/* ============================================================
   FDE事务所 — 基础样式 / Base
   reset + 排版 + 工具类
   ============================================================ */

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

html {
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--fde-font-sans);
  font-size: var(--fs-body);
  line-height: var(--lh-normal);
  color: var(--fde-white);
  background: var(--fde-obsidian-950);
  -webkit-tap-highlight-color: transparent;
  overflow-x: hidden;
}

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

a {
  color: inherit;
  text-decoration: none;
  transition: opacity var(--dur-fast) var(--ease-out);
}
a:hover { opacity: 0.78; }
a:focus-visible { outline: none; box-shadow: var(--fde-focus); }

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
}

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

h1, h2, h3, h4, h5, h6, p, figure, blockquote {
  margin: 0;
}

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

hr {
  border: 0;
  height: var(--hairline);
  background: var(--fde-line-dark);
  margin: 0;
}

::selection {
  background: var(--fde-white);
  color: var(--fde-obsidian-950);
}

/* 暖白阅读区 */
.surface-paper {
  background: var(--fde-paper);
  color: var(--fde-graphite);
}
.surface-paper p { color: #2A2A2B; }
.surface-paper .eyebrow { color: #6E6F70; }
.surface-paper .eyebrow::before { background: var(--fde-line-light-strong); }

/* 排版 */
.eyebrow {
  font-family: var(--fde-font-mono);
  font-size: var(--fs-eyebrow);
  line-height: 1.5;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--fde-titanium);
  font-weight: var(--fw-medium);
  display: inline-flex;
  align-items: center;
  gap: 12px;
}
.eyebrow::before {
  content: "";
  display: inline-block;
  width: 32px;
  height: var(--hairline);
  background: var(--fde-line-dark);
}

.lead {
  max-width: 720px;
  color: var(--fde-silver-light);
  font-size: clamp(17px, 1.4vw, 20px);
  line-height: 1.8;
}
.surface-paper .lead { color: #2A2A2B; }

p {
  font-size: var(--fs-body);
  line-height: var(--lh-loose);
  color: var(--fde-titanium);
}
.surface-paper p { color: #2A2A2B; }

.mono {
  font-family: var(--fde-font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.04em;
  color: var(--fde-muted);
}
.surface-paper .mono { color: #6E6F70; }

/* 正式浅色区块上下文 */
.fde-section--paper p,
.fde-section--paper .lead { color: #2A2A2B; }
.fde-section--paper .eyebrow,
.fde-section--paper .mono { color: #5F6062; }
.fde-section--paper .eyebrow::before { background: var(--fde-line-light-strong); }

/* 容器 */
.fde-container {
  width: min(calc(100% - (2 * var(--fde-gutter))), var(--fde-content-max));
  margin-inline: auto;
}

/* 节奏 */
.section { padding-block: var(--fde-section-space); position: relative; }
.section-sm { padding-block: clamp(64px, 8vw, 120px); }

/* 状态徽章 */
.fde-status {
  min-height: 28px;
  padding-inline: 10px;
  display: inline-flex;
  align-items: center;
  border: 1px solid currentColor;
  border-radius: var(--radius-1);
  color: inherit;
  font: 500 11px/1 var(--fde-font-mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  white-space: nowrap;
}

/* 发丝线 */
.fde-hairline {
  height: var(--hairline);
  border: 0;
  background: currentColor;
  opacity: 0.2;
}

/* 链接 */
.fde-link {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid currentColor;
  transition: opacity var(--dur-fast) var(--ease-out);
}
.fde-link:hover { opacity: 0.62; }

/* 视觉隐藏 */
.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;
}

/* 跳过链接 */
.skip-link {
  position: absolute;
  top: -64px;
  left: 16px;
  background: var(--fde-white);
  color: var(--fde-obsidian-950);
  padding: 12px 20px;
  font-size: 14px;
  z-index: 100;
}
.skip-link:focus { top: 16px; }

@media (max-width: 640px) {
  :root {
    --fs-body: 16px;
    --fs-body-lg: 17px;
  }
}