/* ============================================
   上瘾模型 — 视觉系统
   参考：Notion docs / Linear / Readwise
   ============================================ */

/* ---- 变量系统 ---- */
:root {
    /* 色彩 */
    --c-bg: #fafaf9;
    --c-bg-alt: #f5f5f4;
    --c-card: #ffffff;
    --c-text: #1c1917;
    --c-text-2: #44403c;
    --c-text-3: #78716c;
    --c-text-4: #a8a29e;
    --c-border: #e7e5e4;
    --c-border-light: #f5f5f4;

    /* 强调色 */
    --c-accent: #ea580c;
    --c-accent-light: #fff7ed;
    --c-accent-soft: #fdba74;

    /* 辅助色 */
    --c-green: #15803d;
    --c-green-light: #f0fdf4;
    --c-green-soft: #86efac;
    --c-blue: #0369a1;
    --c-blue-light: #f0f9ff;
    --c-blue-soft: #7dd3fc;
    --c-red: #dc2626;
    --c-red-light: #fef2f2;

    /* 排版 */
    --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;

    /* 间距 */
    --s-section: 120px;
    --s-inner: 720px;

    /* 圆角 */
    --r: 12px;
    --r-lg: 16px;
    --r-xl: 20px;

    /* 阴影 */
    --shadow: 0 1px 3px rgba(0,0,0,0.04), 0 4px 12px rgba(0,0,0,0.03);
    --shadow-hover: 0 4px 12px rgba(0,0,0,0.06), 0 12px 32px rgba(0,0,0,0.04);

    /* 过渡 */
    --ease: cubic-bezier(0.4, 0, 0.2, 1);
}

/* ---- 基础 ---- */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font);
    background: var(--c-bg);
    color: var(--c-text);
    line-height: 1.75;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }

/* ---- 阅读进度条 ---- */
.read-progress {
    position: fixed;
    top: 0; left: 0;
    height: 2px;
    background: var(--c-accent);
    z-index: 10000;
    transition: width 0.1s linear;
    width: 0%;
}

/* ---- 侧边目录 ---- */
.toc {
    position: fixed;
    left: 0; top: 0;
    width: 220px;
    height: 100vh;
    padding: 32px 20px;
    z-index: 100;
    display: none;
}

.toc-inner {
    position: sticky;
    top: 32px;
}

.toc-title {
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--c-text-4);
    margin-bottom: 16px;
    padding-left: 12px;
}

.toc-nav {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.toc-link {
    display: block;
    padding: 6px 12px;
    border-radius: 6px;
    font-size: 13px;
    color: var(--c-text-3);
    transition: all 0.2s var(--ease);
    border-left: 2px solid transparent;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.toc-link:hover {
    color: var(--c-text);
    background: var(--c-bg-alt);
}

.toc-link.active {
    color: var(--c-accent);
    background: var(--c-accent-light);
    border-left-color: var(--c-accent);
    font-weight: 600;
}

/* 大屏显示目录 */
@media (min-width: 1100px) {
    .toc { display: block; }
    body { padding-left: 220px; }
}

/* ============================================
   封面
   ============================================ */
.cover {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 80px 24px;
    position: relative;
    background: linear-gradient(180deg, #fafaf9 0%, #f5f5f4 100%);
}

.cover-inner {
    max-width: 640px;
}

.cover-tag {
    display: inline-block;
    padding: 5px 16px;
    background: var(--c-accent-light);
    color: var(--c-accent);
    border-radius: 100px;
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 28px;
    letter-spacing: 0.5px;
}

.cover-title {
    font-size: clamp(2.8rem, 6vw, 4.2rem);
    font-weight: 900;
    line-height: 1.05;
    letter-spacing: -0.03em;
    color: var(--c-text);
    margin-bottom: 16px;
}

.cover-subtitle {
    font-size: 1.15rem;
    color: var(--c-text-3);
    line-height: 1.7;
    margin-bottom: 36px;
    max-width: 480px;
    margin-left: auto;
    margin-right: auto;
}

/* Hook 循环动画 */
.hook-cycle {
    max-width: 400px;
    margin: 0 auto 40px;
    position: relative;
}

.hc-svg {
    width: 100%;
    height: auto;
}

.hc-path {
    stroke-dasharray: 8 4;
    animation: pathDash 2s linear infinite;
}

@keyframes pathDash {
    to { stroke-dashoffset: -24; }
}

.hc-node {
    cursor: default;
    transition: transform 0.3s var(--ease);
}

.hc-node circle {
    transition: all 0.4s var(--ease);
}

.hc-node.active circle {
    stroke: var(--c-accent);
    stroke-width: 3;
    fill: var(--c-accent-light);
}

.hc-node.active text {
    fill: var(--c-accent) !important;
}

.hc-node:hover {
    transform: scale(1.05);
}

.hc-label {
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--c-text-4);
    padding: 4px 12px;
    background: var(--c-card);
    border: 1px solid var(--c-border);
    border-radius: 100px;
}

.cover-cta {
    display: flex;
    gap: 12px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 40px;
}

.btn-main {
    display: inline-flex;
    align-items: center;
    padding: 12px 28px;
    background: var(--c-text);
    color: white;
    border-radius: 100px;
    font-size: 15px;
    font-weight: 600;
    transition: all 0.25s var(--ease);
    border: none;
    cursor: pointer;
    font-family: inherit;
}

.btn-main:hover {
    background: var(--c-text-2);
    transform: translateY(-1px);
}

.btn-ghost {
    display: inline-flex;
    align-items: center;
    padding: 12px 28px;
    background: transparent;
    color: var(--c-text-3);
    border-radius: 100px;
    font-size: 15px;
    font-weight: 500;
    transition: all 0.25s var(--ease);
    border: 1.5px solid var(--c-border);
    cursor: pointer;
    font-family: inherit;
}

.btn-ghost:hover {
    border-color: var(--c-text-3);
    color: var(--c-text);
}

.cover-meta {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-size: 13px;
    color: var(--c-text-4);
}

.meta-dot { color: var(--c-border); }

.cover-scroll {
    position: absolute;
    bottom: 32px;
    left: 50%;
    transform: translateX(-50%);
    color: var(--c-text-4);
    animation: bounceDown 2s ease-in-out infinite;
}

@keyframes bounceDown {
    0%, 100% { transform: translateX(-50%) translateY(0); }
    50% { transform: translateX(-50%) translateY(8px); }
}

/* ============================================
   章节通用
   ============================================ */
.chapter {
    padding: var(--s-section) 24px;
}

.chapter-alt {
    background: var(--c-bg-alt);
}

.chapter-inner {
    max-width: var(--s-inner);
    margin: 0 auto;
}

.chapter-num {
    display: block;
    font-size: 13px;
    font-weight: 700;
    color: var(--c-accent);
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 12px;
}

.chapter-title {
    font-size: clamp(1.6rem, 3.5vw, 2.2rem);
    font-weight: 800;
    line-height: 1.2;
    letter-spacing: -0.02em;
    margin-bottom: 12px;
    color: var(--c-text);
}

.chapter-lead {
    font-size: 1.05rem;
    color: var(--c-text-3);
    line-height: 1.7;
    margin-bottom: 48px;
    max-width: 560px;
}

/* ============================================
   01 定义
   ============================================ */
.definition-box {
    background: var(--c-card);
    border: 1px solid var(--c-border);
    border-radius: var(--r-xl);
    padding: 40px;
    margin-bottom: 40px;
    position: relative;
    box-shadow: var(--shadow);
}

.def-quote-mark {
    font-family: Georgia, serif;
    font-size: 4rem;
    line-height: 1;
    color: var(--c-accent-soft);
    position: absolute;
    top: 16px;
    left: 24px;
}

.definition-text {
    font-size: 1.25rem;
    line-height: 1.7;
    color: var(--c-text);
    padding-top: 16px;
    padding-left: 8px;
}

.definition-text strong {
    color: var(--c-accent);
    font-weight: 700;
}

.definition-by {
    font-size: 14px;
    color: var(--c-text-4);
    margin-top: 16px;
    padding-left: 8px;
}

/* 比喻区 */
.analogy-box {
    margin-bottom: 48px;
}

.analogy-box h3 {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 20px;
    color: var(--c-text-2);
}

.analogy-content {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: 20px;
    align-items: center;
}

.analogy-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    background: var(--c-card);
    border: 1px solid var(--c-border);
    border-radius: var(--r-lg);
    padding: 24px;
    box-shadow: var(--shadow);
}

.analogy-icon {
    width: 44px;
    height: 44px;
    border-radius: var(--r);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
    flex-shrink: 0;
}

.ai-gray { background: var(--c-bg-alt); }
.ai-accent { background: var(--c-accent-light); }

.analogy-text strong {
    display: block;
    font-size: 1rem;
    font-weight: 700;
    color: var(--c-text);
    margin-bottom: 4px;
}

.analogy-text span {
    font-size: 14px;
    color: var(--c-text-3);
    line-height: 1.6;
}

.analogy-vs {
    font-size: 13px;
    font-weight: 700;
    color: var(--c-text-4);
    text-transform: uppercase;
    letter-spacing: 2px;
}

/* Hook 概览 */
.hook-overview {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    margin-bottom: 56px;
    flex-wrap: wrap;
}

.ho-step {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 4px;
    padding: 20px 16px;
    background: var(--c-card);
    border: 1px solid var(--c-border);
    border-radius: var(--r-xl);
    min-width: 120px;
    box-shadow: var(--shadow);
    transition: all 0.3s var(--ease);
}

.ho-step:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-hover);
    border-color: var(--c-accent-soft);
}

.ho-num {
    font-size: 10px;
    font-weight: 700;
    color: var(--c-text-4);
    letter-spacing: 1px;
}

.ho-icon { font-size: 1.6rem; }

.ho-name {
    font-size: 15px;
    font-weight: 700;
    color: var(--c-text);
}

.ho-desc {
    font-size: 12px;
    color: var(--c-text-4);
    max-width: 100px;
}

.ho-arrow {
    font-size: 1.3rem;
    color: var(--c-text-4);
    font-weight: 300;
}

/* ============================================
   02 为什么重要
   ============================================ */
.problems-grid {
    display: grid;
    gap: 20px;
    margin-bottom: 36px;
}

.problem-card {
    background: var(--c-card);
    border: 1px solid var(--c-border);
    border-radius: var(--r-xl);
    padding: 32px;
    box-shadow: var(--shadow);
    transition: all 0.3s var(--ease);
}

.problem-card:hover {
    box-shadow: var(--shadow-hover);
    transform: translateY(-2px);
}

.problem-num {
    font-size: 13px;
    font-weight: 700;
    color: var(--c-accent);
    margin-bottom: 8px;
    letter-spacing: 1px;
}

.problem-card h3 {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--c-text);
}

.problem-card > p {
    font-size: 0.95rem;
    color: var(--c-text-2);
    line-height: 1.7;
    margin-bottom: 16px;
}

.problem-card > p strong { color: var(--c-text); }

.problem-example {
    background: var(--c-bg-alt);
    border-radius: var(--r);
    padding: 14px 18px;
    font-size: 14px;
    color: var(--c-text-3);
    line-height: 1.6;
}

.pe-label {
    display: block;
    font-size: 10px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--c-text-4);
    margin-bottom: 4px;
}

/* 洞察横幅 */
.insight-banner {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    background: var(--c-card);
    border: 1px solid var(--c-accent-soft);
    border-radius: var(--r-xl);
    padding: 24px 28px;
    box-shadow: var(--shadow);
}

.insight-icon {
    font-size: 1.5rem;
    flex-shrink: 0;
    margin-top: 2px;
}

.insight-banner p {
    font-size: 0.95rem;
    color: var(--c-text-2);
    line-height: 1.7;
}

.insight-banner strong { color: var(--c-text); }

/* ============================================
   03 四步详解
   ============================================ */
.step-detail {
    background: var(--c-card);
    border: 1px solid var(--c-border);
    border-radius: var(--r-xl);
    padding: 36px;
    margin-bottom: 24px;
    box-shadow: var(--shadow);
}

.sd-header {
    display: flex;
    align-items: center;
    gap: 14px;
    margin-bottom: 20px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--c-border-light);
}

.sd-num {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: var(--c-text);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    font-weight: 700;
    flex-shrink: 0;
}

.sd-header h3 {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--c-text);
}

.sd-body > p {
    font-size: 0.97rem;
    color: var(--c-text-2);
    line-height: 1.7;
    margin-bottom: 24px;
}

.sd-body > p strong { color: var(--c-text); }

/* 触发类型 */
.trigger-types {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-bottom: 24px;
}

.tt-card {
    background: var(--c-bg-alt);
    border-radius: var(--r-lg);
    padding: 24px;
    position: relative;
}

.tt-badge {
    display: inline-block;
    padding: 3px 10px;
    border-radius: 100px;
    font-size: 10px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 12px;
}

.tt-external .tt-badge { background: var(--c-blue-light); color: var(--c-blue); }
.tt-internal .tt-badge { background: var(--c-accent-light); color: var(--c-accent); }

.tt-icon { font-size: 2rem; display: block; margin-bottom: 8px; }

.tt-desc {
    font-size: 14px;
    color: var(--c-text-2);
    line-height: 1.6;
    display: block;
    margin-bottom: 12px;
}

.tt-example {
    font-size: 13px;
    color: var(--c-text-3);
    line-height: 1.5;
    padding: 10px 14px;
    background: var(--c-card);
    border-radius: var(--r);
    border: 1px solid var(--c-border);
}

.tt-example strong { color: var(--c-text); }

/* 福格公式 */
.bmat-formula {
    background: var(--c-bg-alt);
    border-radius: var(--r-lg);
    padding: 28px;
    margin-bottom: 24px;
    text-align: center;
}

.bf-label {
    display: block;
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--c-text-4);
    margin-bottom: 16px;
}

.bf-formula {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    margin-bottom: 12px;
    flex-wrap: wrap;
}

.bf-b, .bf-m, .bf-a, .bf-t {
    font-size: 2.5rem;
    font-weight: 800;
    font-family: Georgia, serif;
}

.bf-b { color: var(--c-accent); }
.bf-m { color: var(--c-blue); }
.bf-a { color: var(--c-green); }
.bf-t { color: var(--c-red); }

.bf-eq { font-size: 2rem; color: var(--c-text-3); font-weight: 300; }
.bf-op { font-size: 1.5rem; color: var(--c-text-4); }

.bf-legend {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    flex-wrap: wrap;
    font-size: 13px;
    color: var(--c-text-3);
    margin-bottom: 12px;
}

.bf-legend strong { color: var(--c-text); }

.bf-conclusion {
    font-size: 14px;
    color: var(--c-text-2);
    line-height: 1.6;
    max-width: 480px;
    margin: 0 auto;
}

.bf-conclusion strong { color: var(--c-accent); }

.ability-examples {
    margin-bottom: 24px;
}

.ae-item {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.ae-compare {
    font-size: 13px;
    padding: 12px 16px;
    border-radius: var(--r);
    line-height: 1.5;
}

.ae-compare:first-child {
    background: var(--c-red-light);
    color: #991b1b;
}

.ae-compare:last-child {
    background: var(--c-green-light);
    color: #14532d;
}

/* 奖励类型 */
.reward-types {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
    margin-bottom: 24px;
}

.rt-card {
    background: var(--c-bg-alt);
    border-radius: var(--r-lg);
    padding: 24px;
    text-align: center;
    transition: all 0.3s var(--ease);
}

.rt-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-hover);
}

.rt-icon { font-size: 2.2rem; display: block; margin-bottom: 8px; }

.rt-name {
    display: block;
    font-size: 15px;
    font-weight: 700;
    color: var(--c-text);
    margin-bottom: 6px;
}

.rt-card > p {
    font-size: 13px;
    color: var(--c-text-3);
    line-height: 1.5;
    margin-bottom: 12px;
}

.rt-example {
    font-size: 12px;
    color: var(--c-text-2);
    line-height: 1.5;
    padding: 10px 12px;
    background: var(--c-card);
    border-radius: var(--r);
    border: 1px solid var(--c-border);
}

/* 老虎机 */
.slot-machine {
    background: var(--c-bg-alt);
    border-radius: var(--r-lg);
    padding: 28px;
    margin-bottom: 24px;
    text-align: center;
}

.sm-label {
    display: block;
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--c-text-4);
    margin-bottom: 16px;
}

.sm-visual {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    margin-bottom: 16px;
}

.sm-reel {
    width: 48px;
    height: 48px;
    border-radius: var(--r);
    background: var(--c-card);
    border: 2px solid var(--c-border);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    animation: slotSpin 3s ease-in-out infinite;
}

.sm-reel:nth-child(2) { animation-delay: 0.2s; }
.sm-reel:nth-child(3) { animation-delay: 0.4s; }

@keyframes slotSpin {
    0%, 70%, 100% { transform: translateY(0); }
    15% { transform: translateY(-6px); }
    30% { transform: translateY(3px); }
}

.slot-machine > p {
    font-size: 14px;
    color: var(--c-text-2);
    line-height: 1.6;
    max-width: 400px;
    margin: 0 auto;
}

.slot-machine strong { color: var(--c-accent); }

/* 投入类型 */
.investment-types {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-bottom: 24px;
}

.inv-item {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 16px 20px;
    background: var(--c-bg-alt);
    border-radius: var(--r-lg);
    transition: all 0.2s var(--ease);
}

.inv-item:hover {
    background: var(--c-card);
    box-shadow: var(--shadow);
    transform: translateX(4px);
}

.inv-icon { font-size: 1.6rem; flex-shrink: 0; }

.inv-content { flex: 1; }

.inv-content strong {
    display: block;
    font-size: 15px;
    font-weight: 700;
    color: var(--c-text);
    margin-bottom: 2px;
}

.inv-content span {
    font-size: 14px;
    color: var(--c-text-3);
    line-height: 1.5;
}

/* 步骤提示 */
.sd-tip {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding: 16px 20px;
    background: var(--c-blue-light);
    border-radius: var(--r);
    border-left: 3px solid var(--c-blue);
}

.sd-tip-icon { font-size: 1.2rem; flex-shrink: 0; }
.sd-tip div { font-size: 14px; color: var(--c-text-2); line-height: 1.6; }
.sd-tip strong { color: var(--c-text); }

/* ============================================
   04 案例
   ============================================ */
.case-block {
    background: var(--c-card);
    border: 1px solid var(--c-border);
    border-radius: var(--r-xl);
    overflow: hidden;
    margin-bottom: 24px;
    box-shadow: var(--shadow);
    transition: all 0.3s var(--ease);
}

.case-block:hover {
    box-shadow: var(--shadow-hover);
}

.case-header {
    padding: 28px 32px;
    background: var(--c-bg-alt);
    border-bottom: 1px solid var(--c-border-light);
}

.case-badge {
    display: inline-block;
    padding: 3px 10px;
    background: var(--c-accent-light);
    color: var(--c-accent);
    border-radius: 100px;
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 8px;
}

.case-header h3 {
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--c-text);
}

.case-body { padding: 28px 32px; }

.case-situation {
    font-size: 0.95rem;
    color: var(--c-text-2);
    line-height: 1.7;
    margin-bottom: 24px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--c-border-light);
}

.case-situation strong { color: var(--c-text); }

/* 案例流程 */
.case-process-flow {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
    margin-bottom: 24px;
}

.cpf-step {
    padding: 20px;
    background: var(--c-bg-alt);
    border-radius: var(--r-lg);
    transition: all 0.3s var(--ease);
}

.cpf-step:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.cpf-tag {
    display: inline-block;
    padding: 3px 10px;
    background: var(--c-text);
    color: white;
    border-radius: 100px;
    font-size: 10px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 10px;
}

.cpf-step p {
    font-size: 14px;
    color: var(--c-text-2);
    line-height: 1.6;
}

.cpf-step strong { color: var(--c-text); font-size: 13px; }

.case-result-box {
    background: var(--c-green-light);
    border: 1px solid var(--c-green-soft);
    border-radius: var(--r-lg);
    padding: 18px 22px;
}

.crb-label {
    display: block;
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--c-green);
    margin-bottom: 6px;
}

.case-result-box p {
    font-size: 14px;
    color: #14532d;
    line-height: 1.6;
}

/* ============================================
   05 练习
   ============================================ */
.practice-scene {
    background: var(--c-card);
    border: 1px solid var(--c-border);
    border-radius: var(--r-xl);
    overflow: hidden;
    margin-bottom: 24px;
    box-shadow: var(--shadow);
}

.ps-header {
    padding: 24px 28px;
    background: var(--c-bg-alt);
    border-bottom: 1px solid var(--c-border-light);
}

.ps-num {
    display: block;
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--c-accent);
    margin-bottom: 6px;
}

.ps-header h3 {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--c-text);
}

.ps-body { padding: 24px 28px; }

.ps-setup, .ps-question {
    font-size: 0.95rem;
    color: var(--c-text-2);
    line-height: 1.7;
    margin-bottom: 12px;
}

.ps-question { font-size: 1rem; margin-bottom: 20px; }
.ps-question strong { color: var(--c-text); }

.ps-options {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.ps-opt {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding: 16px 18px;
    background: var(--c-bg-alt);
    border: 2px solid transparent;
    border-radius: var(--r-lg);
    cursor: pointer;
    transition: all 0.2s var(--ease);
    text-align: left;
    font-family: inherit;
    font-size: 15px;
    color: var(--c-text);
    width: 100%;
}

.ps-opt:hover {
    border-color: var(--c-border);
    background: var(--c-bg);
}

.ps-opt:disabled { cursor: default; }

.ps-opt-letter {
    width: 28px; height: 28px;
    border-radius: 50%;
    background: var(--c-card);
    border: 1.5px solid var(--c-border);
    display: flex; align-items: center; justify-content: center;
    font-size: 12px; font-weight: 700;
    color: var(--c-text-3);
    flex-shrink: 0;
    transition: all 0.2s;
}

.ps-opt:hover .ps-opt-letter {
    border-color: var(--c-text-3);
    color: var(--c-text-2);
}

.ps-opt-right {
    border-color: var(--c-green) !important;
    background: var(--c-green-light) !important;
}
.ps-opt-right .ps-opt-letter {
    background: var(--c-green) !important;
    border-color: var(--c-green) !important;
    color: white !important;
}

.ps-opt-wrong {
    border-color: var(--c-red) !important;
    background: var(--c-red-light) !important;
}
.ps-opt-wrong .ps-opt-letter {
    background: var(--c-red) !important;
    border-color: var(--c-red) !important;
    color: white !important;
}

.ps-feedback {
    margin-top: 14px;
    padding: 14px 18px;
    border-radius: var(--r);
    font-size: 14px;
    line-height: 1.6;
    display: none;
    align-items: flex-start;
    gap: 10px;
    background: var(--c-blue-light);
    border-left: 3px solid var(--c-blue);
}

.ps-fb-show { display: flex; }

.ps-fb-icon { font-size: 1.2rem; flex-shrink: 0; }

/* ============================================
   06 常见误区
   ============================================ */
.mistakes-list {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.mistake-item {
    display: flex;
    gap: 20px;
    background: var(--c-card);
    border: 1px solid var(--c-border);
    border-radius: var(--r-xl);
    padding: 28px 32px;
    box-shadow: var(--shadow);
    transition: all 0.3s var(--ease);
}

.mistake-item:hover {
    box-shadow: var(--shadow-hover);
}

.mistake-num {
    width: 32px; height: 32px;
    border-radius: 50%;
    background: var(--c-red-light);
    color: var(--c-red);
    display: flex; align-items: center; justify-content: center;
    font-size: 12px; font-weight: 700;
    flex-shrink: 0;
    margin-top: 2px;
}

.mistake-content { flex: 1; }
.mistake-content h3 {
    font-size: 1.05rem;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--c-text);
}
.mistake-content > p {
    font-size: 0.95rem;
    color: var(--c-text-2);
    line-height: 1.7;
    margin-bottom: 14px;
}
.mistake-content > p strong { color: var(--c-text); }

.mistake-example {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.me-wrong, .me-right {
    font-size: 13px;
    padding: 10px 14px;
    border-radius: var(--r);
    line-height: 1.5;
}
.me-wrong { background: var(--c-red-light); color: #991b1b; }
.me-right { background: var(--c-green-light); color: #14532d; }

/* ============================================
   07 自检清单
   ============================================ */
.checklist {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-bottom: 28px;
}

.check-item {
    display: flex;
    align-items: flex-start;
    gap: 14px;
    padding: 18px 22px;
    background: var(--c-card);
    border: 1px solid var(--c-border);
    border-radius: var(--r-lg);
    cursor: pointer;
    transition: all 0.2s var(--ease);
    box-shadow: var(--shadow);
}

.check-item:hover {
    border-color: var(--c-accent-soft);
    box-shadow: var(--shadow-hover);
}

.check-box {
    width: 20px; height: 20px;
    border: 2px solid var(--c-border);
    border-radius: 5px;
    appearance: none;
    -webkit-appearance: none;
    flex-shrink: 0;
    margin-top: 2px;
    cursor: pointer;
    transition: all 0.2s;
    position: relative;
}

.check-box:checked {
    background: var(--c-accent);
    border-color: var(--c-accent);
}

.check-box:checked::after {
    content: '';
    position: absolute;
    left: 5px; top: 1px;
    width: 5px; height: 10px;
    border: solid white;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
}

.check-text {
    font-size: 0.97rem;
    color: var(--c-text-2);
    line-height: 1.6;
}

.check-text strong { color: var(--c-text); font-weight: 600; }

.checklist-result {
    text-align: center;
    padding: 20px;
    background: var(--c-card);
    border: 1px solid var(--c-border);
    border-radius: var(--r-lg);
    font-size: 1rem;
    color: var(--c-text-3);
    box-shadow: var(--shadow);
}

.checklist-result strong { color: var(--c-text); }

.cr-ok { border-color: var(--c-accent-soft); background: var(--c-accent-light); color: #9a3412; }
.cr-good { border-color: var(--c-green-soft); background: var(--c-green-light); color: #14532d; }

/* ============================================
   08 总结
   ============================================ */
.summary-card {
    background: var(--c-card);
    border: 1px solid var(--c-border);
    border-radius: var(--r-xl);
    padding: 40px;
    margin-bottom: 40px;
    box-shadow: var(--shadow);
}

.hook-summary {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    margin-bottom: 16px;
    flex-wrap: wrap;
}

.sv-node {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    text-align: center;
}

.sv-circle {
    width: 72px; height: 72px;
    border-radius: 50%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 2px;
}

.sv-trigger { background: linear-gradient(135deg, #0369a1, #0ea5e9); }
.sv-action { background: linear-gradient(135deg, #059669, #34d399); }
.sv-reward { background: linear-gradient(135deg, var(--c-accent), #ea580c); }
.sv-invest { background: linear-gradient(135deg, #7c3aed, #a78bfa); }

.sv-icon { font-size: 1.4rem; }
.sv-name { font-size: 12px; font-weight: 700; color: white; letter-spacing: 1px; }

.sv-desc {
    font-size: 12px;
    color: var(--c-text-3);
    line-height: 1.5;
}

.sv-connector {
    display: flex;
    align-items: center;
    color: var(--c-text-4);
}

.hook-loop-back {
    text-align: center;
    margin-bottom: 24px;
    position: relative;
}

.hook-loop-back svg {
    max-width: 400px;
}

.hlb-label {
    display: inline-block;
    font-size: 12px;
    font-weight: 700;
    color: var(--c-accent);
    padding: 4px 12px;
    background: var(--c-accent-light);
    border-radius: 100px;
    margin-top: -20px;
}

.summary-formula {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    flex-wrap: wrap;
    padding-top: 24px;
    border-top: 1px solid var(--c-border-light);
}

.sf-left, .sf-right {
    font-size: 14px;
    font-weight: 700;
    padding: 8px 16px;
    border-radius: var(--r);
}

.sf-left { background: var(--c-bg-alt); color: var(--c-text-3); border: 1px solid var(--c-border); }
.sf-right { background: var(--c-accent-light); color: var(--c-accent); border: 1px solid var(--c-accent-soft); }

.sf-op { font-size: 13px; color: var(--c-text-4); }
.sf-vs { font-size: 12px; font-weight: 700; color: var(--c-text-4); text-transform: uppercase; letter-spacing: 1px; }

.final-quote {
    text-align: center;
    max-width: 520px;
    margin: 0 auto;
    padding: 32px 0;
}

.final-quote p {
    font-size: 1.25rem;
    color: var(--c-text-2);
    line-height: 1.8;
    font-style: italic;
}

.final-quote p strong { color: var(--c-accent); font-style: normal; }

/* ============================================
   页脚
   ============================================ */
.site-footer {
    text-align: center;
    padding: 48px 24px;
    background: var(--c-text);
    color: var(--c-text-4);
}

.site-footer p { font-size: 14px; }
.sf-sub { margin-top: 4px; font-size: 13px; opacity: 0.7; }

/* ============================================
   滚动显示动画
   ============================================ */
.reveal {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.6s var(--ease), transform 0.6s var(--ease);
}

.reveal.is-visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================
   响应式
   ============================================ */
@media (max-width: 768px) {
    :root { --s-section: 72px; }

    .cover-title { font-size: 2.4rem; }
    .cover-cta { flex-direction: column; align-items: center; }
    .cover-meta { flex-wrap: wrap; }

    .analogy-content { grid-template-columns: 1fr; }
    .analogy-vs { text-align: center; }

    .hook-overview { flex-direction: column; }
    .ho-arrow { transform: rotate(90deg); }

    .trigger-types { grid-template-columns: 1fr; }
    .reward-types { grid-template-columns: 1fr; }
    .case-process-flow { grid-template-columns: 1fr; }
    .bf-formula { font-size: 1.8rem; }
    .bf-legend { flex-direction: column; gap: 4px; }

    .mistake-item { flex-direction: column; gap: 12px; }

    .hook-summary { flex-direction: column; }
    .sv-connector { transform: rotate(90deg); }

    .definition-box { padding: 28px 20px; }
    .step-detail { padding: 24px; }
    .case-body { padding: 20px; }
    .case-header { padding: 20px; }
    .ps-body { padding: 20px; }

    .hook-cycle { max-width: 280px; }
}

@media (max-width: 480px) {
    .chapter-title { font-size: 1.4rem; }
    .definition-text { font-size: 1.05rem; }
    .btn-main, .btn-ghost { width: 100%; justify-content: center; }
}

/* ============================================
   滚动条
   ============================================ */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--c-bg); }
::-webkit-scrollbar-thumb { background: var(--c-border); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--c-text-4); }

/* 减少动画 */
@media (prefers-reduced-motion: reduce) {
    * { animation: none !important; transition: none !important; }
}