/* ===== 设计变量 ===== */
:root {
  color-scheme: dark;

  --c-text: #f7f4ff;
  --c-text-dim: rgba(247, 244, 255, 0.76);
  --c-accent: #b9a4ff;
  --c-accent-2: #ff9fd2;
  --c-accent-3: #8fe7ff;

  --glass-bg: rgba(255, 255, 255, 0.09);
  --glass-bg-hover: rgba(255, 255, 255, 0.18);
  --glass-border: rgba(255, 255, 255, 0.28);
  --glass-blur: 14px;

  --font-display: 'Zen Maru Gothic', 'Hiragino Maru Gothic ProN', 'Yuanti SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-body: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, Consolas, monospace;

  --radius: 999px;
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);

  --bg-fallback: radial-gradient(120% 120% at 20% 10%, #3b2a68 0%, #1a1430 45%, #0b0a18 100%);
}

/* ===== 基础 ===== */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100svh;
  background: var(--bg-fallback);
  color: var(--c-text);
  font-family: var(--font-body);
  font-size: clamp(15px, 0.6vw + 13px, 17px);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

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

a {
  color: var(--c-accent);
  text-decoration: none;
}

a:hover,
a:focus-visible {
  text-decoration: underline;
  text-underline-offset: 0.2em;
}

:focus-visible {
  outline: 2px solid var(--c-accent-3);
  outline-offset: 3px;
  border-radius: 6px;
}

::selection {
  background: rgba(185, 164, 255, 0.45);
  color: #fff;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ===== 玻璃卡片 ===== */
.glass {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(140%);
  backdrop-filter: blur(var(--glass-blur)) saturate(140%);
  box-shadow:
    0 18px 50px -18px rgba(0, 0, 0, 0.55),
    inset 0 1px 0 rgba(255, 255, 255, 0.22);
}

/* ===== 页面滚动容器 ===== */
.page {
  position: relative;
  z-index: 1;
  min-height: 100svh;
  display: flex;
  flex-direction: column;
}

.container {
  width: min(1080px, 100% - 2.5rem);
  margin-inline: auto;
}

@media (max-width: 640px) {
  .container {
    width: min(1080px, 100% - 1.8rem);
  }
}

/* ===== 顶栏 ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  padding-block: 0.9rem;
  background: linear-gradient(to bottom, rgba(8, 6, 20, 0.55), transparent);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.brand {
  font-family: var(--font-mono);
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--c-text);
  padding: 0.35rem 0.8rem;
  border-radius: var(--radius);
  border: 1px solid transparent;
  transition: border-color 0.25s var(--ease-out), background-color 0.25s var(--ease-out);
}

.brand:hover,
.brand:focus-visible {
  text-decoration: none;
  border-color: var(--glass-border);
  background: var(--glass-bg);
}

.brand__prompt {
  color: var(--c-accent-2);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.site-nav a {
  color: var(--c-text-dim);
  padding: 0.35rem 0.8rem;
  border-radius: var(--radius);
  transition: color 0.2s, background-color 0.2s;
}

.site-nav a:hover,
.site-nav a[aria-current='page'] {
  color: var(--c-text);
  background: var(--glass-bg);
  text-decoration: none;
}

.lang-toggle {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--c-text);
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  padding: 0.35rem 0.85rem;
  cursor: pointer;
  transition: background-color 0.2s, transform 0.2s var(--ease-out);
}

.lang-toggle:hover {
  background: var(--glass-bg-hover);
  transform: translateY(-1px);
}

/* ===== 页脚 ===== */
.site-footer {
  margin-top: auto;
  padding: 2rem 0 1.5rem;
  font-size: 0.82rem;
  color: var(--c-text-dim);
  text-align: center;
}

.site-footer a {
  color: var(--c-text-dim);
}

/* ===== 标签 / 日期 ===== */
.tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 0.1rem 0.55rem;
  border-radius: var(--radius);
  border: 1px solid var(--glass-border);
  color: var(--c-text-dim);
}

.meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem 0.9rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--c-text-dim);
}

/* ===== 动效偏好 ===== */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
}