/* =============================================================================
   Chino's Blog — Navbar, mobile drawer, back-to-top, footer, scroll progress
   ============================================================================= */

/* ── Navbar (solid → glass on scroll) ────────────────────────── */
.navbar {
  position: sticky; top: 0; left: 0; right: 0;
  /* 高于 mobile-drawer(40)，使其顶部与抽屉重叠、视觉融为一体 */
  z-index: 45;
  width: 100%; display: flex; justify-content: center;
  transition: background var(--t-base), border-color var(--t-base), backdrop-filter var(--t-base), box-shadow var(--t-base);
  border-bottom: 1px solid transparent;
}
.navbar.is-scrolled {
  background: hsla(var(--surface), .85);
  backdrop-filter: blur(12px) saturate(1.4);
  -webkit-backdrop-filter: blur(12px) saturate(1.4);
  border-bottom-color: var(--color-divider-soft);
  box-shadow: 0 1px 3px hsla(0 0% 0% / .04);
}
.navbar-content {
  width: 100%; max-width: var(--content-w); margin-inline: auto;
  /* 移动端（菜单隐藏）：flex 两端对齐，品牌居左、操作居右。
     桌面端（≥768 菜单显示）：三栏网格「1fr · auto · 1fr」，
     菜单在内容宽度内绝对居中，与下方 hero/section 同宽一致。 */
  display: flex; align-items: center; justify-content: space-between;
  gap: var(--space-4); height: var(--nav-h); padding: 0 1rem;
}
.navbar-brand { flex-shrink: 0; }
.navbar-actions { flex-shrink: 0; }
@media (min-width: 768px) {
  .navbar-content { display: grid; grid-template-columns: 1fr auto 1fr; }
  .navbar-brand { justify-self: start; }
  .navbar-menu  { justify-self: center; }
  .navbar-actions { justify-self: end; }
}
@media (min-width: 1024px) { .navbar-content { padding: 0 2rem; } }

.navbar-brand {
  display: inline-flex; align-items: center; gap: .625rem;
  color: var(--color-foreground); font-family: var(--font-display);
  font-weight: 700; font-size: var(--fz-base); letter-spacing: -.01em; text-decoration: none;
}
.navbar-brand:hover { color: var(--color-foreground); }
.navbar-brand img {
  width: 2rem; height: 2rem; border-radius: var(--radius-md);
  object-fit: cover;
  transition: transform var(--t-spring);
}
.navbar-brand:hover img { transform: rotate(-6deg) scale(1.05); }
.navbar-brand-text {
  display: none;
  background: linear-gradient(135deg, hsl(var(--chino)) 0%, hsl(var(--ren)) 100%);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent; color: transparent;
}
@media (min-width: 640px) { .navbar-brand-text { display: inline; } }

.navbar-menu { display: none; align-items: center; gap: .125rem; }
@media (min-width: 768px) { .navbar-menu { display: flex; } }
.nav-link {
  position: relative; display: inline-flex; align-items: center; gap: .375rem;
  height: 2.25rem; padding: 0 .875rem; border-radius: var(--radius-lg);
  font-size: var(--fz-sm); font-weight: 500; color: var(--color-foreground);
  text-decoration: none; transition: background var(--t-fast), color var(--t-fast);
}
.nav-link svg { width: 1rem; height: 1rem; color: var(--color-muted); transition: color var(--t-fast); }
.nav-link:hover { background: var(--color-surface-2); color: var(--color-foreground); }
.nav-link:hover svg { color: var(--color-chino); }
.nav-link.is-active { background: hsla(var(--chino), .12); color: var(--color-chino); font-weight: 600; }
.nav-link.is-active svg { color: var(--color-chino); }
.nav-link.is-active::after {
  content: ''; position: absolute; left: 50%; bottom: -.375rem;
  width: 1.25rem; height: 2px; background: hsl(var(--chino)); transform: translateX(-50%);
  border-radius: 1px;
}

.navbar-actions { display: inline-flex; align-items: center; gap: .25rem; }

.search-box { position: relative; display: none; align-items: center; }
@media (min-width: 640px) { .search-box { display: flex; } }
.search-box .icon {
  position: absolute; left: .75rem; top: 50%; transform: translateY(-50%);
  width: 1rem; height: 1rem; color: var(--color-subtle); pointer-events: none;
}
.search-input {
  /* 固定宽度，聚焦时只变化边框/光环，不伸长，避免挤压布局偏移 */
  width: 11rem; height: 2.25rem; padding: 0 .75rem 0 2.25rem;
  border-radius: var(--radius-lg); background: var(--color-surface-2);
  border: 1px solid var(--color-border); color: var(--color-foreground);
  font-size: var(--fz-sm); transition: background var(--t-fast), border-color var(--t-fast), box-shadow var(--t-fast);
}
.search-input::placeholder { color: var(--color-placeholder); }
.search-input:hover { border-color: var(--color-border-strong); }
.search-input:focus {
  background: var(--color-surface);
  border-color: hsla(var(--chino), .4); box-shadow: 0 0 0 3px var(--color-ring);
}

.theme-toggle { position: relative; }
.theme-toggle .icon-sun, .theme-toggle .icon-moon { transition: transform var(--t-spring), opacity var(--t-base); }
html.chino-dark .theme-toggle .icon-sun  { transform: rotate(45deg) scale(.5); opacity: 0; }
html.chino-dark .theme-toggle .icon-moon { transform: none; opacity: 1; }
.theme-toggle .icon-sun  { transform: none; opacity: 1; }
.theme-toggle .icon-moon { position: absolute; transform: rotate(-45deg) scale(.5); opacity: 0; }

.menu-toggle {
  display: inline-flex; flex-direction: column; justify-content: center; align-items: center; gap: 5px;
  width: 2.5rem; height: 2.5rem; border-radius: var(--radius-lg); cursor: pointer;
  background: transparent; transition: background var(--t-fast);
}
.menu-toggle:hover { background: var(--color-surface-2); }
.menu-toggle span {
  display: block; width: 1.125rem; height: 2px; background: var(--color-foreground);
  transition: transform var(--t-base), opacity var(--t-fast);
}
.menu-toggle.is-active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.menu-toggle.is-active span:nth-child(2) { opacity: 0; transform: scaleX(0); }
.menu-toggle.is-active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
@media (min-width: 768px) { .menu-toggle { display: none; } }

/* ── Mobile drawer (与顶部导航栏视觉融为一体) ────────────
   关键：drawer 满高自顶部起、去除边框/圆角/阴影，采用与
   navbar 滚动态一致的毛玻璃背景，配合 navbar 更高的 z-index，
   看上去像是导航栏向下延伸而出，无明显边界。 */
.mobile-drawer {
  position: fixed; top: 0; right: 0; width: min(86vw, 22rem);
  height: 100dvh; background: hsla(var(--surface), .94);
  backdrop-filter: blur(16px) saturate(1.4); -webkit-backdrop-filter: blur(16px) saturate(1.4);
  border: none; border-radius: 0; box-shadow: none;
  z-index: var(--z-drawer); padding: calc(var(--nav-h) + var(--space-5)) var(--space-5) var(--space-6);
  display: flex; flex-direction: column; gap: var(--space-1);
  transform: translateX(100%); transition: transform var(--t-slow); overflow-y: auto;
}
.mobile-drawer.is-open { transform: translateX(0); }
.mobile-drawer a {
  display: flex; align-items: center; gap: var(--space-3); padding: .75rem 1rem;
  border-radius: var(--radius-lg); font-size: var(--fz-base); font-weight: 500;
  color: var(--color-foreground); text-decoration: none; transition: background var(--t-fast), color var(--t-fast);
}
.mobile-drawer a svg { width: 1.25rem; height: 1.25rem; color: var(--color-muted); }
.mobile-drawer a:hover { background: var(--color-surface-2); }
.mobile-drawer a.is-active { background: hsla(var(--chino), .12); color: var(--color-chino); font-weight: 600; }
.mobile-drawer a.is-active svg { color: var(--color-chino); }

/* drawer 分隔线（关于 / RSS 之间）：明确可见、居中渐隐两端 */
.drawer-divider {
  flex-shrink: 0; height: 2px; border: none; margin: var(--space-3) .5rem;
  background: linear-gradient(to right,
    transparent, hsla(var(--chino), .45) 15%, var(--color-border-strong) 50%,
    hsla(var(--chino), .45) 85%, transparent);
  border-radius: 1px; opacity: .9;
}

/* drawer 内目录（移动端文章页）：固定在下方空白区，内部滚动 */
.drawer-toc {
  margin-top: auto; padding-top: var(--space-4);
  border-top: 1px solid var(--color-divider-soft);
  max-height: 44vh; overflow-y: auto;
}
.drawer-toc-title { display: flex; align-items: center; gap: .5rem; font-size: var(--fz-xs); font-weight: 700; text-transform: uppercase; letter-spacing: .04em; color: var(--color-muted); margin: 0 0 var(--space-3); }
.drawer-toc-title svg { width: 1rem; height: 1rem; color: var(--color-chino); }

.mobile-backdrop {
  position: fixed; inset: 0; background: hsla(var(--default-900), .4);
  z-index: var(--z-overlay); opacity: 0; visibility: hidden;
  transition: opacity var(--t-base), visibility var(--t-base);
}
.mobile-backdrop.is-open { opacity: 1; visibility: visible; }
@media (min-width: 768px) { .mobile-backdrop { display: none; } .mobile-drawer { display: none; } }

/* ── Back to top (circle, chino glow) ─────────────────────────── */
.back-to-top {
  position: fixed; right: calc(1.25rem + var(--scrollbar-comp, 0px)); bottom: 1.5rem; z-index: var(--z-raised);
  width: 2.75rem; height: 2.75rem; border-radius: var(--radius-full);
  background: hsl(var(--chino)); color: #fff; display: inline-flex; align-items: center; justify-content: center;
  cursor: pointer; box-shadow: var(--shadow-chino); opacity: 0; visibility: hidden;
  transform: translateY(8px) scale(.85);
  transition: opacity var(--t-base), visibility var(--t-base), transform var(--t-spring), background var(--t-fast);
}
.back-to-top svg { width: 1.125rem; height: 1.125rem; }
.back-to-top.is-visible { opacity: 1; visibility: visible; transform: translateY(0) scale(1); }
.back-to-top:hover { background: hsl(var(--chino-600)); transform: translateY(-2px) scale(1.05); }
.back-to-top:active { transform: scale(.95); }
@media (min-width: 640px) { .back-to-top { right: calc(1.75rem + var(--scrollbar-comp, 0px)); bottom: 2rem; width: 3rem; height: 3rem; } .back-to-top svg { width: 1.25rem; height: 1.25rem; } }

/* ── Edit FAB (post page, authed only) — 位于回到顶部按钮上方 ── */
.edit-fab {
  position: fixed; right: calc(1.25rem + var(--scrollbar-comp, 0px)); bottom: 4.75rem; z-index: var(--z-raised);
  width: 2.75rem; height: 2.75rem; border-radius: var(--radius-full);
  background: hsl(var(--accent)); color: #fff; display: inline-flex; align-items: center; justify-content: center;
  cursor: pointer; box-shadow: var(--shadow-chino);
  transition: background var(--t-fast), transform var(--t-spring), box-shadow var(--t-fast);
}
.edit-fab svg { width: 1.125rem; height: 1.125rem; }
.edit-fab:hover { background: hsl(var(--accent-600)); transform: translateY(-2px) scale(1.05); box-shadow: var(--shadow-md); }
.edit-fab:active { transform: scale(.95); }
@media (min-width: 640px) { .edit-fab { right: calc(1.75rem + var(--scrollbar-comp, 0px)); bottom: 5.5rem; width: 3rem; height: 3rem; } .edit-fab svg { width: 1.25rem; height: 1.25rem; } }

/* ── Footer (solid, warm) ────────────────────────────────────── */
.footer {
  width: 100%; margin-top: var(--section-gap);
  border-top: 1px solid var(--color-divider-soft);
  background: var(--color-surface);
}
.footer-inner {
  max-width: var(--content-w); margin-inline: auto; padding: 2rem 1rem;
  display: flex; flex-direction: column; align-items: center; gap: var(--space-6);
}
@media (min-width: 768px) {
  .footer-inner { padding: 2.5rem 2rem; display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; }
}
.footer-brand { display: flex; flex-direction: column; gap: var(--space-2); align-items: center; }
@media (min-width: 768px) { .footer-brand { align-items: flex-start; } }
.footer-logo { display: inline-flex; align-items: center; gap: .5rem; font-weight: 700; font-size: var(--fz-base); color: var(--color-foreground); }
.footer-logo img { width: 1.75rem; height: 1.75rem; border-radius: var(--radius-md); }
.footer-tagline { font-size: var(--fz-xs); color: var(--color-muted); display: inline-flex; align-items: center; gap: .25rem; }
.footer-heart { color: hsl(var(--accent)); display: inline-block; animation: heart-beat 1.5s ease-in-out infinite; }
@keyframes heart-beat { 0%,100% { transform: scale(1); } 30% { transform: scale(1.18); } 60% { transform: scale(.95); } }

.footer-nav { display: flex; flex-wrap: wrap; justify-content: center; gap: var(--space-2) var(--space-5); }
.footer-nav a { display: inline-flex; align-items: center; gap: .3125rem; color: var(--color-muted); font-size: var(--fz-sm); text-decoration: none; transition: color var(--t-fast); }
.footer-nav a:hover { color: var(--color-chino); }
.footer-nav svg { width: 1rem; height: 1rem; }

.footer-social { display: inline-flex; gap: .5rem; }
@media (min-width: 768px) { .footer-social { justify-content: flex-end; } }
.footer-social a {
  display: inline-flex; align-items: center; justify-content: center; width: 2.25rem; height: 2.25rem;
  border-radius: var(--radius-md); color: var(--color-muted); background: var(--color-surface-2);
  transition: background var(--t-fast), color var(--t-fast), transform var(--t-fast);
}
.footer-social a:hover { background: hsla(var(--chino), .12); color: var(--color-chino); transform: translateY(-2px); }