/* ==========================================================================
   xiangyu.io — 极简留白主题
   零第三方依赖：不引用任何 CDN / 网络字体 / 外部脚本
   改配色只需改下面 :root 与 [data-theme="dark"] 里的变量
   ========================================================================== */

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

* {
  margin: 0;
}

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 5.5rem;
}

body {
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

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

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

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

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

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

::selection {
  background: var(--accent-soft);
  color: var(--accent);
}

/* ---------- 设计令牌 ---------- */

:root {
  color-scheme: light;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC",
    "Noto Sans CJK SC", "HarmonyOS Sans SC", "WenQuanYi Micro Hei", sans-serif;
  --font-mono: ui-monospace, "SF Mono", "JetBrains Mono", "Cascadia Code",
    Consolas, "PingFang SC", "Microsoft YaHei", monospace;

  --bg: #fbfbfa;
  --bg-blur: rgba(251, 251, 250, 0.82);
  --surface: #ffffff;
  --surface-2: #f4f4f2;
  --text: #16181a;
  --muted: #5a5f66;
  --faint: #6c7178;
  --border: #e7e6e3;
  --border-strong: #d6d5d1;
  --accent: #2f6b4f;
  --accent-soft: rgba(47, 107, 79, 0.09);

  --max: 45rem;
  --gutter: 1.5rem;
  --gap-section: 7rem;
  --radius: 12px;
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
}

[data-theme="dark"] {
  color-scheme: dark;

  --bg: #0e0f10;
  --bg-blur: rgba(14, 15, 16, 0.82);
  --surface: #15171a;
  --surface-2: #1b1e21;
  --text: #ecedee;
  --muted: #99a0a7;
  --faint: #7b828a;
  --border: #24272a;
  --border-strong: #34383c;
  --accent: #7ec69f;
  --accent-soft: rgba(126, 198, 159, 0.12);

  --gap-section: 6rem;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 1rem;
  transition: background-color 0.35s var(--ease), color 0.35s var(--ease);
}

/* ---------- 布局 ---------- */

.wrap {
  width: 100%;
  max-width: var(--max);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section {
  padding-block: var(--gap-section);
  border-top: 1px solid var(--border);
}

.section-head {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  margin-bottom: 2.75rem;
}

.section-index {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent);
  letter-spacing: 0.06em;
}

.section-title {
  font-size: 1.125rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.section-note {
  margin-left: auto;
  font-size: 0.8125rem;
  color: var(--faint);
}

/* ---------- 页头 ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--bg-blur);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s var(--ease);
}

.site-header.is-stuck {
  border-bottom-color: var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  gap: 1rem;
  height: 3.75rem;
}

.brand {
  font-weight: 600;
  font-size: 0.9375rem;
  letter-spacing: -0.01em;
  white-space: nowrap;
}

.brand span {
  color: var(--faint);
  font-weight: 400;
}

.nav {
  display: flex;
  align-items: center;
  gap: 1.375rem;
  margin-left: auto;
  font-size: 0.875rem;
}

.nav a {
  position: relative;
  color: var(--muted);
  padding-block: 0.25rem;
  transition: color 0.25s var(--ease);
}

.nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 1px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.3s var(--ease);
}

.nav a:hover {
  color: var(--text);
}

.nav a:hover::after,
.nav a.is-active::after {
  transform: scaleX(1);
}

.nav a.is-active {
  color: var(--text);
}

.theme-toggle {
  display: grid;
  place-items: center;
  width: 2rem;
  height: 2rem;
  border-radius: 50%;
  color: var(--muted);
  flex-shrink: 0;
  transition: color 0.25s var(--ease), background-color 0.25s var(--ease);
}

.theme-toggle:hover {
  color: var(--text);
  background: var(--surface-2);
}

.theme-toggle svg {
  width: 17px;
  height: 17px;
}

.theme-toggle .icon-moon {
  display: none;
}

[data-theme="dark"] .theme-toggle .icon-moon {
  display: block;
}

[data-theme="dark"] .theme-toggle .icon-sun {
  display: none;
}

/* ---------- 首屏 ---------- */

.hero {
  padding-block: 6rem 5.5rem;
}

.hero-top {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  margin-bottom: 2.5rem;
}

.avatar {
  width: 5.5rem;
  height: 5.5rem;
  border-radius: 50%;
  object-fit: cover;
  background: var(--surface-2);
  border: 1px solid var(--border);
  flex-shrink: 0;
}

.hero-id h1 {
  font-size: clamp(1.75rem, 5vw, 2.25rem);
  font-weight: 600;
  letter-spacing: -0.025em;
  line-height: 1.2;
}

.hero-role {
  margin-top: 0.375rem;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--muted);
  letter-spacing: 0.02em;
}

.hero-lead {
  font-size: 1.1875rem;
  line-height: 1.85;
  letter-spacing: -0.005em;
  color: var(--text);
  max-width: 34rem;
}

.hero-lead + .hero-lead {
  margin-top: 1.125rem;
  color: var(--muted);
  font-size: 1rem;
}

.hero-lead em {
  font-style: normal;
  color: var(--accent);
  border-bottom: 1px solid var(--accent-soft);
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.5rem;
  margin-top: 2.5rem;
  padding-top: 1.75rem;
  border-top: 1px solid var(--border);
  font-size: 0.8125rem;
  color: var(--muted);
}

.hero-meta li {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

/* ---------- 文章 ---------- */

.posts {
  display: flex;
  flex-direction: column;
}

.post {
  display: grid;
  grid-template-columns: 6.5rem 1fr auto;
  align-items: baseline;
  gap: 1.25rem;
  padding-block: 1.0625rem;
  border-bottom: 1px solid var(--border);
  transition: padding-left 0.3s var(--ease);
}

.post:first-child {
  border-top: 1px solid var(--border);
}

.post:hover {
  padding-left: 0.5rem;
}

.post-date {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--faint);
  letter-spacing: 0.02em;
}

.post-title {
  font-size: 0.9375rem;
  transition: color 0.25s var(--ease);
}

.post:hover .post-title {
  color: var(--accent);
}

.post-meta {
  font-size: 0.75rem;
  color: var(--faint);
  white-space: nowrap;
}

.posts-foot {
  margin-top: 1.5rem;
  font-size: 0.8125rem;
  color: var(--faint);
}

/* ---------- 联系 ---------- */

.contact-mail {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.75rem 1rem;
}

.mail-link {
  font-size: clamp(1.25rem, 4vw, 1.75rem);
  font-weight: 500;
  letter-spacing: -0.02em;
  border-bottom: 1px solid var(--border-strong);
  padding-bottom: 0.125rem;
  transition: color 0.25s var(--ease), border-color 0.25s var(--ease);
}

.mail-link:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

.copy-btn {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.04em;
  color: var(--muted);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.25rem 0.6875rem;
  transition: color 0.25s var(--ease), border-color 0.25s var(--ease),
    background-color 0.25s var(--ease);
}

.copy-btn:hover {
  color: var(--accent);
  border-color: var(--accent);
  background: var(--accent-soft);
}

.copy-btn.is-done {
  color: var(--accent);
  border-color: var(--accent);
}

.contact-desc {
  margin-top: 1.5rem;
  font-size: 0.9375rem;
  color: var(--muted);
  max-width: 32rem;
}

.socials {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 2.25rem;
}

.social {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.8125rem;
  color: var(--muted);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.4375rem 0.9375rem;
  transition: color 0.25s var(--ease), border-color 0.25s var(--ease),
    transform 0.25s var(--ease);
}

.social:hover {
  color: var(--text);
  border-color: var(--border-strong);
  transform: translateY(-1px);
}

.social svg {
  width: 14px;
  height: 14px;
  flex-shrink: 0;
}

/* ---------- 页脚 ---------- */

.site-footer {
  border-top: 1px solid var(--border);
  padding-block: 2.5rem 3.5rem;
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.75rem 1.5rem;
  font-size: 0.8125rem;
  color: var(--faint);
}

.footer-inner a {
  transition: color 0.25s var(--ease);
}

.footer-inner a:hover {
  color: var(--accent);
}

.to-top {
  margin-left: auto;
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
}

.to-top svg {
  width: 12px;
  height: 12px;
}

/* ---------- 滚动揭示（仅在 JS 可用时生效） ---------- */

.js .reveal {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.75s var(--ease), transform 0.75s var(--ease);
  transition-delay: var(--d, 0ms);
}

.js .reveal.is-visible {
  opacity: 1;
  transform: none;
}

/* ---------- 响应式 ---------- */

@media (max-width: 44rem) {
  .hero {
    padding-block: 4rem 3.75rem;
  }

  .hero-top {
    flex-direction: column;
    align-items: flex-start;
    gap: 1.25rem;
  }

  .avatar {
    width: 4.5rem;
    height: 4.5rem;
  }

  .post {
    grid-template-columns: 5.5rem 1fr;
    row-gap: 0.25rem;
  }

  .post-meta {
    grid-column: 2;
  }

  .nav {
    gap: 1rem;
  }

  .section-note {
    display: none;
  }
}

@media (max-width: 26rem) {
  .brand span {
    display: none;
  }

  .nav {
    gap: 0.875rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .js .reveal {
    opacity: 1;
    transform: none;
  }
}