px;
            color: #64748b;
            font-size: 14px;
        }
        .recent-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
            gap: 12px;
        }
        .recent-card {
            display: block;
            border: 1px solid rgba(226, 232, 240, 0.85);
            border-radius: 16px;
            padding: 16px;
            background: linear-gradient(180deg, rgba(248, 250, 252, 0.88), rgba(255, 255, 255, 0.96));
            text-align: left;
            cursor: pointer;
            transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
            color: inherit;
            text-decoration: none;
        }
        .recent-card:hover,
        .recent-card:focus-visible {
            outline: none;
            transform: translateY(-2px);
            box-shadow: 0 16px 30px rgba(79, 70, 229, 0.14);
            border-color: rgba(99, 102, 241, 0.45);
        }
        .recent-title {
            display: block;
            font-weight: 600;
            font-size: 15px;
            color: #1f2937;
            margin-bottom: 8px;
        }
        .recent-meta {
            display: block;
            font-size: 12px;
            color: #94a3b8;
        }
        .flow-steps {
            display: flex;
            gap: 18px;
            justify-content: center;
            margin-bottom: 24px;
            flex-wrap: wrap;
        }
        .flow-step {
            display: flex;
            align-items: center;
            gap: 10px;
            padding: 10px 18px;
            border-radius: 999px;
            background: rgba(148, 163, 184, 0.12);
            color: #64748b;
            font-weight: 500;
            transition: all 0.2s ease;
        }
        .flow-step .index {
            width: 28px;
            height: 28px;
            border-radius: 50%;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            background: rgba(148, 163, 184, 0.25);
            font-size: 15px;
            font-weight: 600;
        }
        .flow-step.active {
            background: rgba(59, 130, 246, 0.14);
            color: #1d4ed8;
        }
        .flow-step.active .index {
            background: linear-gradient(135deg, #2563eb 0%, #7c3aed 100%);
            color: #fff;
        }
        .status-bar {
            margin: 0 auto 24px;
            width: min(980px, 90vw);
            padding: 14px 18px;
            border-radius: 14px;
            font-weight: 500;
            display: none;
        }
        .status-bar[data-tone="info"] {
            background: rgba(59, 130, 246, 0.12);
            color: #1d4ed8;
        }
        .status-bar[data-tone="success"] {
            background: rgba(34, 197, 94, 0.15);
            color: #047857;
        }
        .status-bar[data-tone="danger"] {
            background: rgba(248, 113, 113, 0.15);
            color: #b91c1c;
        }
        .status-bar.show {
            display: block;
        }
        .step-card {
            display: none;
            background: rgba(255, 255, 255, 0.95);
            border-radius: 24px;
            padding: 32px;
            box-shadow: 0 25px 70px rgba(15, 23, 42, 0.08);
            border: 1px solid rgba(226, 232, 240, 0.6);
            backdrop-filter: blur(10px);
            width: min(1200px, 94vw);
            margin: 0 auto 28px;
        }
        .step-card.active {
            display: block;
        }
        .requirement-form {
            display: flex;
            flex-direction: column;
            gap: 24px;
        }
        .manual-entry {
            margin-top: -6px;
            display: flex;
            align-items: center;
            gap: 12px;
            flex-wrap: wrap;
            color: #475569;
            font-size: 14px;
        }
        .manual-entry .text-link {
            color: #2563eb;
            text-decoration: none;
            font-weight: 600;
        }
        .manual-entry .text-link:hover {
            text-decoration: underline;
        }
        .input-stack {
            position: relative;
            display: flex;
            align-items: stretch;
            gap: 18px;
        }
        .rich-input {
            flex: 1;
            min-height: 220px;
            padding: 18px 22px;
            border-radius: 22px;
            border: 1px solid rgba(203, 213, 225, 0.9);
            background: rgba(248, 250, 252, 0.92);
            font-size: 16px;
            line-height: 1.7;
            transition: border 0.2s ease, box-shadow 0.2s ease;
            outline: none;
            white-space: pre-wrap;
            word-break: break-word;
            overflow: auto;
        }
        .rich-input:focus {
            border-color: #6366f1;
            box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.18);
            background: #fff;
        }
        .rich-input.is-empty::before {
            content: attr(data-placeholder);
            color: #94a3b8;
        }
        .rich-input table {
            border-collapse: collapse;
            width: 100%;
        }
        .rich-input table td,
        .rich-input table th {
            border: 1px solid rgba(148, 163, 184, 0.6);
            padding: 8px 10px;
        }
        .next-button {
            min-width: 150px;
            border-radius: 20px;
            border: none;
            cursor: pointer;
            background: linear-gradient(135deg, #2563eb 5%, #7c3aed 100%);
            color: #fff;
            font-size: 16px;
            font-weight: 600;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 10px;
            padding: 0 26px;
            transition: transform 0.2s ease, box-shadow 0.2s ease;
        }
        .next-button svg {
            width: 18px;
            height: 18px;
        }
        .next-button:hover:not([disabled]) {
            transform: translateX(4px);
            box-shadow: 0 18px 38px rgba(79, 70, 229, 0.22);
        }
        .next-button[disabled] {
            opacity: 0.6;
            cursor: not-allowed;
            box-shadow: none;
        }
        .step-header {
            display: flex;
            justify-content: space-between;
            align-items: flex-start;
            gap: 24px;
            margin-bottom: 24px;
        }
        .step-header h2 {
            margin: 0;
            font-size: 24px;
            color: #0f172a;
        }
        .step-header p {
            margin: 8px 0 0;
            color: #64748b;
        }
        .step-actions {
            display: flex;
            gap: 12px;
            flex-wrap: wrap;
        }
        .btn {
            border: none;
            border-radius: 999px;
            padding: 12px 22px;
            font-size: 15px;
            font-weight: 600;
            cursor: pointer;
            transition: transform 0.2s ease, box-shadow 0.2s ease;
        }
        .btn.primary {
            background: linear-gradient(135deg, #2563eb 0%, #6366f1 100%);
            color: #fff;
        }
        .btn.ghost {
            background: rgba(148, 163, 184, 0.15);
            color: #475569;
        }
        .btn:hover:not([disabled]) {
            transform: translateY(-1px);
            box-shadow: 0 12px 24px rgba(15, 23, 42, 0.12);
        }
        .btn[disabled] {
            opacity: 0.6;
            cursor: not-allowed;
            box-shadow: none;
        }
        .editor-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
            gap: 20px;
        }
        #markdown-editor {
            min-height: 420px;
            border-radius: 18px;
            border: 1px solid rgba(203, 213, 225, 0.75);
            background: rgba(15, 23, 42, 0.85);
            color: #f8fafc;
            font-family: "JetBrains Mono", "Fira Code", Consolas, monospace;
            font-size: 14px;
            line-height: 1.7;
            padding: 18px 20px;
            resize: vertical;
            box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.02);
        }
        #markdown-editor:focus {
            outline: none;
            border-color: rgba(99, 102, 241, 0.8);
            box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.18);
        }
        .markdown-preview {
            border-radius: 18px;
            border: 1px solid rgba(226, 232, 240, 0.7);
            background: rgba(248, 250, 252, 0.96);
            padding: 22px;
            max-height: 520px;
            overflow: auto;
            color: #1f2937;
            line-height: 1.7;
        }
        .markdown-preview h1,
        .markdown-preview h2,
        .markdown-preview h3 {
            margin-top: 1.4em;
            margin-bottom: 0.6em;
        }
        .markdown-preview p {
            margin: 0.6em 0;
        }
        .mind-editor {
            border-radius: 22px;
            border: 1px solid rgba(226, 232, 240, 0.7);
            background: linear-gradient(180deg, rgba(248, 250, 252, 0.72), rgba(255, 255, 255, 0.95));
            padding: 0;
            min-height: 420px;
            overflow: hidden;
        }
        #mind-container {
            width: 100%;
            height: 560px;
            min-height: 360px;
            border-radius: inherit;
            background: #ffffff;
            box-shadow: inset 0 0 0 1px rgba(226, 232, 240, 0.6);
            overflow: hidden;
        }
        .selection-area {
            border: 2px solid rgba(99, 102, 241, 0.8) !important;
            background: rgba(99, 102, 241, 0.12) !important;
            box-shadow: 0 10px 30px rgba(79, 70, 229, 0.18);
            border-radius: 12px;
        }
        .mindmap-toolbar {
            position: absolute;
            top: 18px;
            right: 18px;
            z-index: 5;
        }
        svg#mindmap-svg {
            width: 100%;
            height: 540px;
        }
        .loading-mask {
            position: fixed;
            inset: 0;
            display: flex;
            align-items: center;
            justify-content: center;
            background: rgba(15, 23, 42, 0.35);
            backdrop-filter: blur(6px);
            z-index: 99;
            color: #f8fafc;
            font-size: 18px;
            font-weight: 500;
            gap: 14px;
        }
        .loading-mask.hidden {
            display: none;
        }
        .spinner {
            width: 20px;
            height: 20px;
            border-radius: 50%;
            border: 3px solid rgba(255, 255, 255, 0.3);
            border-top-color: #fff;
            animation: spin 0.8s linear infinite;
        }
        @keyframes spin {
            to { transform: rotate(360deg); }
        }
        footer {
            text-align: center;
            color: #94a3b8;
            font-size: 14px;
            margin-top: 12px;
        }
        .ad-container {
            margin: 32px 0;
            padding: 20px;
            background: #ffffff;
            border-radius: 12px;
            border: 1px solid rgba(226, 232, 240, 0.6);
            text-align: center;
            min-height: 100px;
            display: flex;
            align-items: center;
            justify-content: center;
            color: #94a3b8;
            font-size: 14px;
        }
        .ad-container::before {
            content: "广告位";
            opacity: 0.5;
        }
        .breadcrumb {
            margin-bottom: 24px;
            font-size: 14px;
            color: #64748b;
        }
        .breadcrumb a {
            color: #3b82f6;
            text-decoration: none;
        }
        .breadcrumb a:hover {
            text-decoration: underline;
        }
        .breadcrumb span {
            margin: 0 8px;
            color: #cbd5e1;
        }
        .mode-switch {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
            gap: 12px;
            margin: 12px 0 16px;
        }
        .mode-option {
            border: 1px solid #e2e8f0;
            border-radius: 12px;
            padding: 12px 14px;
            display: flex;
            gap: 10px;
            align-items: flex-start;
            background: #fff;
            cursor: pointer;
            transition: border-color 0.16s ease, box-shadow 0.16s ease;
        }
        .mode-option input {
            margin-top: 4px;
        }
        .mode-option strong {
            display: block;
            color: #0f172a;
        }
        .mode-option span {
            display: block;
            color: #64748b;
            font-size: 13px;
            line-height: 1.5;
        }
        .mode-option.active {
            border-color: #6366f1;
            box-shadow: 0 8px 18px rgba(99, 102, 241, 0.18);
        }
        /* 功能特点展示区（3D圆形轮播） */
        .features-carousel-3d {
            margin: 60px 0;
            perspective: 1500px;
            height: 400px;
            overflow: hidden;
        }
        .carousel-wrapper {
            position: relative;
            width: 100%;
            height: 100%;
            display: flex;
            align-items: center;
            justify-content: center;
        }
        .carousel-stage {
            position: relative;
            width: 300px;
            height: 300px;
            transform-style: preserve-3d;
            transition: transform 0.5s ease-out;
            cursor: grab;
            user-select: none;
            -webkit-user-select: none;
            -moz-user-select: none;
            -ms-user-select: none;
        }
        .carousel-stage:active {
            cursor: grabbing;
        }
        .carousel-stage * {
            user-select: none;
            -webkit-user-select: none;
            -moz-user-select: none;
            -ms-user-select: none;
        }
        .carousel-stage .feature-card {
            position: absolute;
            width: 260px;
            height: 320px;
            left: 50%;
            top: 50%;
            margin-left: -130px;
            margin-top: -160px;
            background: rgba(255, 255, 255, 0.95);
            border: 1px solid rgba(226, 232, 240, 0.8);
            border-radius: 20px;
            padding: 32px 24px;
            text-align: center;
            box-shadow: 0 10px 40px rgba(15, 23, 42, 0.15);
            backdrop-filter: blur(10px);
            transition: box-shadow 0.3s ease, opacity 0.3s ease;
        }
        .carousel-stage .feature-card:hover {
            box-shadow: 0 20px 60px rgba(15, 23, 42, 0.25);
        }
        .carousel-stage .feature-icon {
            width: 64px;
            height: 64px;
            margin: 0 auto 20px;
            border-radius: 18px;
            display: flex;
            align-items: center;
            justify-content: center;
            color: #fff;
        }
        .carousel-stage .feature-icon svg {
            width: 32px;
            height: 32px;
        }
        .carousel-stage .feature-card h3 {
            margin: 0 0 12px;
            font-size: 18px;
            color: #0f172a;
            font-weight: 700;
        }
        .carousel-stage .feature-card p {
            margin: 0;
            font-size: 14px;
            color: #64748b;
            line-height: 1.7;
        }

        /* 3D等距流程图 */
        .isometric-flow-section {
            margin: 60px 0 40px;
            padding: 40px 32px 32px;
            background: linear-gradient(180deg, rgba(248, 250, 252, 0.5), rgba(255, 255, 255, 0.8));
            border-radius: 32px;
        }
        .isometric-container {
            max-width: 1200px;
            margin: 24px auto 0;
            background: #fff;
            border-radius: 24px;
            padding: 30px 20px 20px;
            box-shadow: 0 10px 40px rgba(15, 23, 42, 0.08);
        }
        .isometric-canvas {
            width: 100%;
            height: auto;
            display: block;
        }
        .iso-module {
            cursor: pointer;
            transition: all 0.3s ease;
        }
        .iso-module:hover {
            filter: brightness(1.1);
            transform: translateY(-2px);
        }
        .iso-module.active {
            animation: moduleGlow 2s infinite;
        }
        @keyframes moduleGlow {
            0%, 100% {
                filter: drop-shadow(0 0 10px rgba(99, 102, 241, 0.3));
            }
            50% {
                filter: drop-shadow(0 0 20px rgba(99, 102, 241, 0.6));
            }
        }
        .pipe {
            transition: stroke 0.3s ease;
        }
        .flow-particle {
            fill: #6366f1;
            filter: drop-shadow(0 0 6px rgba(99, 102, 241, 0.8));
        }
        .iso-module-future {
            cursor: default;
            transition: all 0.3s ease;
        }
        .iso-module-future:hover {
            opacity: 0.8 !important;
        }
        .pipe-future {
            animation: dashFlow 20s linear infinite;
        }
        @keyframes dashFlow {
            to {
                stroke-dashoffset: -100;
            }
        }

        /* 使用场景展示区 */
        .scenarios-section {
            margin: 48px 0 40px;
            padding: 40px 32px;
            background: rgba(255, 255, 255, 0.85);
            border-radius: 24px;
            border: 1px solid rgba(226, 232, 240, 0.6);
            box-shadow: 0 14px 34px rgba(15, 23, 42, 0.06);
        }
        .section-title {
            text-align: center;
            font-size: 28px;
            margin: 0 0 12px;
            color: #0f172a;
            font-weight: 700;
        }
        .section-subtitle {
            text-align: center;
            color: #64748b;
            font-size: 15px;
            margin: 0 auto 32px;
            max-width: 600px;
        }
        .scenarios-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 20px;
        }
        .scenario-card {
            background: linear-gradient(180deg, rgba(248, 250, 252, 0.9), rgba(255, 255, 255, 0.98));
            border: 1px solid rgba(226, 232, 240, 0.8);
            border-radius: 18px;
            padding: 24px;
            transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
        }
        .scenario-card:hover {
            transform: translateY(-3px);
            box-shadow: 0 16px 32px rgba(15, 23, 42, 0.08);
            border-color: rgba(99, 102, 241, 0.3);
        }
        .scenario-icon {
            font-size: 40px;
            margin-bottom: 16px;
            display: block;
        }
        .scenario-card h3 {
            margin: 0 0 12px;
            font-size: 18px;
            color: #0f172a;
            font-weight: 600;
        }
        .scenario-card p {
            margin: 0 0 16px;
            font-size: 14px;
            color: #64748b;
            line-height: 1.6;
        }
        .scenario-tags {
            display: flex;
            gap: 8px;
            flex-wrap: wrap;
        }
        .scenario-tags .tag {
            display: inline-block;
            padding: 4px 12px;
            background: rgba(99, 102, 241, 0.1);
            color: #6366f1;
            border-radius: 999px;
            font-size: 12px;
            font-weight: 500;
        }

        /* 优化后的案例卡片 */
        .recent-card-header {
            display: flex;
            align-items: center;
            gap: 10px;
            margin-bottom: 4px;
        }
        .recent-icon {
            width: 36px;
            height: 36px;
            border-radius: 10px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 18px;
            flex-shrink: 0;
        }
        .recent-category {
            display: inline-block;
            padding: 4px 10px;
            border-radius: 999px;
            font-size: 11px;
            font-weight: 600;
            letter-spacing: 0.3px;
        }

        @media (max-width: 720px) {
            .input-stack {
                flex-direction: column;
            }
            .next-button {
                padding: 14px 22px;
            }
            .step-header {
                flex-direction: column;
                align-items: flex-start;
            }
            .step-actions {
                width: 100%;
            }
            .btn {
                flex: 1;
                justify-content: center;
            }
            .features-grid {
                grid-template-columns: 1fr;
            }
            .scenarios-grid {
                grid-template-columns: 1fr;
            }
            .scenarios-section {
                padding: 28px 20px;
            }
            .section-title {
                font-size: 24px;
            }
        }