/* KOC.TOP 现代风格样式 - Next.js/Bilibili/YouTube 风格 */
:root {
  --bg: #ffffff;
  --bg-secondary: #f8f9fa;
  --bg-tertiary: #f1f3f5;
  --surface: #ffffff;
  --border: #e9ecef;
  --border-hover: #dee2e6;
  --text-primary: #212529;
  --text-secondary: #6c757d;
  --text-muted: #adb5bd;
  --accent: #2563eb;
  --accent-hover: #1d4ed8;
  --accent-light: #eff6ff;
  --success: #10b981;
  --radius: 8px;
  --radius-sm: 6px;
  --radius-lg: 12px;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html,
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";
  background: var(--bg);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: inherit;
  text-decoration: none;
  transition: var(--transition);
}

a:hover {
  color: var(--accent);
}

/* 导航栏 - 现代扁平风格 */
.nav-main {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 0.75rem 0;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

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

.brand {
  display: flex;
  align-items: center;
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.brand-logo {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
  display: block;
}

.brand-label {
  font-weight: 700;
  letter-spacing: 0.02em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.nav-link {
  color: var(--text-secondary);
  font-weight: 500;
  font-size: 0.9375rem;
  padding: 0.5rem 0.75rem;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.nav-link:hover {
  color: var(--text-primary);
  background: var(--bg-secondary);
}

.nav-divider {
  width: 1px;
  height: 20px;
  background: var(--border);
  margin: 0 0.5rem;
}

/* 按钮 - 现代扁平风格 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.625rem 1.25rem;
  font-weight: 500;
  font-size: 0.9375rem;
  border-radius: var(--radius);
  border: none;
  cursor: pointer;
  transition: var(--transition);
  white-space: nowrap;
  line-height: 1.5;
  font-family: inherit;
}

.btn-primary {
  background: var(--accent);
  color: white;
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  background: var(--accent-hover);
  color: white;
  box-shadow: var(--shadow);
  transform: translateY(-1px);
}

.btn-secondary {
  background: var(--success);
  color: white;
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background: #059669;
  color: white;
  box-shadow: var(--shadow);
  transform: translateY(-1px);
}

.btn-accent {
  background: var(--accent);
  color: white;
  box-shadow: var(--shadow-sm);
}

.btn-accent:hover {
  color: white;
  box-shadow: var(--shadow);
  transform: translateY(-1px);
}

.btn-surface {
  background: var(--surface);
  color: var(--text-primary);
  border: 1px solid var(--border);
}

.btn-surface:hover {
  background: var(--bg-secondary);
  border-color: var(--border-hover);
}

.btn-outline {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid var(--border);
}

.btn-outline:hover {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border-color: var(--accent);
}

.btn-pill {
  border-radius: 999px;
  padding: 0.5rem 1rem;
}

.btn-theme {
  background: var(--surface);
  color: var(--text-secondary);
  border: 1px solid var(--border);
}

.btn-theme:hover {
  background: var(--bg-secondary);
  color: var(--text-primary);
}

.btn-sm {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

/* 内容区域 */
.content-wrapper {
  padding: 2rem 0 4rem;
  min-height: calc(100vh - 80px);
}

.site-shell {
  max-width: 1200px;
}

.section {
  margin-bottom: 4rem;
}

.section-block {
  background: var(--surface);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
}

/* 面包屑 */
.trail {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 0.75rem 1.25rem;
  margin-bottom: 1.5rem;
  border: 1px solid var(--border);
  display: inline-block;
}

.breadcrumb {
  background: transparent;
  padding: 0;
  margin: 0;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.breadcrumb-item {
  color: var(--text-secondary);
  font-size: 0.875rem;
}

.breadcrumb-item.active {
  color: var(--text-primary);
}

.breadcrumb-item + .breadcrumb-item::before {
  content: "/";
  color: var(--text-muted);
  margin-right: 0.5rem;
}

/* 促销条 */
.promo-strip {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--accent-light);
  border-radius: var(--radius);
  padding: 1rem 1.5rem;
  margin-bottom: 2rem;
  border: 1px solid rgba(37, 99, 235, 0.2);
}

.promo-info {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--text-primary);
  font-weight: 500;
  font-size: 0.9375rem;
}

.promo-info i {
  color: var(--accent);
}

/* Hero 区域 */
.hero-block {
  background: var(--surface);
  border-radius: var(--radius-lg);
  padding: 3rem;
  margin-bottom: 3rem;
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
}

.hero-title {
  font-size: 2.25rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 1rem;
  color: var(--text-primary);
  letter-spacing: -0.03em;
}

.hero-highlight {
  background: linear-gradient(135deg, var(--accent), #3b82f6);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-lead {
  font-size: 1.0625rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
  line-height: 1.7;
  font-weight: 400;
}

/* 表单 */
.form-shell {
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  padding: 2rem;
  border: 1px solid var(--border);
  margin-bottom: 1.5rem;
}

.form-label {
  display: block;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.75rem;
  font-size: 0.9375rem;
}

.form-label.muted {
  color: var(--text-secondary);
  font-weight: 500;
}

.form-control {
  width: 100%;
  padding: 0.875rem 1rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-primary);
  font-size: 0.9375rem;
  transition: var(--transition);
  font-family: inherit;
}

.form-control:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-control::placeholder {
  color: var(--text-muted);
}

.form-label-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.75rem;
}

.form-link {
  color: var(--accent);
  font-size: 0.875rem;
  font-weight: 500;
}

.form-link:hover {
  color: var(--accent-hover);
}

.input-wrapper {
  position: relative;
}

.char-count {
  position: absolute;
  right: 0.75rem;
  top: 50%;
  transform: translateY(-50%);
  font-size: 0.8125rem;
  color: var(--text-muted);
  pointer-events: none;
}

.form-hint {
  display: block;
  margin-top: 0.5rem;
  font-size: 0.8125rem;
  color: var(--text-muted);
}

.btn-lg {
  padding: 0.875rem 2rem;
  font-size: 1rem;
  width: 100%;
}

/* 平台选择按钮 - 现代风格 */
.platform-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1rem;
}

.platform-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.625rem;
  padding: 0.75rem 1rem;
  background: var(--surface);
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  transition: var(--transition);
  font-size: 0.9375rem;
  color: var(--text-secondary);
  font-weight: 500;
  position: relative;
}

.platform-chip:hover {
  background: var(--bg-secondary);
  border-color: var(--border-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

.platform-chip input {
  display: none;
}

.platform-chip input:checked ~ span {
  color: var(--text-primary);
}

.platform-chip:has(input:checked) {
  background: var(--accent-light);
  border-color: var(--accent);
  color: var(--accent);
}

.platform-chip:has(input:checked) .platform-logo {
  opacity: 1;
  transform: scale(1);
}

.platform-chip:has(input:checked)::after {
  content: "✓";
  position: absolute;
  top: -6px;
  right: -6px;
  width: 20px;
  height: 20px;
  background: var(--accent);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  font-weight: 700;
  box-shadow: var(--shadow-sm);
}

.platform-logo {
  width: 24px;
  height: 24px;
  border-radius: var(--radius-sm);
  object-fit: cover;
  flex-shrink: 0;
  transition: var(--transition);
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.badge-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1.5rem;
}

.badge-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 0.875rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 0.8125rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.badge-chip i {
  color: var(--accent);
}

/* 统计卡片 - 横向一行 */
.stat-row {
  display: flex;
  gap: 1rem;
  margin-top: 2rem;
  flex-wrap: wrap;
}

.stat-card {
  background: var(--surface);
  border-radius: var(--radius-lg);
  padding: 1.25rem 1.5rem;
  border: 1px solid var(--border);
  text-align: center;
  transition: var(--transition);
  flex: 1;
  min-width: 140px;
}

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

.stat-value {
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--accent);
  margin-bottom: 0.5rem;
  line-height: 1;
}

.stat-label {
  font-size: 0.8125rem;
  color: var(--text-secondary);
  font-weight: 500;
  line-height: 1.4;
}

.note {
  display: block;
  margin-top: 1rem;
  color: var(--text-muted);
  font-size: 0.8125rem;
}

/* 章节标题 */
.section-heading {
  margin-bottom: 2rem;
}

.eyebrow {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent);
  margin-bottom: 0.75rem;
}

.section-heading h2 {
  font-size: 1.875rem;
  font-weight: 800;
  margin-bottom: 0.75rem;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.section-heading p {
  color: var(--text-secondary);
  font-size: 1.0625rem;
  line-height: 1.7;
}

/* 功能卡片 */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.feature-card {
  background: var(--surface);
  border-radius: var(--radius-lg);
  padding: 2rem;
  border: 1px solid var(--border);
  transition: var(--transition);
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--border-hover);
}

.feature-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 1.25rem;
  background: var(--bg-secondary);
}

.feature-card.tone-green .feature-icon {
  background: rgba(16, 185, 129, 0.1);
  color: var(--success);
}

.feature-card.tone-blue .feature-icon {
  background: rgba(37, 99, 235, 0.1);
  color: var(--accent);
}

.feature-card.tone-orange .feature-icon {
  background: rgba(245, 158, 11, 0.1);
  color: #f59e0b;
}

.feature-card h5 {
  font-size: 1.125rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: var(--text-primary);
}

.feature-card p {
  color: var(--text-secondary);
  line-height: 1.7;
  margin: 0;
}

/* 解决方案板块 */
.solution-board {
  background: var(--surface);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
}

.board-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 2rem;
  flex-wrap: wrap;
  gap: 1rem;
}

.solution-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.solution-card {
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  border: 1px solid var(--border);
  transition: var(--transition);
}

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

.solution-card h6 {
  font-size: 1.0625rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.solution-card h6 i {
  color: var(--accent);
}

.solution-card p {
  color: var(--text-secondary);
  margin: 0;
  line-height: 1.7;
}

/* 资源卡片 */
.resource-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
}

.resource-card {
  background: var(--surface);
  border-radius: var(--radius-lg);
  padding: 2rem;
  border: 1px solid var(--border);
  display: flex;
  gap: 1.5rem;
  transition: var(--transition);
}

.resource-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  border-color: var(--border-hover);
}

.resource-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius);
  background: var(--bg-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  color: var(--accent);
  flex-shrink: 0;
}

.resource-body h5 {
  font-size: 1.125rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: var(--text-primary);
}

.resource-body p {
  color: var(--text-secondary);
  margin-bottom: 1rem;
  line-height: 1.7;
}

.link-arrow {
  color: var(--accent);
  font-weight: 600;
  font-size: 0.9375rem;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.link-arrow:hover {
  color: var(--accent-hover);
}

.link-arrow::after {
  content: "→";
  transition: transform 0.2s ease;
}

.link-arrow:hover::after {
  transform: translateX(4px);
}

/* 页脚 */
.footer-main {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  padding: 2.5rem 0;
  margin-top: 4rem;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.footer-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.footer-note {
  color: var(--text-secondary);
  font-size: 0.875rem;
  margin: 0;
}

.footer-beian {
  color: var(--text-muted);
  font-size: 0.8125rem;
}

.footer-beian a {
  color: var(--text-muted);
  transition: var(--transition);
}

.footer-beian a:hover {
  color: var(--text-secondary);
}

.footer-links {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.footer-links a {
  color: var(--text-secondary);
  font-size: 0.875rem;
  transition: var(--transition);
}

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

/* 移动端条 */
.mobile-strip {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: var(--surface);
  border-top: 1px solid var(--border);
  padding: 1rem;
  z-index: 1000;
  box-shadow: 0 -4px 6px -1px rgba(0, 0, 0, 0.1);
}

/* 深色模式 - 优化为更亮的深色 */
body.dark-mode {
  --bg: #1a1a1f;
  --bg-secondary: #242429;
  --bg-tertiary: #2d2d35;
  --surface: #242429;
  --border: #3a3a42;
  --border-hover: #484851;
  --text-primary: #ffffff;
  --text-secondary: #b4b4c0;
  --text-muted: #8a8a95;
  --accent: #3b82f6;
  --accent-hover: #2563eb;
  --accent-light: rgba(59, 130, 246, 0.15);
}

/* 响应式 */
@media (max-width: 767.98px) {
  .hero-title {
    font-size: 1.75rem;
  }

  .hero-block {
    padding: 2rem 1.5rem;
  }

  .form-shell {
    padding: 1.5rem;
  }

  .section-block,
  .solution-board {
    padding: 2rem 1.5rem;
  }

  .stat-row {
    flex-direction: column;
  }

  .stat-card {
    min-width: 100%;
  }

  .board-head {
    flex-direction: column;
  }

  .footer-inner {
    flex-direction: column;
  }

  .platform-list {
    gap: 0.5rem;
  }

  .platform-chip {
    padding: 0.625rem 0.875rem;
    font-size: 0.875rem;
  }
}

@media (min-width: 768px) {
  .mobile-strip {
    display: none;
  }
}