/* ============================================================
   栈间笔记 / Stack Notes
   设计世界：坐标纸 + 工程图纸（graph paper + drafting sheet）
   - 网格纸底、绘图式标题栏、朱红铅笔批注
   - 标题：Smiley Sans（得意黑）  正文：系统中文无衬线
   - 数据与标注：JetBrains Mono
   浅色/深色双主题，默认跟随系统，可手动切换。
   ============================================================ */

/* ---------- 字体 ---------- */

@font-face {
  font-family: "Smiley Sans";
  src: url("../fonts/SmileySans-Oblique.woff2") format("woff2");
  font-weight: 400 800;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: "JetBrains Mono";
  src: url("../fonts/JetBrainsMono-400.woff2") format("woff2");
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: "JetBrains Mono";
  src: url("../fonts/JetBrainsMono-400i.woff2") format("woff2");
  font-weight: 400;
  font-style: italic;
  font-display: swap;
}

@font-face {
  font-family: "JetBrains Mono";
  src: url("../fonts/JetBrainsMono-500.woff2") format("woff2");
  font-weight: 500;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: "JetBrains Mono";
  src: url("../fonts/JetBrainsMono-700.woff2") format("woff2");
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}

/* ---------- 主题 tokens ---------- */

:root {
  --paper: #f6f6f1;
  --paper-2: #eceee9;
  --paper-3: #e3e6e0;
  --ink: #20262e;
  --ink-2: #4c5560;
  --ink-3: #5b6570;
  --line: rgba(38, 50, 66, 0.16);
  --line-strong: rgba(38, 50, 66, 0.34);
  --accent: #b9361f;
  --accent-ink: #8f2412;
  --accent-soft: rgba(185, 54, 31, 0.09);
  --grid: rgba(38, 50, 66, 0.05);
  --grid-major: rgba(38, 50, 66, 0.085);
  --code-bg: #171c23;
  --code-ink: #e8ecf2;
  --focus: #b9361f;
  --shadow: 0 1px 0 rgba(38, 50, 66, 0.06), 0 10px 28px -18px rgba(38, 50, 66, 0.35);
  --radius: 2px;
  --maxw: 1120px;
  --measure: 42rem;
  --font-display: "Smiley Sans", "PingFang SC", "Hiragino Sans GB",
    "Noto Sans SC", "Microsoft YaHei", sans-serif;
  --font-body: "PingFang SC", "Hiragino Sans GB", "Noto Sans SC",
    "Microsoft YaHei", "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SF Mono", "Cascadia Mono",
    Consolas, "Liberation Mono", monospace;
}

[data-theme="dark"] {
  --paper: #10141a;
  --paper-2: #171d25;
  --paper-3: #20262f;
  --ink: #e6eaf0;
  --ink-2: #9aa5b1;
  --ink-3: #75808c;
  --line: rgba(214, 226, 240, 0.16);
  --line-strong: rgba(214, 226, 240, 0.34);
  --accent: #ff7b55;
  --accent-ink: #ff9271;
  --accent-soft: rgba(255, 123, 85, 0.12);
  --grid: rgba(214, 226, 240, 0.045);
  --grid-major: rgba(214, 226, 240, 0.08);
  --code-bg: #0c1015;
  --code-ink: #dde4ec;
  --focus: #ff7b55;
  --shadow: 0 1px 0 rgba(0, 0, 0, 0.35), 0 12px 30px -18px rgba(0, 0, 0, 0.7);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #10141a;
    --paper-2: #171d25;
    --paper-3: #20262f;
    --ink: #e6eaf0;
    --ink-2: #9aa5b1;
    --ink-3: #75808c;
    --line: rgba(214, 226, 240, 0.16);
    --line-strong: rgba(214, 226, 240, 0.34);
    --accent: #ff7b55;
    --accent-ink: #ff9271;
    --accent-soft: rgba(255, 123, 85, 0.12);
    --grid: rgba(214, 226, 240, 0.045);
    --grid-major: rgba(214, 226, 240, 0.08);
    --code-bg: #0c1015;
    --code-ink: #dde4ec;
    --focus: #ff7b55;
    --shadow: 0 1px 0 rgba(0, 0, 0, 0.35), 0 12px 30px -18px rgba(0, 0, 0, 0.7);
  }
}

/* ---------- 基础 ---------- */

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

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

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

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

/* 网格纸底：固定图层，不参与滚动性能开销 */
/* impeccable-disable-next-line codex-grid-background -- 坐标纸即本站的纸张材质，属已承诺的绘图世界，非装饰网格 */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px),
    linear-gradient(var(--grid-major) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-major) 1px, transparent 1px);
  background-size:
    8px 8px,
    8px 8px,
    40px 40px,
    40px 40px;
}

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

a {
  color: inherit;
  text-decoration-color: var(--line-strong);
  text-underline-offset: 3px;
}

a:hover {
  color: var(--accent-ink);
}

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

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

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--ink);
  color: var(--paper);
  padding: 0.6rem 1rem;
  z-index: 100;
}

.skip-link:focus {
  left: 0;
}

.container {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.mono {
  font-family: var(--font-mono);
  font-size: 0.78em;
  letter-spacing: 0.04em;
}

.accent {
  color: var(--accent-ink);
}

/* ---------- 排版 ---------- */

h1,
h2,
h3,
h4 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.16;
  letter-spacing: -0.01em;
  margin: 0 0 0.5em;
  text-wrap: balance;
}

h1 {
  font-size: clamp(2.1rem, 5.6vw, 3.7rem);
  letter-spacing: -0.02em;
}

h2 {
  font-size: clamp(1.45rem, 3vw, 1.9rem);
  letter-spacing: -0.015em;
}

h3 {
  font-size: 1.25rem;
}

p {
  margin: 0 0 1.25em;
}

.lede {
  font-size: 1.12rem;
  color: var(--ink-2);
  max-width: 46ch;
}

/* ---------- 按钮 ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.72rem 1.35rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  background: transparent;
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 0.98rem;
  font-weight: 600;
  line-height: 1.2;
  text-decoration: none;
  cursor: pointer;
  transition: background-color 0.18s ease-out, border-color 0.18s ease-out,
    color 0.18s ease-out, transform 0.08s ease-out;
}

.btn:hover {
  color: var(--accent-ink);
  border-color: var(--accent);
}

.btn:active {
  transform: translateY(1px);
}

.btn-primary {
  background: var(--ink);
  border-color: var(--ink);
  color: var(--paper);
}

.btn-primary:hover {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

.btn svg {
  width: 1em;
  height: 1em;
  flex: none;
}

/* ---------- 页头 ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  height: 64px;
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}

@media (prefers-reduced-transparency: reduce) {
  .site-header {
    background: var(--paper);
    -webkit-backdrop-filter: none;
    backdrop-filter: none;
  }
}

.site-header .container {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.brand {
  display: inline-flex;
  align-items: baseline;
  gap: 0.65rem;
  font-family: var(--font-display);
  font-size: 1.3rem;
  font-weight: 800;
  text-decoration: none;
  white-space: nowrap;
}

.brand small {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  font-weight: 400;
  letter-spacing: 0.14em;
  color: var(--ink-3);
  text-transform: uppercase;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.main-nav a {
  padding: 0.45rem 0.85rem;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--ink-2);
  text-decoration: none;
  border-radius: var(--radius);
  white-space: nowrap;
}

.main-nav a:hover {
  color: var(--accent-ink);
  background: var(--accent-soft);
}

.main-nav a[aria-current="page"] {
  color: var(--ink);
  box-shadow: inset 0 -2px 0 var(--accent);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: transparent;
  color: var(--ink-2);
  cursor: pointer;
  transition: color 0.18s ease-out, border-color 0.18s ease-out,
    background-color 0.18s ease-out;
}

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

.icon-btn:active {
  transform: translateY(1px);
}

.icon-btn svg {
  width: 17px;
  height: 17px;
}

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

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

.nav-toggle {
  display: none;
}

/* ---------- 页脚 ---------- */

.site-footer {
  border-top: 1px solid var(--line);
  margin-top: 5rem;
  padding: 3rem 0 2.5rem;
  color: var(--ink-2);
  font-size: 0.9rem;
}

.site-footer .container {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 2.5rem;
}

.site-footer h3 {
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--ink);
  margin-bottom: 0.8rem;
}

.site-footer ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.45rem;
}

.site-footer a {
  text-decoration: none;
  color: var(--ink-2);
}

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

.footer-meta {
  grid-column: 1 / -1;
  border-top: 1px solid var(--line);
  padding-top: 1.5rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem 1.8rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.02em;
}

.footer-meta a {
  text-decoration: none;
}

.beian a {
  color: var(--ink-3);
}

.beian a:hover {
  color: var(--accent-ink);
}

/* ---------- 绘图框（hero / 通用大板） ---------- */

.sheet {
  position: relative;
  border: 1px solid var(--line-strong);
  background:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px),
    linear-gradient(var(--grid-major) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-major) 1px, transparent 1px),
    var(--paper);
  background-size:
    8px 8px,
    8px 8px,
    40px 40px,
    40px 40px;
  box-shadow: var(--shadow);
}

.sheet::after {
  content: "";
  position: absolute;
  inset: 6px;
  border: 1px solid var(--line);
  pointer-events: none;
}

.sheet-head {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.1rem 1.4rem 0.9rem;
  border-bottom: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--ink-3);
  text-transform: uppercase;
}

.title-block {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  border-top: 1px solid var(--line-strong);
  font-family: var(--font-mono);
  font-size: 0.72rem;
}

.title-block div {
  padding: 0.55rem 0.8rem;
  border-right: 1px solid var(--line);
  min-width: 0;
}

.title-block div:last-child {
  border-right: 0;
}

.title-block b {
  display: block;
  font-weight: 500;
  color: var(--ink-3);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 0.15rem;
}

.title-block span {
  display: block;
  color: var(--ink);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* ---------- Hero ---------- */

.hero {
  padding: 2.5rem 0 0;
}

.hero .sheet-head {
  align-items: baseline;
}

.hero-body {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 3rem;
  align-items: center;
  padding: 3.2rem 3rem 3.5rem;
}

.hero h1 {
  margin-bottom: 0.5em;
}

.hero .lede {
  margin-bottom: 1.9rem;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
}

.hero-figure {
  border: 1px solid var(--line);
  background: color-mix(in srgb, var(--paper-2) 72%, transparent);
  padding: 0.9rem;
}

.hero-figure svg {
  width: 100%;
  height: auto;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 2rem;
  padding: 0.8rem 1.4rem;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--ink-3);
}

.hero-meta em {
  font-style: normal;
  color: var(--accent-ink);
}

/* ---------- 区块通用 ---------- */

.section {
  padding: 4.5rem 0 0;
}

.section-head {
  margin-bottom: 2rem;
}

.section-head h2 {
  margin-bottom: 0.35rem;
}

.section-head p {
  margin: 0;
  color: var(--ink-2);
  max-width: 60ch;
}

.section-foot {
  margin-top: 1.8rem;
}

/* ---------- 文章登记表（register） ---------- */

.register {
  border-top: 2px solid var(--ink);
}

.register-row {
  display: grid;
  grid-template-columns: 8rem 1fr auto;
  gap: 1.5rem;
  align-items: baseline;
  padding: 1.15rem 0.4rem;
  border-bottom: 1px solid var(--line);
  text-decoration: none;
  transition: background-color 0.18s ease-out;
}

.register-row:hover {
  background: var(--accent-soft);
}

.register-no {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent-ink);
  letter-spacing: 0.05em;
}

.register-main h3 {
  font-family: var(--font-display);
  font-size: 1.22rem;
  margin-bottom: 0.25rem;
}

.register-main p {
  margin: 0;
  color: var(--ink-2);
  font-size: 0.95rem;
  max-width: 58ch;
}

.register-meta {
  text-align: right;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--ink-3);
  line-height: 1.9;
  white-space: nowrap;
}

.register-meta .tag {
  color: var(--ink-2);
}

/* ---------- 主题图例 ---------- */

.legend {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  border-top: 2px solid var(--ink);
}

.legend-item {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.95rem 0.4rem;
  border-bottom: 1px solid var(--line);
  text-decoration: none;
  transition: background-color 0.18s ease-out;
}

.legend-item:nth-child(odd) {
  border-right: 1px solid var(--line);
  padding-right: 1.4rem;
}

.legend-item:nth-child(even) {
  padding-left: 1.4rem;
}

.legend-item:hover {
  background: var(--accent-soft);
}

.legend-name {
  font-family: var(--font-display);
  font-size: 1.12rem;
  font-weight: 700;
}

.legend-count {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--ink-3);
}

/* ---------- 关于摘要 ---------- */

.about-strip {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 2.5rem;
  align-items: center;
  padding: 2rem 2.4rem;
}

.about-strip p {
  margin: 0 0 1rem;
  color: var(--ink-2);
  max-width: 62ch;
}

/* ---------- 文章页 ---------- */

.post-header {
  padding-top: 2.4rem;
}

.post-kicker {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.6rem;
  margin-bottom: 1.1rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--ink-3);
}

.post-kicker .drg {
  color: var(--accent-ink);
}

.post-header h1 {
  max-width: 22ch;
  margin-bottom: 0.45em;
}

.post-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.8rem;
  padding: 0.85rem 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--ink-2);
}

.post-cover {
  margin: 2.2rem 0;
  border: 1px solid var(--line);
  background: color-mix(in srgb, var(--paper-2) 72%, transparent);
  padding: 1rem;
}

.post-cover svg {
  width: 100%;
  height: auto;
}

.post-layout {
  display: grid;
  grid-template-columns: 14rem minmax(0, 1fr);
  gap: 3rem;
  align-items: start;
}

.post-layout > * {
  min-width: 0;
}

.post-toc {
  position: sticky;
  top: 88px;
  font-size: 0.88rem;
  border-left: 2px solid var(--ink);
  padding-left: 1rem;
}

.post-toc h2 {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  color: var(--ink-3);
  text-transform: uppercase;
  margin-bottom: 0.8rem;
}

.post-toc ol {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.45rem;
}

.post-toc a {
  color: var(--ink-2);
  text-decoration: none;
}

.post-toc a:hover {
  color: var(--accent-ink);
}

.post-toc a[data-active="true"] {
  color: var(--accent-ink);
}

.post-body {
  max-width: var(--measure);
  font-size: 1.04rem;
}

.post-body h2 {
  margin-top: 2.6em;
  padding-top: 0.3em;
  border-top: 1px dashed var(--line-strong);
  position: relative;
}

.post-body h2::before {
  content: attr(data-no);
  position: absolute;
  right: 100%;
  margin-right: 0.8rem;
  top: 0.9em;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 400;
  color: var(--accent-ink);
  letter-spacing: 0.06em;
}

.post-body h3 {
  margin-top: 2em;
}

.post-body ul,
.post-body ol {
  padding-left: 1.3em;
}

.post-body li {
  margin-bottom: 0.45em;
}

.post-body code {
  font-family: var(--font-mono);
  font-size: 0.86em;
  background: var(--paper-3);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0.12em 0.38em;
}

.post-body pre {
  background: var(--code-bg);
  color: var(--code-ink);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  padding: 1.1rem 1.25rem;
  overflow-x: auto;
  font-size: 0.9rem;
  line-height: 1.7;
  margin: 1.6em 0;
}

.post-body pre code {
  background: none;
  border: 0;
  padding: 0;
  color: inherit;
  font-size: inherit;
}

.post-body blockquote {
  margin: 1.8em 0;
  padding: 1.15em 1.2em 0.9em;
  border: 1px solid var(--accent);
  color: var(--ink-2);
  font-style: normal;
  position: relative;
}

.post-body blockquote::before {
  content: "批注";
  position: absolute;
  left: 0.9rem;
  top: -0.72em;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  color: var(--accent-ink);
  text-transform: uppercase;
  background: var(--paper);
  padding: 0 0.35em;
}

.post-body blockquote p:last-child {
  margin-bottom: 0;
}

.post-body table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
  margin: 1.6em 0;
  display: block;
  overflow-x: auto;
}

.post-body th,
.post-body td {
  text-align: left;
  padding: 0.6rem 0.8rem;
  border-bottom: 1px solid var(--line);
}

.post-body th {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  color: var(--ink-3);
  text-transform: uppercase;
  border-bottom: 2px solid var(--ink);
}

.post-body hr {
  border: 0;
  border-top: 1px dashed var(--line-strong);
  margin: 2.5em 0;
}

.post-body .fig {
  margin: 1.8em 0;
  border: 1px solid var(--line);
  padding: 0.9rem;
  background: color-mix(in srgb, var(--paper-2) 70%, transparent);
}

.post-body .fig figcaption {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--ink-3);
  margin-top: 0.7rem;
}

.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 100%;
  background: var(--accent);
  z-index: 60;
  pointer-events: none;
  transform: scaleX(0);
  transform-origin: 0 0;
}

@supports (animation-timeline: scroll()) {
  .reading-progress {
    animation: progress-grow linear both;
    animation-timeline: scroll(root);
  }
}

@keyframes progress-grow {
  from {
    transform: scaleX(0);
  }
  to {
    transform: scaleX(1);
  }
}

.post-footer-nav {
  margin-top: 3.5rem;
  border-top: 2px solid var(--ink);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
}

.post-footer-nav a {
  display: block;
  padding: 1.2rem 0.4rem;
  text-decoration: none;
}

.post-footer-nav a + a {
  text-align: right;
}

.post-footer-nav small {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--ink-3);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 0.35rem;
}

.post-footer-nav span {
  font-family: var(--font-display);
  font-size: 1.08rem;
  font-weight: 700;
}

.post-footer-nav a:hover span {
  color: var(--accent-ink);
}

/* ---------- 归档页 ---------- */

.archive-toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  align-items: end;
  padding: 1.2rem 0;
  border-top: 2px solid var(--ink);
  border-bottom: 1px solid var(--line);
  margin-bottom: 1.6rem;
}

.field {
  display: grid;
  gap: 0.35rem;
  flex: 1 1 220px;
  max-width: 340px;
}

.field label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-3);
}

.field input,
.field select {
  width: 100%;
  padding: 0.6rem 0.75rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 0.95rem;
}

.field input::placeholder {
  color: var(--ink-3);
}

.field input:focus,
.field select:focus {
  outline: 2px solid var(--focus);
  outline-offset: 1px;
  border-color: var(--accent);
}

.archive-empty {
  display: none;
  padding: 3rem 0.4rem;
  color: var(--ink-2);
  border-bottom: 1px solid var(--line);
}

.archive-empty[data-visible="true"] {
  display: block;
}

.year-group {
  margin-bottom: 2.2rem;
}

.year-label {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  color: var(--ink-3);
  text-transform: uppercase;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--line);
  margin-bottom: 0.5rem;
}

/* ---------- 关于页 ---------- */

.about-grid {
  display: grid;
  grid-template-columns: 17rem minmax(0, 1fr);
  gap: 3rem;
  align-items: start;
}

.portrait {
  border: 1px dashed var(--line-strong);
  aspect-ratio: 4 / 5;
  display: grid;
  place-items: center;
  text-align: center;
  color: var(--ink-3);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.1em;
  background:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px),
    var(--paper-2);
  background-size: 16px 16px, 16px 16px;
  padding: 1rem;
}

.portrait span {
  display: block;
  max-width: 16ch;
  line-height: 1.7;
}

.about-body {
  max-width: var(--measure);
}

.about-body h2 {
  margin-top: 2em;
}

.contact-list {
  list-style: none;
  margin: 1.4em 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.contact-list li {
  display: flex;
  gap: 1rem;
  justify-content: space-between;
  padding: 0.75rem 0.2rem;
  border-bottom: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 0.86rem;
}

.contact-list .k {
  color: var(--ink-3);
}

/* ---------- 404 ---------- */

.notfound {
  padding: 5rem 0;
  text-align: left;
}

.notfound .code {
  font-family: var(--font-mono);
  font-size: clamp(4rem, 12vw, 7rem);
  line-height: 1;
  color: var(--accent-ink);
  letter-spacing: -0.04em;
  margin-bottom: 0.6rem;
}

/* ---------- 动效 ---------- */

.reveal {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.55s cubic-bezier(0.16, 1, 0.3, 1),
    transform 0.55s cubic-bezier(0.16, 1, 0.3, 1);
}

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

@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0.001s !important;
    transition-duration: 0.001s !important;
  }
}

/* ---------- 响应式 ---------- */

@media (max-width: 960px) {
  .hero-body {
    grid-template-columns: 1fr;
    padding: 2.4rem 2rem;
  }
  .hero-figure {
    order: -1;
  }
  .post-layout {
    grid-template-columns: 1fr;
  }
  .post-toc {
    display: none;
  }
  .about-grid {
    grid-template-columns: 1fr;
  }
  .portrait {
    max-width: 17rem;
  }
}

@media (max-width: 760px) {
  body {
    font-size: 16px;
  }
  .title-block {
    grid-template-columns: repeat(3, 1fr);
  }
  .title-block div {
    border-bottom: 1px solid var(--line);
  }
  .title-block div:nth-child(3n) {
    border-right: 0;
  }
  .title-block div:nth-last-child(-n + 3) {
    border-bottom: 0;
  }
  .register-row {
    grid-template-columns: 5.5rem 1fr;
    gap: 0.8rem;
  }
  .register-meta {
    grid-column: 2;
    text-align: left;
  }
  .legend {
    grid-template-columns: 1fr;
  }
  .legend-item:nth-child(odd) {
    border-right: 0;
    padding-right: 0.4rem;
  }
  .legend-item:nth-child(even) {
    padding-left: 0.4rem;
  }
  .about-strip {
    grid-template-columns: 1fr;
    padding: 1.6rem 1.4rem;
  }
  .site-footer .container {
    grid-template-columns: 1fr;
    gap: 1.8rem;
  }
  .post-footer-nav {
    grid-template-columns: 1fr;
    gap: 0;
  }
  .post-footer-nav a + a {
    text-align: left;
  }
  .main-nav {
    position: fixed;
    inset: 64px 0 auto 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: var(--paper);
    border-bottom: 1px solid var(--line);
    padding: 0.6rem 1rem 1rem;
    transform: translateY(-110%);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transition: transform 0.24s cubic-bezier(0.16, 1, 0.3, 1),
      opacity 0.24s ease-out, visibility 0s linear 0.24s;
    box-shadow: var(--shadow);
  }
  .main-nav[data-open="true"] {
    transform: none;
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transition: transform 0.24s cubic-bezier(0.16, 1, 0.3, 1),
      opacity 0.24s ease-out;
  }
  .main-nav a {
    padding: 0.8rem 0.85rem;
  }
  .nav-toggle {
    display: inline-flex;
  }
}

@media print {
  body::before,
  .site-header,
  .site-footer,
  .post-toc,
  .reading-progress,
  .hero-figure {
    display: none !important;
  }
  body {
    background: #fff;
    color: #000;
  }
  .container {
    max-width: 100%;
  }
  .sheet {
    border: 1px solid #000;
    box-shadow: none;
  }
}