@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+Hebrew:wght@300;400;500;700&display=swap');

:root {
  --ink: #000000;
  --paper: #ffffff;
  --mute: #565656;
  --soft: #f4f4f4;
  --glass: rgba(255, 255, 255, 0.62);
  --rail: 236px;
}

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

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

body {
  margin: 0;
  overflow-x: hidden;
  background: var(--paper);
  color: var(--ink);
  font-family: 'Noto Sans Hebrew', system-ui, -apple-system, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  font-size: 17px;
  line-height: 1.7;
  font-weight: 400;
}

p {
  font-size: 17px;
  line-height: 1.75;
}

img {
  max-width: 100%;
}

/* ---------- 顶部细条 ---------- */
.topbar {
  position: fixed;
  z-index: 40;
  inset: 0 0 auto 0;
  height: 32px;
  display: flex;
  align-items: center;
  background: var(--ink);
  color: var(--paper);
}

.topbar p {
  margin: 0 0 0 74px;
  font-size: 12.5px;
  line-height: 1;
  letter-spacing: 0.34em;
  font-weight: 500;
}

/* ---------- 角落图标 ---------- */
.mark {
  position: fixed;
  z-index: 50;
  top: 46px;
  left: 24px;
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  border: 1px solid var(--ink);
  background: var(--paper);
  text-decoration: none;
  transition: background 0.22s ease;
}

.mark img {
  display: block;
  width: 26px;
  height: 26px;
  object-fit: contain;
}

.mark-box {
  width: 12px;
  height: 12px;
  background: var(--ink);
  transition: transform 0.22s ease;
}

.mark:hover .mark-box {
  transform: rotate(45deg);
}

.mark:hover {
  background: #ececec;
}

/* ---------- 左侧竖排导航 ---------- */
.rail {
  position: fixed;
  z-index: 30;
  top: 0;
  left: 0;
  bottom: 0;
  width: var(--rail);
  padding-top: 112px;
  border-right: 1px solid var(--ink);
  background: var(--paper);
}

.rail nav {
  width: 100%;
}

.rail-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.rail-list li {
  border-bottom: 1px solid #e2e2e2;
}

.rail-list li:first-child {
  border-top: 1px solid #e2e2e2;
}

.rail-list a {
  display: flex;
  align-items: center;
  min-height: 46px;
  padding: 8px 22px;
  color: var(--ink);
  font-size: 15px;
  line-height: 1.35;
  letter-spacing: 0.02em;
  text-decoration: none;
  transition: background 0.22s ease, color 0.22s ease, padding-left 0.22s ease;
}

.rail-list a:hover,
.rail-list a:focus-visible {
  background: var(--ink);
  color: var(--paper);
  padding-left: 28px;
}

/* ---------- 主体骨架 ---------- */
main {
  margin-left: var(--rail);
  padding: 0 clamp(20px, 4vw, 56px) 0 clamp(20px, 4vw, 56px);
  display: grid;
  grid-template-columns: minmax(0, 1fr) 250px;
  gap: 0 56px;
  max-width: 1320px;
}

/* ---------- 首屏 ---------- */
.hero {
  grid-column: 1 / -1;
  position: relative;
  overflow: hidden;
  min-height: 100vh;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 0.55fr);
  align-items: center;
  gap: 48px;
  padding: 128px 0 120px;
}

.hero::after {
  content: '';
  position: absolute;
  left: -8%;
  right: -8%;
  bottom: 52px;
  height: 78px;
  background: var(--ink);
  transform: rotate(-5deg);
  transform-origin: left center;
}

.hero-copy {
  position: relative;
  z-index: 2;
}

h1 {
  margin: 0 0 24px;
  font-size: clamp(40px, 6.4vw, 82px);
  line-height: 1;
  font-weight: 700;
  letter-spacing: -0.045em;
  max-width: 16ch;
}

.hero-lead {
  margin: 0;
  max-width: 34ch;
  font-size: 17px;
  line-height: 1.75;
  color: #111111;
}

.hero-fig {
  position: relative;
  z-index: 2;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  padding: 10px;
  border: 1px solid var(--ink);
  background: var(--glass);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.hero-fig span {
  display: block;
  aspect-ratio: 1 / 1;
  border: 1px solid var(--ink);
}

.fig-a {
  background: var(--ink);
}

.fig-b {
  background: repeating-linear-gradient(45deg, #000 0 2px, #fff 2px 9px);
}

.fig-c {
  grid-column: span 2;
  aspect-ratio: 2 / 1;
  background: var(--paper);
}

.hero-img {
  grid-column: span 2;
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  border: 1px solid var(--ink);
}

/* ---------- 正文 ---------- */
.content {
  grid-column: 1;
  min-width: 0;
  padding-bottom: 40px;
}

.content > section {
  padding: clamp(46px, 6vw, 84px) 0;
  border-top: 1px solid var(--ink);
  scroll-margin-top: 84px;
}

.content > section:first-child {
  border-top: 0;
  padding-top: 0;
}

.content > section:nth-child(even) {
  padding-left: clamp(0px, 3vw, 44px);
}

.content h2 {
  margin: 0 0 10px;
  font-size: clamp(24px, 3.2vw, 34px);
  line-height: 1.2;
  font-weight: 700;
  letter-spacing: -0.025em;
}

.content h3 {
  margin: 30px 0 10px;
  font-size: 20px;
  line-height: 1.35;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.content p {
  max-width: 66ch;
  margin: 0 0 18px;
}

.content ul,
.content ol {
  max-width: 66ch;
  margin: 0 0 20px;
  padding-left: 1.25em;
}

.content li {
  margin-bottom: 8px;
}

p.subtitle {
  margin: 0 0 26px;
  font-size: 15px;
  line-height: 1.6;
  letter-spacing: 0.1em;
  color: var(--mute);
}

.content a {
  color: var(--ink);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
  transition: background 0.2s ease;
}

.content a:hover {
  background: #ededed;
}

.content blockquote {
  margin: 0 0 22px;
  padding: 16px 22px;
  border-left: 4px solid var(--ink);
  background: var(--soft);
  max-width: 66ch;
}

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

.content figure {
  margin: 0 0 22px;
}

.content img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--ink);
}

.content figcaption {
  margin-top: 8px;
  font-size: 14px;
  color: var(--mute);
  letter-spacing: 0.02em;
}

.content table {
  width: 100%;
  border-collapse: collapse;
  margin: 0 0 22px;
  font-size: 16px;
}

.content th,
.content td {
  border: 1px solid var(--ink);
  padding: 10px 12px;
  text-align: left;
}

.content code {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 15px;
  background: var(--soft);
  padding: 1px 4px;
}

/* ---------- 右侧栏 ---------- */
.side {
  grid-column: 2;
  align-self: start;
  position: sticky;
  top: 96px;
  padding-bottom: 60px;
}

.side h2 {
  margin: 0 0 6px;
  font-size: 15px;
  line-height: 1.4;
  font-weight: 700;
  letter-spacing: 0.28em;
}

.side p.subtitle {
  margin: 0 0 16px;
  font-size: 14px;
  letter-spacing: 0.08em;
}

.side-box {
  border: 1px solid var(--ink);
  background: var(--glass);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  padding: 6px 16px;
}

.side-box ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.side-box li:last-child a {
  border-bottom: 0;
}

.side-box a {
  display: block;
  min-height: 40px;
  padding: 9px 0;
  border-bottom: 1px solid #dedede;
  color: var(--ink);
  font-size: 15px;
  line-height: 1.4;
  text-decoration: none;
  transition: padding-left 0.22s ease, opacity 0.22s ease;
}

.side-box a:hover,
.side-box a:focus-visible {
  padding-left: 7px;
  opacity: 0.62;
}

/* ---------- 页脚 ---------- */
footer {
  margin-left: var(--rail);
  margin-top: 40px;
  padding: 40px clamp(20px, 4vw, 56px) 56px;
  border-top: 1px solid var(--ink);
  display: grid;
  grid-template-columns: 1fr 1.6fr 1fr;
  gap: 18px 32px;
  align-items: start;
}

footer p {
  margin: 0;
  font-size: 15px;
  line-height: 1.6;
}

.f-brand {
  font-weight: 700;
  letter-spacing: 0.16em;
}

.f-desc {
  color: var(--mute);
  text-align: center;
}

.f-copy {
  display: block;
  font-size: 14px;
  line-height: 1.6;
  text-align: center;
  color: var(--mute);
}

/* ---------- 滚动显现 ---------- */
.js .reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

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

/* ---------- 响应式 ---------- */
@media (max-width: 1080px) {
  main {
    grid-template-columns: minmax(0, 1fr) 210px;
    gap: 0 34px;
  }
}

@media (max-width: 860px) {
  .topbar {
    display: none;
  }

  .mark {
    top: 6px;
    left: 10px;
    width: 32px;
    height: 32px;
    z-index: 60;
  }

  .rail {
    position: sticky;
    top: 0;
    left: auto;
    bottom: auto;
    width: auto;
    padding: 0;
    border-right: 0;
    border-bottom: 1px solid var(--ink);
    background: rgba(255, 255, 255, 0.94);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
  }

  .rail nav {
    overflow-x: auto;
    overscroll-behavior-x: contain;
    scrollbar-width: none;
  }

  .rail nav::-webkit-scrollbar {
    display: none;
  }

  .rail-list {
    display: flex;
    align-items: stretch;
    padding-left: 52px;
  }

  .rail-list li,
  .rail-list li:first-child {
    border: 0;
    border-right: 1px solid #e6e6e6;
    flex: 0 0 auto;
  }

  .rail-list a {
    min-height: 44px;
    padding: 0 14px;
    font-size: 15px;
    white-space: nowrap;
  }

  .rail-list a:hover {
    padding-left: 14px;
  }

  main {
    margin-left: 0;
    padding: 0 18px;
    grid-template-columns: minmax(0, 1fr);
    gap: 0;
  }

  .hero {
    min-height: 0;
    grid-template-columns: minmax(0, 1fr);
    gap: 28px;
    padding: 46px 0 78px;
  }

  .hero::after {
    bottom: 20px;
    height: 36px;
  }

  h1 {
    font-size: clamp(34px, 10vw, 46px);
    max-width: 14ch;
  }

  .hero-fig {
    max-width: 320px;
  }

  .content > section,
  .content > section:nth-child(even) {
    padding-left: 0;
    scroll-margin-top: 68px;
    padding-top: 38px;
    padding-bottom: 38px;
  }

  .side {
    grid-column: 1;
    position: static;
    padding: 34px 0 10px;
    border-top: 1px solid var(--ink);
  }

  .side-box a {
    min-height: 44px;
    padding: 11px 0;
  }

  footer {
    margin-left: 0;
    padding: 32px 18px 44px;
    grid-template-columns: minmax(0, 1fr);
    text-align: center;
    gap: 10px;
  }

  .f-brand,
  .f-desc,
  .f-copy {
    text-align: center;
  }
}

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

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

button[aria-expanded]{min-width:44px;min-height:44px}