/* ========== 案例详情页专用样式 ========== */
/* 复用 style.css 中的 CSS 变量和基础样式 */

/* ========== 顶部返回导航 ========== */
.case-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 16px 0;
  background: rgba(249, 249, 249, 0.9);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border-light);
  transition: var(--transition);
}

.case-nav .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.case-nav-back {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: var(--transition);
}

.case-nav-back:hover {
  color: var(--color-primary);
}

.case-nav-back svg {
  width: 16px;
  height: 16px;
  transition: transform var(--transition);
}

.case-nav-back:hover svg {
  transform: translateX(-3px);
}

.case-nav-title {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-text-muted);
}

/* ========== Hero 区域（深色背景） ========== */
.case-hero {
  padding: 160px 0 80px;
  background-color: #1a1c1c;
  background-image: radial-gradient(circle, rgba(255, 255, 255, 0.07) 1px, transparent 1px);
  background-size: 32px 32px;
  background-position: center center;
  color: var(--color-on-primary);
  overflow: hidden;
  position: relative;
}

.case-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 70% 60% at 50% 45%, transparent 30%, #1a1c1c 75%);
  pointer-events: none;
  z-index: 0;
}

.case-hero .container {
  text-align: center;
  position: relative;
  z-index: 1;
}

.case-hero-badges {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.case-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: 100px;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.case-badge--role {
  background: rgba(255, 255, 255, 0.15);
  color: rgba(255, 255, 255, 0.9);
}

.case-badge--tech {
  background: rgba(199, 234, 222, 0.12);
  color: #a8d5c8;
}

.case-hero-title {
  font-family: var(--font-serif);
  font-size: 3.5rem;
  font-weight: 400;
  font-style: italic;
  line-height: 1.2;
  margin-bottom: 16px;
  color: #ffffff;
}

.case-hero-subtitle {
  font-size: 1.15rem;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.75);
  max-width: 640px;
  margin: 0 auto 48px;
}

/* 指标卡片行 */
.metric-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  max-width: 800px;
  margin: 0 auto 56px;
}

.metric-card {
  text-align: center;
  padding: 24px 16px;
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.metric-value {
  font-family: var(--font-serif);
  font-size: 2rem;
  font-weight: 700;
  color: #ffffff;
  line-height: 1.2;
  margin-bottom: 6px;
}

.metric-label {
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.6);
  font-weight: 500;
}

/* Hero 展示图 */
.case-hero-image {
  max-width: 960px;
  margin: 0 auto;
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: 0 24px 64px rgba(0, 0, 0, 0.3);
}

.case-hero-image img {
  width: 100%;
  display: block;
}

.case-hero-image .image-placeholder {
  width: 100%;
  height: 480px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px dashed rgba(255, 255, 255, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(255, 255, 255, 0.3);
  font-size: 0.9rem;
}

/* 滚动提示 */
.scroll-indicator {
  margin-top: 48px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: rgba(255, 255, 255, 0.4);
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
}

.scroll-indicator-line {
  width: 1px;
  height: 32px;
  background: rgba(255, 255, 255, 0.2);
  animation: scrollPulse 2s ease-in-out infinite;
}

@keyframes scrollPulse {
  0%, 100% { opacity: 0.3; transform: scaleY(0.6); }
  50% { opacity: 1; transform: scaleY(1); }
}

/* ========== 通用 Section 样式 ========== */
.case-section {
  padding: 100px 0;
}

.case-section--alt {
  background: var(--color-surface);
}

/* 分行标题 */
.split-heading {
  font-family: var(--font-serif);
  font-size: 2.2rem;
  font-weight: 400;
  font-style: italic;
  line-height: 1.4;
  color: var(--color-text);
  margin-bottom: 56px;
}

.split-heading span {
  display: block;
}

/* ========== 背景与问题 ========== */
.target-user-card {
  background: var(--color-primary-light);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-xl);
  padding: 32px 40px;
  margin-bottom: 48px;
}

.target-user-card h3 {
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 12px;
  letter-spacing: 0.02em;
}

.target-user-card p {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--color-text-secondary);
}

.target-user-metrics {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  margin-top: 20px;
}

.target-user-metric {
  text-align: center;
  padding: 16px;
  background: var(--color-surface);
  border-radius: var(--radius-md);
}

.target-user-metric .metric-value {
  font-size: 1.5rem;
  color: var(--color-text);
}

.target-user-metric .metric-label {
  color: var(--color-text-muted);
}

/* 痛点卡片 */
.pain-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.pain-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-xl);
  padding: 32px;
  transition: var(--transition);
}

.pain-card:hover {
  border-color: var(--color-border);
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.pain-card-index {
  font-family: var(--font-serif);
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--color-border);
  line-height: 1;
  margin-bottom: 16px;
}

.pain-card h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--color-text);
}

.pain-card p {
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--color-text-secondary);
}

/* ========== 产品策略 ========== */
.phase-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.phase-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-xl);
  padding: 28px;
  transition: var(--transition);
}

.phase-card:hover {
  border-color: var(--color-border);
  box-shadow: var(--shadow-md);
}

.phase-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
}

.phase-label {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--color-text-muted);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.phase-status {
  display: inline-flex;
  padding: 3px 10px;
  border-radius: 100px;
  font-size: 0.7rem;
  font-weight: 600;
}

.phase-status--live {
  background: rgba(46, 125, 50, 0.1);
  color: #2e7d32;
}

.phase-status--planned {
  background: var(--color-surface-container);
  color: var(--color-text-muted);
}

.phase-card h3 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--color-text);
}

.phase-card ul {
  list-style: none;
  padding: 0;
}

.phase-card ul li {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  line-height: 1.7;
  padding-left: 16px;
  position: relative;
}

.phase-card ul li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 10px;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--color-border);
}

/* ========== 核心功能（交替布局） ========== */
.feature-block {
  display: flex;
  align-items: center;
  gap: 64px;
  margin-bottom: 80px;
}

.feature-block:last-child {
  margin-bottom: 0;
}

.feature-block--reverse {
  flex-direction: row-reverse;
}

.feature-image {
  flex: 1;
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

.feature-image img {
  width: 100%;
  display: block;
}

.feature-image .image-placeholder {
  width: 100%;
  height: 320px;
  background: var(--color-surface-container);
  border: 1px dashed var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-muted);
  font-size: 0.85rem;
}

.feature-content {
  flex: 1;
}

.feature-index {
  font-family: var(--font-serif);
  font-size: 3rem;
  font-weight: 700;
  color: var(--color-border);
  line-height: 1;
  margin-bottom: 16px;
}

.feature-content h3 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--color-text);
}

.feature-content > p {
  font-size: 0.95rem;
  line-height: 1.8;
  color: var(--color-text-secondary);
  margin-bottom: 24px;
}

/* 设计决策引用块 */
.design-decision {
  background: var(--color-primary-light);
  border-left: 3px solid var(--color-primary);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: 20px 24px;
}

.design-decision-label {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: 8px;
}

.design-decision p {
  font-size: 0.85rem;
  line-height: 1.7;
  color: var(--color-text-secondary);
}

/* ========== 关键挑战 ========== */
.challenge-block {
  margin-bottom: 56px;
}

.challenge-block:last-child {
  margin-bottom: 0;
}

.challenge-header {
  display: flex;
  align-items: baseline;
  gap: 16px;
  margin-bottom: 24px;
}

.challenge-index {
  font-family: var(--font-serif);
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-border);
  line-height: 1;
}

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

/* 演进流程 */
.challenge-flow {
  display: flex;
  align-items: stretch;
  gap: 0;
}

.challenge-step {
  flex: 1;
  background: var(--color-card-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-xl);
  padding: 28px;
}

.challenge-step h4 {
  font-size: 0.9rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--color-text);
}

.challenge-step .step-metric {
  font-family: var(--font-serif);
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 8px;
}

.challenge-step p {
  font-size: 0.85rem;
  line-height: 1.7;
  color: var(--color-text-secondary);
}

.challenge-arrow {
  display: flex;
  align-items: center;
  padding: 0 16px;
  font-size: 1.5rem;
  color: var(--color-text-muted);
}

/* VS 布局 */
.challenge-vs {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 0;
  align-items: stretch;
}

.challenge-vs-side {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-xl);
  padding: 28px;
}

.challenge-vs-divider {
  display: flex;
  align-items: center;
  padding: 0 20px;
  font-size: 1rem;
  font-weight: 800;
  color: var(--color-text-muted);
  letter-spacing: 0.05em;
}

.challenge-resolution {
  margin-top: 20px;
  background: var(--color-primary-light);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-xl);
  padding: 24px 32px;
}

.challenge-resolution h4 {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 8px;
}

.challenge-resolution p {
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--color-text-secondary);
}

/* ========== 项目成果 ========== */
.result-section {
  padding: 100px 0;
  background-color: #1a1c1c;
  background-image: radial-gradient(circle, rgba(255, 255, 255, 0.07) 1px, transparent 1px);
  background-size: 32px 32px;
  background-position: center center;
  color: var(--color-on-primary);
  position: relative;
}

.result-section::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 70% 60% at 50% 50%, transparent 30%, #1a1c1c 75%);
  pointer-events: none;
  z-index: 0;
}

.result-section .container {
  position: relative;
  z-index: 1;
}

.result-heading {
  font-family: var(--font-serif);
  font-size: 2.2rem;
  font-weight: 400;
  font-style: italic;
  color: #ffffff;
  margin-bottom: 56px;
}

.result-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  max-width: 900px;
}

.result-card {
  padding: 32px;
  border-radius: var(--radius-xl);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.result-value {
  font-family: var(--font-serif);
  font-size: 2.2rem;
  font-weight: 700;
  color: #ffffff;
  line-height: 1.2;
  margin-bottom: 8px;
}

.result-label {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.6);
  font-weight: 500;
  line-height: 1.5;
}

/* ========== 底部项目导航 ========== */
.case-footer-nav {
  padding: 48px 0;
  border-top: 1px solid var(--color-border-light);
}

.case-footer-nav .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.case-footer-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: var(--transition);
}

.case-footer-link:hover {
  color: var(--color-primary);
}

.case-footer-link svg {
  width: 16px;
  height: 16px;
  transition: transform var(--transition);
}

.case-footer-link--prev:hover svg {
  transform: translateX(-3px);
}

.case-footer-link--next:hover svg {
  transform: translateX(3px);
}

.case-footer-link--next {
  flex-direction: row;
}

.case-footer-next-info {
  text-align: right;
}

.case-footer-next-label {
  display: block;
  font-size: 0.75rem;
  color: var(--color-text-muted);
  font-weight: 500;
  margin-bottom: 2px;
}

/* ========== 响应式 ========== */
@media (max-width: 1024px) {
  .case-hero-title {
    font-size: 2.8rem;
  }

  .metric-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .pain-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .phase-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .feature-block,
  .feature-block--reverse {
    flex-direction: column;
    gap: 32px;
  }

  .split-heading {
    font-size: 1.8rem;
  }
}

@media (max-width: 768px) {
  .case-hero {
    padding: 120px 0 60px;
  }

  .case-hero-title {
    font-size: 2.2rem;
  }

  .case-hero-subtitle {
    font-size: 1rem;
  }

  .metric-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
  }

  .metric-card {
    padding: 16px 12px;
  }

  .metric-value {
    font-size: 1.5rem;
  }

  .pain-grid {
    grid-template-columns: 1fr;
  }

  .phase-grid {
    grid-template-columns: 1fr;
  }

  .split-heading {
    font-size: 1.6rem;
  }

  .case-section {
    padding: 64px 0;
  }

  .challenge-flow {
    flex-direction: column;
    gap: 12px;
  }

  .challenge-arrow {
    justify-content: center;
    padding: 8px 0;
    transform: rotate(90deg);
  }

  .challenge-vs {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .challenge-vs-divider {
    justify-content: center;
    padding: 8px 0;
  }

  .result-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .result-section {
    padding: 64px 0;
  }

  .result-heading {
    font-size: 1.8rem;
  }

  .case-hero-image .image-placeholder {
    height: 280px;
  }

  .case-footer-nav .container {
    flex-direction: column;
    gap: 24px;
    align-items: flex-start;
  }

  .case-footer-next-info {
    text-align: left;
  }

  .target-user-card {
    padding: 24px;
  }

  .target-user-metrics {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  .case-hero-title {
    font-size: 1.8rem;
  }

  .case-hero-badges {
    gap: 8px;
  }

  .case-badge {
    font-size: 0.7rem;
    padding: 4px 10px;
  }

  .metric-grid {
    grid-template-columns: 1fr 1fr;
  }

  .metric-value {
    font-size: 1.3rem;
  }

  .feature-image .image-placeholder {
    height: 200px;
  }

  .result-grid {
    grid-template-columns: 1fr;
  }

  .result-value {
    font-size: 1.8rem;
  }

  .pain-card,
  .phase-card {
    padding: 24px;
  }
}