/* ============================================================
   base.css — reset + 全局排版 + 纸质噪点纹理
   ============================================================ */

/* ---- 现代极简 reset ---- */
*, *::before, *::after { box-sizing: border-box; }

* { margin: 0; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 6rem; /* 锚点跳转避开浮动导航 */
}

body {
  min-height: 100vh;
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: 400;
  line-height: var(--leading-relaxed);
  color: var(--color-fg);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

img, picture, svg, video {
  display: block;
  max-width: 100%;
  height: auto;
}

input, button, textarea, select {
  font: inherit;
  color: inherit;
}

button { cursor: pointer; background: none; border: none; }

a { color: inherit; text-decoration: none; }

ul, ol { list-style: none; padding: 0; }

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: var(--leading-tight);
  color: var(--color-fg);
  letter-spacing: 0.01em;
}

p { line-height: var(--leading-relaxed); }

:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

::selection {
  background: var(--primary-15);
  color: var(--color-fg);
}

/* ---- 纸质噪点纹理叠层（关键：营造侘寂手感） ---- */
body::after {
  content: '';
  position: fixed;
  inset: 0;
  z-index: var(--z-texture);
  pointer-events: none;
  opacity: 0.035;
  mix-blend-mode: multiply;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='300' height='300'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  background-size: 300px 300px;
  background-repeat: repeat;
}

/* ---- 排版基础尺寸（响应式在 layout.css 覆盖） ---- */
.eyebrow {
  display: inline-block;
  font-family: var(--font-body);
  font-weight: 700;
  font-size: var(--text-sm);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-secondary);
  margin-bottom: var(--space-3);
}

.lead {
  font-size: var(--text-lg);
  line-height: var(--leading-relaxed);
  color: var(--color-muted-fg);
}

/* 无障碍：仅屏幕阅读器可见 */
.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;
}

/* 减少动效偏好 */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}