/* ============================================================
   2810unsheathe.com — 共享基础样式（苹果官网风格）
   桌面版 v1.1.0
   ============================================================ */

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

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro SC", "SF Pro Text",
    "SF Pro Display", "PingFang SC", "Helvetica Neue", "Hiragino Sans GB",
    "Microsoft YaHei", sans-serif;
  color: #1d1d1f;
  background: #fff;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  text-size-adjust: 100%;
}

a { color: inherit; text-decoration: none; }
img { display: block; }
button { font-family: inherit; cursor: pointer; background: none; border: none; color: inherit; }
ul { list-style: none; }

/* ------------------------------------------------------------
   顶部菜单栏（吸顶毛玻璃；子菜单为全宽面板，展开时内容页盖毛玻璃）
   ------------------------------------------------------------ */

.site-nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: rgba(245, 245, 247, 0.96); /* 1.0.1：与子菜单相同的白色 */
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 4.5px solid #81d8d0; /* v1.1.6：菜单栏底部主色边线；v1.1.7 ÷2→3px；v1.1.9 再加粗至 6 与 3 之间（4.5px） */
}

.nav-inner {
  max-width: 1024px;
  margin: 0 auto;
  height: 44px;
  padding: 0 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 4px;
}

.nav-item {
  position: relative;
  height: 44px;
  display: flex;
  align-items: center;
  flex: 0 0 auto;
}

.nav-link {
  font-size: 12px;
  color: rgba(0, 0, 0, 0.8);
  letter-spacing: 0.01em;
  padding: 0 5px;
  white-space: nowrap;
  transition: color 0.2s ease;
}

/* 1.0.5：悬停不改变文字颜色 */

/* v1.1.0：导航左侧 logo —— 用黑色图形 + CSS mask 实现“悬停变 #8C2828” */
.nav-logo .nav-link {
  display: flex;
  align-items: center;
  padding: 0 5px;
}

.nav-logo-mark {
  display: block;
  width: 36px;
  height: 36px;
  background-color: #000;   /* 默认黑色 */
  -webkit-mask: url("../logo_black.png") center / contain no-repeat;
  mask: url("../logo_black.png") center / contain no-repeat;
  transition: background-color 0.2s ease;
}

.nav-logo a:hover .nav-logo-mark,
.nav-logo a:focus-visible .nav-logo-mark {
  background-color: #81d8d0;   /* v1.1.4：悬停变主色 #81d8d0（原 #8C2828），离开恢复 */
}

/* --- 搜索（1.0.4：面板与子菜单同款全宽；此处的 .search-* 均为面板内样式） --- */
.nav-search-btn {
  display: flex;
  align-items: center;
  gap: 5px;
  font-size: 12px;
  color: rgba(0, 0, 0, 0.8);
  padding: 0 5px;
  transition: color 0.2s ease;
}

/* 1.0.5：悬停不改变文字颜色 */
.nav-search-btn svg { display: block; }

.search-row {
  display: flex;
  align-items: center;
  gap: 12px;
}

.search-icon { display: flex; color: #86868b; }

.search-input {
  /* 1.0.6 追加：仿苹果“取消搜索框”——无边框无底色，
     与子菜单背景同色融为一体 */
  background: transparent;
  border: none;
  border-radius: 0;
  padding: 6px 2px;
  font-size: 17px;
  font-family: inherit;
  color: #1d1d1f;
  outline: none;
  caret-color: #06c;
}

.search-input-lg { width: min(480px, 46vw); }

.search-input::placeholder { color: #86868b; }

.search-hint {
  display: none;
  font-size: 12px;
  color: #86868b;
  margin: 12px 2px 0;
  text-align: left;
}

.search-hint.show { display: block; }

/* --- 内容页毛玻璃遮罩（子菜单展开期间，菜单栏以下被盖住） --- */
#navMask {
  position: fixed;
  top: 44px;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 91;
  background: rgba(255, 255, 255, 0.14);
  -webkit-backdrop-filter: blur(18px) saturate(140%);
  backdrop-filter: blur(18px) saturate(140%);
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease;
}

#navMask.show { opacity: 1; visibility: visible; }

/* --- 全宽子菜单层（宽度 = 网页宽度，仿苹果官网） --- */
#navLayer {
  position: fixed;
  top: 44px;
  left: 0;
  right: 0;
  z-index: 93;
  pointer-events: none;
  visibility: hidden;
}

#navLayer.show { pointer-events: auto; visibility: visible; }

.nav-pop-wide {
  /* 1.0.1：所有子菜单统一定位在层顶部 → 都紧贴菜单栏同一位置
     1.0.5：未展开的面板 visibility:hidden + pointer-events:none，
     不会遮挡/吃掉其它展开面板的点击（修复“有的按钮点不动”） */
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  pointer-events: none;
  visibility: hidden;
  background: rgba(245, 245, 247, 0.96);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
  box-shadow: 0 18px 40px rgba(0, 0, 0, 0.16);
  border-radius: 0;            /* 1.0.5：直角矩形 */
  overflow: hidden;
  opacity: 0;
  transform: translateY(-8px);
  transition: opacity 0.22s ease, transform 0.22s ease,
    visibility 0s linear 0.22s;
}

.nav-pop-wide.open {
  opacity: 1;
  transform: translateY(0);
  visibility: visible;
  pointer-events: auto;
  transition: opacity 0.22s ease, transform 0.22s ease, visibility 0s;
}

.nav-pop-inner {
  max-width: none;           /* 1.0.1：面板内容直接铺满整宽，便于 1/5 分线对齐 */
  padding: 22px 0 30px;
}

.nav-pop-col {
  width: max-content;
  min-width: 150px;
  margin-left: 20vw;         /* 1.0.1：子项目对齐至子菜单宽度的 1/5 分线 */
}

.nav-sublink {
  display: block;
  font-size: 19.5px;      /* 1.0.2：为 1.0.1 的 39px 的 0.5 倍 */
  font-weight: 700;       /* 1.0.1：加粗 */
  color: #1d1d1f;
  letter-spacing: -0.01em;
  line-height: 1.5;
  padding: 3px 10px;
  white-space: nowrap;
}

/* v1.1.5：子项目悬停 → 文本正下方滑出主色衬线
   进入：从左向右展开（scaleX 0→1，原点在左）
   离开：从右向左收起（scaleX 1→0，右端先收回） */
.sl-txt {
  position: relative;
  display: inline-block;
  padding-bottom: 2px;
}

.sl-txt::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;            /* 衬线长度 = 该子项目文本宽度 */
  height: 3px;
  background-color: #81d8d0;
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.35s ease;
}

.nav-sublink:hover .sl-txt::after,
.nav-sublink:focus-visible .sl-txt::after {
  transform: scaleX(1);
}

/* ------------------------------------------------------------
   子页面（1.0.4：纯文本"开发中，敬请期待"，垂直居中）
   ------------------------------------------------------------ */

body.pad { padding-top: 44px; }

.page-dev {
  min-height: calc(100vh - 44px);
  display: flex;
  align-items: center;
  justify-content: center;
}

.page-dev p {
  font-size: 17px;
  color: #1d1d1f;
  letter-spacing: 0.01em;
}

/* ------------------------------------------------------------
   窄屏收起式菜单（1.0.6，≤900px 仿苹果：= / X + 全屏菜单）
   ------------------------------------------------------------ */

.nav-actions {
  display: flex;
  align-items: center;
}

.nav-toggle-item { display: none; }

.nav-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 44px;
  color: rgba(0, 0, 0, 0.8);
}

.nav-toggle svg { display: block; }
.nav-toggle .ico-close { display: none; }
.nav-toggle.open .ico-burger { display: none; }
.nav-toggle.open .ico-close { display: block; }

/* 全屏菜单（覆盖菜单栏以下全部区域，只列主项目） */
#navFullscreen {
  position: fixed;
  top: 44px;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 95;
  background: rgba(245, 245, 247, 0.98);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
  overflow-y: auto;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-6px);
  transition: opacity 0.25s ease, transform 0.25s ease, visibility 0s linear 0.25s;
}

#navFullscreen.open {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
  transition: opacity 0.25s ease, transform 0.25s ease, visibility 0s;
}

.fs-inner {
  padding: 26px max(24px, 6vw) 90px;
}

.fs-link {
  display: block;
  font-size: 19.5px;   /* 与子菜单同款字号 */
  font-weight: 700;    /* 与子菜单同款加粗 */
  color: #1d1d1f;
  padding: 14px 0;
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
  transition: color 0.2s ease; /* 悬停/点击不变色 */
}

html.fs-lock,
html.fs-lock body { overflow: hidden; }

/* 手机动态视口高度（1.0.6，有 100vh 兜底） */
@supports (min-height: 100dvh) {
  .page-dev { min-height: calc(100dvh - 44px); }
}

/* 窄屏（≤900px）：主项目收起，显示 = 按钮 */
@media (max-width: 900px) {
  .nav-main { display: none !important; }
  .nav-toggle-item { display: flex; }
  .nav-search-btn span { display: none; }  /* 搜索只留图标 */
  .nav-search-btn { padding: 0 10px; }
  .nav-logo-mark { width: 36px; height: 36px; }  /* v1.1.0：窄屏 logo 尺寸与桌面一致（36px） */
  /* 1.0.6 追加：窄屏搜索与 = 集合图标放大 1.4 倍 */
  .nav-search-btn svg { width: 17px; height: 17px; }  /* 12 × 1.4 ≈ 17 */
  .nav-toggle svg { width: 22px; height: 22px; }       /* 16 × 1.4 ≈ 22 */
  .site-nav { border-bottom-width: 3px; }  /* v1.1.9：手机端主色边线 4 与 2 之间（3px） */
  * { -webkit-tap-highlight-color: transparent; }
}

/* 尊重系统“减弱动态效果”设置 */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { animation-duration: 0.001s !important; transition-duration: 0.001s !important; }
}