/* CSS Variables - Inherited Visual Contract */
        :root {
            --color-primary: #6a3be2;
            --color-primary-dark: #4d26b0;
            --color-primary-light: #ece5fe;
            --color-bg-dark: #0f1016;
            --color-bg-light: #f8f9fc;
            --color-surface: #ffffff;
            --color-ink-main: #1d1d1f;
            --color-ink-sub: #6e6e73;
            --color-ink-inverse: #ffffff;
            --color-ink-inverse-sub: rgba(255, 255, 255, 0.7);
            
            --radius-lg: 22px;
            --radius-md: 16px;
            --radius-sm: 8px;
            
            --shadow-sm: 0 4px 24px rgba(0, 0, 0, 0.04);
            --shadow-md: 0 12px 32px rgba(106, 59, 226, 0.1);
            --shadow-glass: 0 8px 32px rgba(0, 0, 0, 0.1);
            
            --transition: 0.35s ease;
        }

        /* Base Styles */
        body {
            font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
            color: var(--color-ink-main);
            background-color: var(--color-bg-light);
            line-height: 1.6;
            margin: 0;
            padding: 0;
            -webkit-font-smoothing: antialiased;
        }

        /* Utility & Layout Rules */
        .shell {
            display: flex;
            flex-direction: column;
            min-height: 100vh;
        }

        .binder {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 2rem;
            width: 100%;
            box-sizing: border-box;
        }

        .flex-matrix {
            display: flex;
            flex-wrap: wrap;
        }

        .flex-matrix > * {
            min-width: 0;
        }

        .prose-wrap {
            word-break: break-word;
            overflow-wrap: break-word;
            white-space: normal;
        }

        .prose-keep {
            word-break: keep-all;
            overflow-wrap: break-word;
            white-space: normal;
        }

        /* Header (Crown) - Preserved Exact Structure & Styles */
        .crown {
            position: sticky;
            top: 0;
            z-index: 100;
            background: rgba(255, 255, 255, 0.85);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            border-bottom: 1px solid rgba(0, 0, 0, 0.05);
        }

        .ribbon {
            height: 72px;
            align-items: center;
            justify-content: space-between;
        }

        .stamp img {
            height: 32px;
            display: block;
        }

        .index {
            gap: 2rem;
            align-items: center;
        }

        .xref {
            color: var(--color-ink-main);
            text-decoration: none;
            font-size: 0.95rem;
            font-weight: 500;
            transition: color var(--transition);
        }

        .xref:hover,
        .xref.active {
            color: var(--color-primary);
        }

        /* Buttons (Macro) */
        .macro {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            padding: 1rem 2.5rem;
            border-radius: 100px;
            font-weight: 600;
            text-decoration: none;
            transition: all var(--transition);
            cursor: pointer;
            border: none;
            font-size: 1rem;
            white-space: nowrap;
        }

        .ink-primary {
            background: var(--color-primary);
            color: var(--color-ink-inverse);
            box-shadow: var(--shadow-md);
        }

        .ink-primary:hover {
            background: var(--color-primary-dark);
            transform: translateY(-2px);
            box-shadow: 0 16px 40px rgba(106, 59, 226, 0.2);
        }

        /* Typography */
        .crest-mega {
            font-weight: 700;
            line-height: 1.2;
            font-size: clamp(2.5rem, 5vw, 4rem);
            letter-spacing: -0.02em;
            margin: 0 0 1.5rem 0;
        }

        .crest-major {
            font-weight: 700;
            line-height: 1.3;
            font-size: clamp(2rem, 4vw, 2.5rem);
            letter-spacing: -0.01em;
            margin: 0 0 1rem 0;
            color: var(--color-ink-main);
        }

        .crest-minor {
            font-weight: 600;
            line-height: 1.4;
            font-size: 1.25rem;
            margin: 0 0 0.5rem 0;
            color: var(--color-ink-main);
        }

        .prose-lead {
            font-size: 1.125rem;
            color: var(--color-ink-inverse-sub);
            margin: 0 0 2.5rem 0;
            line-height: 1.8;
            max-width: 90%;
        }

        .prose-body {
            font-size: 1rem;
            color: var(--color-ink-sub);
            margin: 0;
        }

        /* --- Specific Stage Styles --- */

        /* Stage 1: Intro (Hero Variant) */
        .stage-intro {
            background-color: var(--color-bg-dark);
            color: var(--color-ink-inverse);
            padding: 120px 0;
            position: relative;
            overflow: hidden;
        }

        /* Ambient background glow inherited from creative seed */
        .stage-intro::before {
            content: '';
            position: absolute;
            top: -50%;
            right: -20%;
            width: 80%;
            height: 150%;
            background: radial-gradient(ellipse at center, rgba(106,59,226,0.15) 0%, rgba(15,16,22,0) 70%);
            border-radius: 50%;
            pointer-events: none;
        }

        .easel-intro {
            align-items: center;
            gap: 4rem;
        }

        .intro-prose {
            flex: 1;
            min-width: 300px;
            z-index: 2;
        }

        .intro-plate {
            flex: 1.2;
            min-width: 300px;
            position: relative;
            z-index: 2;
        }

        /* Data UI: Sync Visualization */
        .plate-sync {
            position: relative;
            width: 100%;
            aspect-ratio: 4/3;
            background: rgba(255, 255, 255, 0.03);
            border: 1px solid rgba(255, 255, 255, 0.08);
            border-radius: var(--radius-lg);
            padding: 2rem;
            box-sizing: border-box;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .device-pc, .device-mobile {
            background: rgba(255, 255, 255, 0.05);
            border: 1px solid rgba(255, 255, 255, 0.1);
            backdrop-filter: blur(8px);
            display: flex;
            flex-direction: column;
            position: absolute;
            box-shadow: 0 20px 40px rgba(0,0,0,0.4);
        }

        .device-pc {
            width: 60%;
            height: 65%;
            border-radius: 12px;
            left: 5%;
            top: 15%;
            padding: 12px;
        }
        
        .device-pc::after {
            content: '';
            position: absolute;
            bottom: -15px;
            left: -5%;
            width: 110%;
            height: 15px;
            background: rgba(255, 255, 255, 0.08);
            border-radius: 4px 4px 12px 12px;
        }

        .device-mobile {
            width: 28%;
            height: 75%;
            border-radius: 24px;
            right: 5%;
            bottom: 5%;
            padding: 8px;
            z-index: 10;
        }

        .ui-band {
            background: rgba(255, 255, 255, 0.1);
            height: 12px;
            border-radius: 6px;
            margin-bottom: 8px;
        }
        
        .ui-band-short { width: 40%; }
        .ui-band-long { width: 80%; }

        .ui-draft {
            background: var(--color-primary);
            border-radius: 8px;
            flex: 1;
            margin-top: 8px;
            position: relative;
            overflow: hidden;
        }

        .ui-draft::before {
            content: '';
            position: absolute;
            top: 0; left: 0; right: 0; bottom: 0;
            background: linear-gradient(135deg, rgba(255,255,255,0.2) 0%, transparent 100%);
        }

        .sync-path {
            position: absolute;
            top: 45%;
            left: 55%;
            width: 30%;
            height: 2px;
            background: rgba(255, 255, 255, 0.1);
            transform: translateY(-50%);
            z-index: 5;
        }

        .sync-node {
            position: absolute;
            top: 50%;
            left: 0;
            width: 8px;
            height: 8px;
            background: var(--color-primary-light);
            border-radius: 50%;
            transform: translateY(-50%);
            box-shadow: 0 0 10px var(--color-primary-light);
            animation: syncFlow 2s infinite linear;
        }

        @keyframes syncFlow {
            0% { left: 0; opacity: 0; }
            20% { opacity: 1; }
            80% { opacity: 1; }
            100% { left: 100%; opacity: 0; }
        }

        .batch-tags {
            gap: 1rem;
            margin-bottom: 2.5rem;
        }

        .tag-cell {
            background: rgba(255, 255, 255, 0.1);
            border: 1px solid rgba(255, 255, 255, 0.2);
            padding: 0.5rem 1rem;
            border-radius: 100px;
            font-size: 0.875rem;
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }

        /* Stage 2: Compare/Features */
        .stage-compare {
            padding: 100px 0;
            background: var(--color-bg-light);
        }

        .crest-center {
            text-align: center;
            max-width: 700px;
            margin: 0 auto 4rem;
        }

        .batch-slides {
            gap: 2rem;
            justify-content: center;
        }

        .slide-feature {
            flex: 1;
            min-width: 280px;
            background: var(--color-surface);
            border-radius: var(--radius-lg);
            padding: 3rem 2.5rem;
            box-shadow: var(--shadow-sm);
            border: 1px solid rgba(0,0,0,0.02);
            transition: var(--transition);
            display: flex;
            flex-direction: column;
            align-items: flex-start;
        }

        .slide-feature:hover {
            transform: translateY(-8px);
            box-shadow: var(--shadow-md);
        }

        .glyph-shell {
            width: 64px;
            height: 64px;
            border-radius: var(--radius-md);
            background: var(--color-primary-light);
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 1.5rem;
            color: var(--color-primary);
        }

        .glyph-shell svg {
            width: 32px;
            height: 32px;
        }

        /* Stage 3: Steps (Collaboration) */
        .stage-steps {
            padding: 100px 0;
            background: var(--color-surface);
            border-top: 1px solid rgba(0,0,0,0.03);
        }

        .easel-steps {
            align-items: center;
            gap: 5rem;
        }

        .steps-plate {
            flex: 1.2;
            min-width: 300px;
            order: 2;
        }

        .steps-prose {
            flex: 1;
            min-width: 300px;
            order: 1;
        }

        .batch-index {
            display: flex;
            flex-direction: column;
            gap: 2rem;
            margin-top: 2.5rem;
        }

        .bullet-step {
            display: flex;
            gap: 1.5rem;
            align-items: flex-start;
        }

        .step-mark {
            width: 40px;
            height: 40px;
            border-radius: 50%;
            background: var(--color-bg-light);
            color: var(--color-primary);
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 700;
            font-size: 1.125rem;
            flex-shrink: 0;
            border: 1px solid rgba(106, 59, 226, 0.1);
        }

        .step-shell h3 {
            margin: 0 0 0.5rem 0;
            font-size: 1.125rem;
            color: var(--color-ink-main);
        }

        /* Data UI: Collaboration Mockup */
        .plate-collab {
            background: var(--color-bg-light);
            border-radius: var(--radius-lg);
            padding: 1.5rem;
            border: 1px solid rgba(0,0,0,0.05);
            box-shadow: 0 24px 48px rgba(0,0,0,0.06);
            position: relative;
        }

        .collab-crown {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding-bottom: 1rem;
            border-bottom: 1px solid rgba(0,0,0,0.05);
            margin-bottom: 1.5rem;
        }

        .collab-avatars {
            display: flex;
        }

        .avatar {
            width: 36px;
            height: 36px;
            border-radius: 50%;
            border: 2px solid var(--color-surface);
            background: var(--color-primary-light);
            margin-left: -10px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 12px;
            font-weight: bold;
            color: var(--color-primary-dark);
        }
        
        .avatar:first-child { margin-left: 0; background: #e2f5ec; color: #0d7f4f; }
        .avatar:last-child { background: #fff0e5; color: #c45a11; }

        .collab-share {
            background: var(--color-primary);
            color: #fff;
            padding: 6px 16px;
            border-radius: 100px;
            font-size: 13px;
            font-weight: 500;
        }

        .collab-canvas {
            background: var(--color-surface);
            border-radius: var(--radius-md);
            height: 200px;
            padding: 1.5rem;
            position: relative;
            box-shadow: inset 0 2px 10px rgba(0,0,0,0.02);
        }

        .cursor {
            position: absolute;
            display: flex;
            flex-direction: column;
            align-items: flex-start;
            z-index: 10;
            transition: all 0.5s ease-out;
        }

        .cursor-1 { top: 30%; left: 40%; animation: floatCursor1 4s ease-in-out infinite alternate; }
        .cursor-2 { top: 60%; left: 70%; animation: floatCursor2 5s ease-in-out infinite alternate; }

        @keyframes floatCursor1 { 0% { transform: translate(0, 0); } 100% { transform: translate(30px, 20px); } }
        @keyframes floatCursor2 { 0% { transform: translate(0, 0); } 100% { transform: translate(-40px, -15px); } }

        .cursor svg {
            width: 16px;
            height: 16px;
            filter: drop-shadow(0 2px 4px rgba(0,0,0,0.2));
        }

        .cursor-tag {
            background: #ff5722;
            color: #fff;
            font-size: 10px;
            padding: 2px 8px;
            border-radius: 4px;
            border-top-left-radius: 0;
            margin-top: -2px;
            margin-left: 8px;
            white-space: nowrap;
        }
        
        .cursor-1 .cursor-tag { background: #00bcd4; }
        .cursor-1 svg path { fill: #00bcd4; }
        .cursor-2 svg path { fill: #ff5722; }

        /* Footer (Base) */
        .base {
            background-color: var(--color-surface);
            padding: 4rem 0 2rem;
            border-top: 1px solid rgba(0,0,0,0.05);
            margin-top: auto;
        }

        .spine {
            display: flex;
            justify-content: space-between;
            align-items: center;
            border-bottom: 1px solid rgba(0,0,0,0.05);
            padding-bottom: 2rem;
            margin-bottom: 2rem;
        }

        .spine-brand {
            font-size: 1.5rem;
            font-weight: 700;
            color: var(--color-primary);
        }

        .spine-links {
            display: flex;
            gap: 1.5rem;
        }

        .spine-links a {
            color: var(--color-ink-sub);
            text-decoration: none;
            font-size: 0.875rem;
            transition: color var(--transition);
        }

        .spine-links a:hover {
            color: var(--color-primary);
        }

        .note {
            text-align: center;
            color: var(--color-ink-sub);
            font-size: 0.875rem;
        }

        /* Responsive */
        @media (max-width: 1024px) {
            .easel-intro, .easel-steps {
                flex-direction: column;
                text-align: center;
                gap: 3rem;
            }
            
            .prose-lead {
                margin: 0 auto 2rem;
            }
            
            .batch-tags {
                justify-content: center;
            }
            
            .steps-plate {
                order: 1;
                width: 100%;
            }
            .steps-prose {
                order: 2;
                text-align: left;
            }
        }

        @media (max-width: 768px) {
            .crest-mega { font-size: 2.5rem; }
            .stage-intro { padding: 80px 0 60px; }
            .stage-compare, .stage-steps { padding: 60px 0; }
            
            .index { display: none; } /* Simplified for mobile, assuming a hamburger in real life, but hidden per instructions to keep exact HTML */
            /* Actually, prompt says "必须完整输出以下所有菜单项... 不允许删减". So I cannot hide it completely if it implies removing elements. I will just let it wrap or scroll. */
            .index {
                display: flex;
                overflow-x: auto;
                padding-bottom: 10px;
                width: 100%;
                justify-content: flex-start;
            }
            .ribbon { height: auto; padding: 1rem 0; flex-direction: column; gap: 1rem; align-items: flex-start;}
            
            .spine {
                flex-direction: column;
                gap: 1.5rem;
            }
        }

.ribbon-crown .ribbon-binder{
            max-width: 1280px;
            margin: 0 auto;
            padding: 0 2rem;
            width: 100%;
            display: flex;
            flex-wrap: wrap;
            min-width: 0;
        }

.ribbon-crown{
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            z-index: 100;
            background: rgba(15, 16, 22, 0.85);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            border-bottom: 1px solid rgba(255, 255, 255, 0.05);
        }

.ribbon-crown .ribbon-ribbon{
            display: flex;
            flex-wrap: wrap;
            justify-content: space-between;
            align-items: center;
            height: 72px;
            min-width: 0;
        }

.ribbon-crown .ribbon-stamp{
            display: flex;
            align-items: center;
            min-width: 0;
        }

.ribbon-crown .ribbon-stamp img{
            height: 32px;
            width: auto;
            display: block;
        }

.ribbon-crown .ribbon-index{
            display: flex;
            flex-wrap: wrap;
            gap: 1.5rem;
            min-width: 0;
        }

.ribbon-crown .ribbon-xref{
            color: rgba(255, 255, 255, 0.7);
            font-size: 0.95rem;
            font-weight: 500;
            transition: all 0.35s ease;
            padding: 0.5rem 0;
            position: relative;
        }

.ribbon-crown .ribbon-xref:hover{
            color: #ffffff;
        }

.ribbon-crown .ribbon-xref.active{
            color: #ffffff;
        }

.ribbon-crown .ribbon-xref.active::after{
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 100%;
            height: 2px;
            background: #6a3be2;
            border-radius: 2px;
        }

@media (max-width: 768px){.ribbon-crown .ribbon-index{
                display: none; 
            }}

.ribbon-crown {
    background: rgb(15, 16, 22);
    background-image: none;
}

.spine-base {
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--color-ink-main);
}
.spine-base,
.spine-base *,
.spine-base *::before,
.spine-base *::after {
    box-sizing: border-box;
}

.spine-base nav,
.spine-base div,
.spine-base section,
.spine-base article,
.spine-base aside,
.spine-base p,
.spine-base h1,
.spine-base h2,
.spine-base h3,
.spine-base h4,
.spine-base h5,
.spine-base h6,
.spine-base a {
    margin: 0;
    padding: 0;
    font: inherit;
    color: inherit;
    letter-spacing: inherit;
    line-height: inherit;
}

.spine-base p,
.spine-base h1,
.spine-base h2,
.spine-base h3,
.spine-base h4,
.spine-base h5,
.spine-base h6 {
    text-decoration: none;
}

.spine-base img {
    display: block;
    max-width: 100%;
    height: auto;
    border: 0;
}

.spine-base {
    box-shadow: none;
    filter: none;
    text-shadow: none;
    background-image: none;
    border-top: none;
    border-left: none;
    border-right: none;
    outline: none;
}

.spine-base a,
.spine-base a:hover,
.spine-base a:focus,
.spine-base a:active {
    background: transparent;
    box-shadow: none;
    outline: none;
    text-decoration: none;
}

.spine-base .spine-binder{
            max-width: 1280px;
            margin: 0 auto;
            padding: 0 2rem;
            width: 100%;
            display: flex;
            flex-wrap: wrap;
            min-width: 0;
        }

.spine-base .spine-xref{
            color: rgba(255, 255, 255, 0.7);
            font-size: 0.95rem;
            font-weight: 500;
            transition: all 0.35s ease;
            padding: 0.5rem 0;
            position: relative;
        }

.spine-base .spine-xref:hover{
            color: #ffffff;
        }

.spine-base .spine-xref.active{
            color: #ffffff;
        }

.spine-base .spine-xref.active::after{
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 100%;
            height: 2px;
            background: #6a3be2;
            border-radius: 2px;
        }

.spine-base{
            background: #0f1016;
            color: rgba(255, 255, 255, 0.7);
            padding: 8rem 0 2rem;
            margin-top: auto;
        }

.spine-base .spine-spine{
            display: flex;
            flex-wrap: wrap;
            gap: 8rem;
            justify-content: space-between;
            min-width: 0;
            border-bottom: 1px solid rgba(255,255,255,0.1);
            padding-bottom: 4rem;
            margin-bottom: 2rem;
        }

.spine-base .spine-spine-col{
            flex: 1 1 200px;
            min-width: 0;
            display: flex;
            flex-direction: column;
            gap: 1rem;
        }

.spine-base .spine-spine-col .spine-crest{
            color: #ffffff;
            font-size: 1.2rem;
            margin-bottom: 0.5rem;
        }

.spine-base .spine-spine-col .spine-xref{
            color: rgba(255, 255, 255, 0.7);
            font-size: 0.9rem;
        }

.spine-base .spine-spine-col .spine-xref:hover{
            color: #ece5fe;
            padding-left: 4px;
        }

.spine-base .spine-endcap{
            text-align: center;
            font-size: 0.85rem;
            color: rgba(255,255,255,0.4);
        }