/* ==========================================================================
   宝贝云 (bbyvpn.homes) - 官方网站核心样式
   框架：第83号 樱花校园 · 日式手账留白 · 飘落樱花与笔记本式排版
   ========================================================================== */

:root {
  /* 樱花粉色系与校园日系色彩 */
  --sakura-50: #FFF7F9;
  --sakura-100: #FFEAF0;
  --sakura-200: #FFD4E0;
  --sakura-300: #FFB8CB;
  --sakura-400: #FF8EA9;
  --sakura-500: #FF6584;
  --sakura-600: #E63968;
  --sakura-700: #B81844;

  /* 抹茶青芽绿 & 学府深蓝点缀 */
  --matcha-500: #40916C;
  --matcha-100: #D8F3DC;
  --campus-navy: #1D3557;

  /* 墨黑与质感文字 */
  --ink-900: #1F2232;
  --ink-800: #2D3142;
  --ink-700: #4F5D75;
  --ink-500: #788599;
  --ink-300: #BFC0C0;

  /* 日式手账和纸与留白质感底色 */
  --paper-bg: #FCF9FA;
  --paper-ruled: #F5EAEF;
  --card-bg: #FFFFFF;
  --border-soft: #F0DEE5;
  --border-accent: #FFB8CB;

  /* 阴影体系 */
  --shadow-sm: 0 2px 8px rgba(230, 57, 104, 0.04);
  --shadow-md: 0 8px 24px rgba(230, 57, 104, 0.08);
  --shadow-lg: 0 16px 40px rgba(230, 57, 104, 0.12);
  --shadow-card: 0 10px 30px rgba(45, 49, 66, 0.05);

  /* 尺寸与圆角 */
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-pill: 9999px;

  /* 顶部导航高度与偏移量 */
  --nav-height: 74px;
}

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

html {
  font-family: -apple-system, BlinkMacSystemFont, "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.68;
  color: var(--ink-800);
  background-color: var(--paper-bg);
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  position: relative;
  min-height: 100vh;
  overflow-x: hidden;
  background-color: var(--paper-bg);
}

/* 锚点导航偏移保护 */
[id] {
  scroll-margin-top: calc(var(--nav-height) + 24px);
}

a {
  color: inherit;
  text-decoration: none;
  transition: all 0.25s ease;
}

img, svg {
  display: block;
  max-width: 100%;
}

button, input, textarea {
  font-family: inherit;
  font-size: inherit;
  outline: none;
  border: none;
}

button {
  cursor: pointer;
  background: transparent;
}

ul, ol {
  list-style: none;
}

.container {
  width: 100%;
  max-width: 1200px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

/* 顶部固定导航栏 */
.site-header {
  position: sticky;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--nav-height);
  z-index: 1000;
  background: rgba(252, 249, 250, 0.88);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-soft);
  transition: all 0.3s ease;
}

.site-header.scrolled {
  background: rgba(255, 255, 255, 0.94);
  box-shadow: 0 4px 20px rgba(230, 57, 104, 0.08);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.brand-link {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-logo-img {
  height: 44px;
  width: auto;
  transition: transform 0.3s ease;
}

.brand-link:hover .brand-logo-img {
  transform: scale(1.03) rotate(-1deg);
}

/* 桌面端导航 */
.nav-menu {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--ink-700);
  position: relative;
  padding: 6px 0;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--sakura-400), var(--sakura-600));
  border-radius: 2px;
  transition: width 0.3s ease;
}

.nav-link:hover {
  color: var(--sakura-600);
}

.nav-link:hover::after {
  width: 100%;
}

/* 核心 CTA 统一按钮规范 */
.btn-primary-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 24px;
  background: linear-gradient(135deg, var(--sakura-500) 0%, var(--sakura-600) 100%);
  color: #FFFFFF !important;
  font-weight: 600;
  font-size: 0.96rem;
  border-radius: var(--radius-pill);
  box-shadow: 0 6px 18px rgba(230, 57, 104, 0.28);
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.15);
}

.btn-primary-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 24px rgba(230, 57, 104, 0.38);
  background: linear-gradient(135deg, var(--sakura-400) 0%, var(--sakura-600) 100%);
}

.btn-primary-cta:active {
  transform: translateY(0);
}

.btn-secondary-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 24px;
  background: #FFFFFF;
  color: var(--ink-800);
  font-weight: 600;
  font-size: 0.96rem;
  border-radius: var(--radius-pill);
  border: 1.5px solid var(--border-accent);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.03);
  transition: all 0.25s ease;
}

.btn-secondary-cta:hover {
  border-color: var(--sakura-500);
  color: var(--sakura-600);
  background: var(--sakura-50);
  transform: translateY(-2px);
}

/* 手机端汉堡菜单按钮 */
.mobile-toggle-btn {
  display: none;
  flex-direction: column;
  justify-content: space-around;
  width: 32px;
  height: 32px;
  padding: 4px;
  z-index: 1010;
}

.mobile-toggle-btn span {
  width: 100%;
  height: 2.5px;
  background-color: var(--ink-800);
  border-radius: 2px;
  transition: all 0.3s ease;
}

.mobile-toggle-btn.open span:nth-child(1) {
  transform: translateY(8px) rotate(45deg);
}

.mobile-toggle-btn.open span:nth-child(2) {
  opacity: 0;
}

.mobile-toggle-btn.open span:nth-child(3) {
  transform: translateY(-8px) rotate(-45deg);
}

/* 移动端侧滑抽屉 */
.mobile-drawer {
  position: fixed;
  top: 0;
  right: -100%;
  width: 82%;
  max-width: 360px;
  height: 100vh;
  background: #FFFFFF;
  box-shadow: -8px 0 24px rgba(0, 0, 0, 0.12);
  z-index: 1005;
  display: flex;
  flex-direction: column;
  padding: 88px 28px 40px;
  transition: right 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  overflow-y: auto;
}

.mobile-drawer.active {
  right: 0;
}

.mobile-drawer-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.4);
  backdrop-filter: blur(4px);
  z-index: 1004;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease;
}

.mobile-drawer-overlay.active {
  opacity: 1;
  pointer-events: auto;
}

.mobile-drawer .nav-link {
  font-size: 1.1rem;
  padding: 14px 0;
  border-bottom: 1px dashed var(--border-soft);
  display: block;
}

.mobile-drawer .btn-primary-cta {
  margin-top: 24px;
  width: 100%;
}

/* 响应式断点 */
@media (max-width: 992px) {
  .nav-menu {
    display: none;
  }

  .header-cta-desktop {
    display: none;
  }

  .mobile-toggle-btn {
    display: flex;
  }
}