@import url('https://fonts.googleapis.com/css2?family=Fira+Code:wght@300;400;500;600;700&family=Share+Tech+Mono&display=swap');

/* ========== 基础变量 ========== */
:root {
  --cream: #f5e6c8;
  --caramel: #d4a574;
  --dark: #262117;
  --dark2: #1a1610;
  --dark3: #332e22;
  --muted: #8a7a5a;
  --font-mono: 'Share Tech Mono', 'Fira Code', 'Courier New', monospace;
  --nav-h: 64px;
  --anchor-h: 40px;
  --radius: 0px;
  --transition: 0.25s ease;
}

/* ========== 重置 ========== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body { font-family: var(--font-mono); background: var(--dark); color: var(--cream); line-height: 1.6; overflow-x: hidden; }
a { color: var(--caramel); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--cream); }
img { max-width: 100%; display: block; }
ul, ol { list-style: none; }

/* ========== Grain 胶片颗粒 ========== */
.grain-overlay {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 9999;
  opacity: 0.06;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='200' height='200'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='200' height='200' filter='url(%23noise)' opacity='1'/%3E%3C/svg%3E");
  background-size: 200px 200px;
  animation: grainShift 0.15s steps(1) infinite;
}
@keyframes grainShift {
  0%   { background-position: 0 0; }
  25%  { background-position: -40px 20px; }
  50%  { background-position: 20px -30px; }
  75%  { background-position: -10px 40px; }
  100% { background-position: 30px -10px; }
}

/* ========== 光晕 light leak ========== */
.lightleak {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 3px;
  pointer-events: none;
  z-index: 9998;
  background: linear-gradient(90deg, transparent 0%, #f5e6c8 30%, #d4a574 55%, transparent 100%);
  opacity: 0.5;
  animation: leakMove 6s ease-in-out infinite alternate;
}
@keyframes leakMove {
  0%   { opacity: 0.2; transform: scaleX(0.6) translateX(-20%); }
  100% { opacity: 0.6; transform: scaleX(1.1) translateX(10%); }
}

/* ========== 顶部导航 ========== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 200;
  background: rgba(38, 33, 23, 0.96);
  border-bottom: 1px solid var(--dark3);
  backdrop-filter: blur(6px);
  height: var(--nav-h);
}
.header-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.nav-group {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex: 1;
}
.nav-group--right { justify-content: flex-end; }
.nav-pill {
  display: inline-flex;
  align-items: center;
  padding: 0.45rem 1rem;
  border-radius: 999px;
  border: 1px solid var(--dark3);
  color: var(--cream);
  font-size: 0.78rem;
  letter-spacing: 0.05em;
  white-space: nowrap;
  transition: background var(--transition), border-color var(--transition), transform var(--transition);
  min-height: 40px;
  line-height: 1.3;
  font-family: var(--font-mono);
}
.nav-pill:hover {
  background: var(--dark3);
  border-color: var(--caramel);
  color: var(--caramel);
  transform: translateY(-1px);
}
.nav-cta {
  background: var(--caramel);
  border-color: var(--caramel);
  color: var(--dark);
  font-weight: 700;
}
.nav-cta:hover {
  background: var(--cream);
  border-color: var(--cream);
  color: var(--dark);
}
.brand-center {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}
.brand-logo { height: 36px; width: auto; }
.brand-text {
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--caramel);
  white-space: nowrap;
}

/* ========== 二级粘性锚点条 ========== */
.anchor-bar {
  position: sticky;
  top: var(--nav-h);
  z-index: 190;
  background: var(--dark2);
  border-bottom: 1px solid var(--dark3);
  height: var(--anchor-h);
  overflow-x: auto;
  scrollbar-width: none;
}
.anchor-bar::-webkit-scrollbar { display: none; }
.anchor-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 100%;
  display: flex;
  align-items: center;
  gap: 0.25rem;
}
.anchor-link {
  font-size: 0.72rem;
  color: var(--muted);
  padding: 0.3rem 0.8rem;
  white-space: nowrap;
  border-radius: 999px;
  transition: color var(--transition), background var(--transition), transform var(--transition);
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  font-family: var(--font-mono);
}
.anchor-link:hover {
  color: var(--caramel);
  background: var(--dark3);
  transform: translateY(-1px);
}

/* ========== scroll-margin for sections ========== */
section[id] {
  scroll-margin-top: calc(var(--nav-h) + var(--anchor-h) + 8px);
}

/* ========== Hero ========== */
.hero-section {
  position: relative;
  min-height: 45vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  text-align: center;
  background: var(--dark2);
}
.hero-bg {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(160deg, rgba(212,165,116,0.15) 0%, transparent 50%),
    linear-gradient(to bottom, var(--dark2), var(--dark));
  filter: sepia(0.3) contrast(1.1) saturate(0.8);
}
.hero-vhs-lines {
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(
    to bottom,
    transparent 0px,
    transparent 3px,
    rgba(245,230,200,0.03) 3px,
    rgba(245,230,200,0.03) 4px
  );
  animation: vhsTrack 8s linear infinite;
}
@keyframes vhsTrack {
  0%   { transform: translateY(0) skewX(0deg); }
  2%   { transform: translateY(-2px) skewX(0.3deg); }
  4%   { transform: translateY(0) skewX(0deg); }
  96%  { transform: translateY(0) skewX(0deg); }
  98%  { transform: translateY(3px) skewX(-0.2deg); }
  100% { transform: translateY(0) skewX(0deg); }
}
.hero-content {
  position: relative;
  z-index: 10;
  padding: 3rem 1.5rem;
  max-width: 720px;
  animation: fadeUp 0.8s ease both;
}
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(24px); }
  to   { opacity: 1; transform: translateY(0); }
}
.hero-badge {
  display: inline-block;
  background: var(--caramel);
  color: var(--dark);
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  padding: 0.35rem 1rem;
  border-radius: 999px;
  margin-bottom: 1rem;
  min-height: 28px;
  line-height: 1.4;
}
.hero-h1 {
  font-size: clamp(1.8rem, 5vw, 3rem);
  font-weight: 700;
  color: var(--cream);
  letter-spacing: 0.06em;
  line-height: 1.25;
  margin-bottom: 0.8rem;
}
.hero-sub {
  font-size: 0.95rem;
  color: var(--muted);
  max-width: 520px;
  margin: 0 auto 1.6rem;
  line-height: 1.7;
}
.hero-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--caramel);
  color: var(--dark);
  padding: 0.75rem 2rem;
  border-radius: 999px;
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  transition: background var(--transition), transform var(--transition);
  min-height: 48px;
  font-family: var(--font-mono);
}
.hero-btn:hover {
  background: var(--cream);
  color: var(--dark);
  transform: translateY(-2px);
}
.hero-float-tags {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 5;
}
.float-tag {
  position: absolute;
  font-size: 0.65rem;
  letter-spacing: 0.15em;
  color: var(--caramel);
  opacity: 0.45;
  border: 1px solid var(--dark3);
  padding: 0.3rem 0.7rem;
  background: rgba(38,33,23,0.6);
  animation: tagFloat 5s ease-in-out infinite;
  min-height: 28px;
  display: inline-flex;
  align-items: center;
}
.ft1 { top: 20%; left: 8%; animation-delay: 0s; }
.ft2 { bottom: 25%; left: 12%; animation-delay: 1.5s; }
.ft3 { top: 30%; right: 8%; animation-delay: 0.8s; }
@keyframes tagFloat {
  0%, 100% { transform: translateY(0); }
  50%       { transform: translateY(-6px); }
}

/* ========== 内容区布局 ========== */
.content-section {
  max-width: 1280px;
  margin: 0 auto;
  padding: 3rem 1.5rem;
  display: flex;
  gap: 2.5rem;
  align-items: flex-start;
}

/* ========== 侧边栏（左） ========== */
.content-aside {
  width: 200px;
  flex-shrink: 0;
  position: sticky;
  top: calc(var(--nav-h) + var(--anchor-h) + 16px);
  background: var(--dark2);
  border: 1px solid var(--dark3);
  padding: 1.25rem;
  animation: fadeUp 0.9s ease 0.2s both;
}
.aside-label {
  font-size: 0.65rem;
  letter-spacing: 0.2em;
  color: var(--muted);
  border-bottom: 1px solid var(--dark3);
  padding-bottom: 0.5rem;
  margin-bottom: 0.8rem;
}
.aside-nav li { margin-bottom: 0.4rem; }
.aside-nav a {
  font-size: 0.75rem;
  color: var(--muted);
  letter-spacing: 0.05em;
  display: flex;
  align-items: center;
  padding: 0.3rem 0 0.3rem 0.5rem;
  border-left: 2px solid transparent;
  min-height: 32px;
  transition: color var(--transition), border-color var(--transition);
}
.aside-nav a:hover {
  color: var(--caramel);
  border-left-color: var(--caramel);
}
.aside-tape {
  margin-top: 1.5rem;
  display: flex;
  align-items: center;
  gap: 4px;
}
.tape-reel {
  width: 24px; height: 24px;
  border: 2px solid var(--dark3);
  border-radius: 50%;
  position: relative;
}
.tape-reel::after {
  content: '';
  position: absolute;
  inset: 5px;
  background: var(--dark3);
  border-radius: 50%;
}
.tape-strip {
  flex: 1;
  height: 6px;
  background: repeating-linear-gradient(
    90deg,
    var(--dark3) 0px, var(--dark3) 4px,
    transparent 4px, transparent 8px
  );
}

/* ========== 正文主容器 ========== */
.content-main {
  flex: 1;
  min-width: 0;
  animation: fadeUp 0.9s ease 0.1s both;
}
.page-content { font-size: 1rem; line-height: 1.75; color: var(--cream); }

/* 正文内各 article 样式 */
.page-content article {
  padding: 2.5rem 0;
  border-bottom: 1px solid var(--dark3);
}
.page-content article:last-child { border-bottom: none; }

/* figure 与 aside 交错（契约需要） */
.page-content article > figure {
  margin: 1.5rem 0;
  background: var(--dark2);
  border: 1px solid var(--dark3);
  padding: 1rem;
}
.page-content article > aside {
  background: var(--dark3);
  border-left: 3px solid var(--caramel);
  padding: 1rem 1.25rem;
  margin: 1.5rem 0;
  font-size: 0.9rem;
  color: var(--muted);
}

/* 正文标题 */
.page-content h2 {
  font-size: clamp(1.15rem, 2.5vw, 1.5rem);
  font-weight: 700;
  color: var(--caramel);
  letter-spacing: 0.06em;
  margin-bottom: 0.4rem;
  line-height: 1.3;
}
.page-content .subtitle,
.page-content .subhead,
.page-content .lead,
.page-content .desc {
  font-size: 0.9rem;
  color: var(--muted);
  margin-bottom: 1rem;
  letter-spacing: 0.04em;
}
.page-content h3 {
  font-size: 1rem;
  color: var(--cream);
  letter-spacing: 0.05em;
  margin: 1.2rem 0 0.5rem;
}
.page-content p {
  margin-bottom: 0.9rem;
  font-size: 1rem;
}
.page-content ul, .page-content ol {
  list-style: disc;
  padding-left: 1.5rem;
  margin-bottom: 0.9rem;
}
.page-content ol { list-style: decimal; }
.page-content li { margin-bottom: 0.35rem; }
.page-content a { color: var(--caramel); border-bottom: 1px solid transparent; }
.page-content a:hover { border-bottom-color: var(--caramel); }
.page-content strong { color: var(--cream); font-weight: 700; }
.page-content code {
  font-family: var(--font-mono);
  background: var(--dark3);
  color: var(--caramel);
  padding: 0.1em 0.4em;
  font-size: 0.88em;
  letter-spacing: 0.04em;
}
.page-content pre {
  background: var(--dark2);
  border: 1px solid var(--dark3);
  padding: 1rem;
  overflow-x: auto;
  margin-bottom: 1rem;
  font-size: 0.85rem;
  color: var(--caramel);
  line-height: 1.6;
}
.page-content blockquote {
  border-left: 3px solid var(--caramel);
  padding: 0.8rem 1.2rem;
  background: var(--dark2);
  margin: 1rem 0;
  color: var(--muted);
  font-style: italic;
}
.page-content table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 1rem;
  font-size: 0.88rem;
}
.page-content th, .page-content td {
  border: 1px solid var(--dark3);
  padding: 0.6rem 0.9rem;
  text-align: left;
}
.page-content th {
  background: var(--dark3);
  color: var(--caramel);
  letter-spacing: 0.05em;
}

/* ========== 页脚 ========== */
.site-footer {
  background: var(--dark2);
  border-top: 1px solid var(--dark3);
  margin-top: 3rem;
}
.footer-top {
  max-width: 1280px;
  margin: 0 auto;
  padding: 3rem 1.5rem 2rem;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 2.5rem;
  align-items: start;
}
.footer-brand-big {
  font-size: clamp(2rem, 6vw, 4rem);
  font-weight: 700;
  color: var(--caramel);
  letter-spacing: 0.15em;
  line-height: 1;
  margin-bottom: 0.8rem;
  opacity: 0.9;
}
.footer-brand-desc {
  font-size: 0.8rem;
  color: var(--muted);
  line-height: 1.6;
  max-width: 280px;
}
.footer-nav-col nav dl dt {
  margin-bottom: 0.5rem;
}
.footer-nav-col nav dl dt a {
  font-size: 0.8rem;
  color: var(--muted);
  letter-spacing: 0.05em;
  transition: color var(--transition);
  min-height: 40px;
  display: inline-flex;
  align-items: center;
}
.footer-nav-col nav dl dt a:hover { color: var(--caramel); }
.footer-contact-col address {
  font-style: normal;
  margin-bottom: 1rem;
}
.contact-item {
  display: flex;
  flex-direction: column;
  margin-bottom: 0.6rem;
}
.contact-label {
  font-size: 0.65rem;
  letter-spacing: 0.15em;
  color: var(--muted);
  margin-bottom: 0.1rem;
}
.contact-item a,
.contact-item span {
  font-size: 0.8rem;
  color: var(--cream);
}
.footer-link-list {
  list-style: none;
  padding: 0;
  margin-top: 0.5rem;
}
.footer-link-list li { margin-bottom: 0.4rem; }
.footer-link-list li a {
  font-size: 0.78rem;
  color: var(--muted);
  min-height: 40px;
  display: inline-flex;
  align-items: center;
}
.footer-link-list li a:hover { color: var(--caramel); }

/* 胶片条纹装饰 */
.footer-film-strip {
  display: flex;
  flex-direction: column;
  gap: 6px;
  align-items: center;
  padding: 0.5rem;
}
.film-hole {
  width: 20px; height: 14px;
  border: 2px solid var(--dark3);
  border-radius: 2px;
}
.film-frame {
  width: 48px; height: 36px;
  border: 1px solid var(--dark3);
  background: var(--dark);
}
.footer-bottom {
  max-width: 1280px;
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-top: 1px solid var(--dark3);
  flex-wrap: wrap;
  gap: 0.5rem;
}
.footer-copy {
  font-size: 0.72rem;
  color: var(--muted);
  letter-spacing: 0.05em;
}
.footer-tagline {
  font-size: 0.65rem;
  color: var(--dark3);
  letter-spacing: 0.12em;
}

/* ========== Stagger 动画 ========== */
.aside-nav li {
  opacity: 0;
  transform: translateX(-8px);
  animation: fadeSlide 0.4s ease forwards;
}
.aside-nav li:nth-child(1) { animation-delay: 0.3s; }
.aside-nav li:nth-child(2) { animation-delay: 0.4s; }
.aside-nav li:nth-child(3) { animation-delay: 0.5s; }
.aside-nav li:nth-child(4) { animation-delay: 0.6s; }
.aside-nav li:nth-child(5) { animation-delay: 0.7s; }
.aside-nav li:nth-child(6) { animation-delay: 0.8s; }
.aside-nav li:nth-child(7) { animation-delay: 0.9s; }
@keyframes fadeSlide {
  to { opacity: 1; transform: translateX(0); }
}

/* ========== 断点：平板 ========== */
@media (max-width: 900px) {
  .footer-top {
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }
  .content-aside {
    width: 160px;
  }
  .nav-group { gap: 0.3rem; }
  .nav-pill { padding: 0.4rem 0.7rem; font-size: 0.72rem; }
}

/* ========== 断点：移动端 ========== */
@media (max-width: 640px) {
  :root { --nav-h: 56px; --anchor-h: 44px; }
  .header-inner { padding: 0 1rem; gap: 0.5rem; }
  .nav-group--left .nav-pill:not(:first-child) { display: none; }
  .nav-group--right .nav-pill:not(.nav-cta) { display: none; }
  .hero-section { min-height: 45vh; }
  .hero-h1 { font-size: 1.5rem; }
  .content-section {
    flex-direction: column;
    padding: 1.5rem 1rem;
    gap: 1.5rem;
  }
  .content-aside {
    width: 100%;
    position: static;
  }
  .aside-tape { display: none; }
  .footer-top {
    grid-template-columns: 1fr;
    gap: 1.5rem;
    padding: 2rem 1rem 1.5rem;
  }
  .footer-meta-col { display: none; }
  .footer-film-strip { flex-direction: row; }
  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
    padding: 0.8rem 1rem;
  }
  .hero-float-tags { display: none; }
  .anchor-inner { padding: 0 0.75rem; gap: 0; }
  .anchor-link { padding: 0.25rem 0.6rem; font-size: 0.68rem; }
}

/* ========== prefers-reduced-motion ========== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
  html { scroll-behavior: auto; }
}