:root {
  --paper: #F5F1E8;
  --ink: #1E1C19;
  --blue: #006DFF;
  --orange: #FF6A00;
  --blue-soft: #B0D0FF;
  --orange-soft: #FFE0C2;
  --gray: #6B675F;
  --success: #0FA36B;
  --danger: #E0322D;
  --line: #D8D2C4;
  --font-sans: "Inter", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-serif: "Source Serif Pro", "Noto Serif SC", Georgia, serif;
  --header-width: 220px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
}

h1,
h2,
h3,
h4 {
  margin: 0 0 0.6em;
  color: var(--ink);
  font-family: var(--font-sans);
  font-weight: 900;
  line-height: 1.15;
}

h1 {
  font-size: clamp(1.9rem, 4vw, 2.8rem);
}

h2 {
  font-size: clamp(1.4rem, 3vw, 2rem);
}

h3 {
  font-size: clamp(1.1rem, 2vw, 1.35rem);
}

p {
  margin: 0 0 1em;
}

a {
  color: var(--blue);
}

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

button {
  font-family: inherit;
}

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

#main-content {
  display: block;
  min-height: 70vh;
  scroll-margin-top: 24px;
}

@media (min-width: 861px) {
  body {
    margin-left: var(--header-width);
  }
}

.skip-link {
  position: fixed;
  top: -100px;
  left: 8px;
  z-index: 300;
  padding: 10px 16px;
  background: var(--orange);
  color: #fff;
  font-weight: 700;
  text-decoration: none;
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 8px;
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 100;
  display: flex;
  flex-direction: column;
  width: var(--header-width);
  height: 100vh;
  height: 100dvh;
  background:
    linear-gradient(180deg, rgba(0, 109, 255, 0.08), transparent 180px),
    repeating-linear-gradient(45deg, rgba(30, 28, 25, 0.025) 0 1px, transparent 1px 9px),
    var(--paper);
  border-right: 1px solid var(--blue);
}

.header-inner {
  display: flex;
  flex-direction: column;
  gap: 32px;
  width: 100%;
  padding: 24px 20px;
  overflow-y: auto;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 0;
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--line);
}

.brand-mark {
  padding: 2px 6px;
  background: var(--blue-soft);
  color: var(--blue);
  font-size: 2rem;
  font-weight: 900;
  line-height: 1;
}

.brand:hover .brand-mark {
  background: var(--blue);
  color: var(--paper);
}

.brand-name {
  font-size: 1rem;
  font-weight: 800;
  line-height: 1.25;
}

.nav-site {
  display: block;
}

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

.nav-item {
  margin: 1px 0;
}

.nav-link {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 10px 8px 10px 12px;
  color: var(--ink);
  text-decoration: none;
  font-weight: 600;
  border-left: 3px solid transparent;
}

.nav-index {
  min-width: 1.6em;
  color: var(--orange);
  font-family: var(--font-serif);
  font-size: 0.78rem;
  font-style: italic;
}

.nav-label {
  font-size: 1rem;
}

.nav-link:hover {
  background: var(--blue-soft);
  border-left-color: var(--blue);
}

.nav-link[aria-current="page"] {
  background: rgba(255, 255, 255, 0.5);
  border-left-color: var(--orange);
  color: var(--blue);
}

.nav-link[aria-current="page"] .nav-label {
  font-weight: 900;
}

.login-state {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: auto;
  padding: 10px 8px;
  background: rgba(255, 255, 255, 0.35);
  border: 1px solid var(--line);
  color: var(--gray);
  font-size: 0.82rem;
}

.state-dot {
  width: 8px;
  height: 8px;
  background: var(--success);
  border-radius: 50%;
  box-shadow: 0 0 0 4px rgba(15, 163, 107, 0.14);
}

.state-text {
  line-height: 1.2;
}

.nav-toggle {
  display: none;
}

.nav-toggle-box {
  position: relative;
  display: inline-block;
  width: 18px;
  height: 12px;
}

.nav-toggle-box::before,
.nav-toggle-box::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  background: var(--ink);
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.nav-toggle-box::before {
  top: 0;
}

.nav-toggle-box::after {
  bottom: 0;
}

.nav-toggle-line {
  position: absolute;
  top: 5px;
  left: 0;
  width: 18px;
  height: 2px;
  background: var(--ink);
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.site-header[data-open="true"] .nav-toggle-box::before {
  transform: translateY(5px) rotate(45deg);
}

.site-header[data-open="true"] .nav-toggle-box::after {
  transform: translateY(-5px) rotate(-45deg);
}

.site-header[data-open="true"] .nav-toggle-line {
  opacity: 0;
}

.nav-toggle-label {
  color: var(--ink);
  font-size: 0.9rem;
  font-weight: 700;
}

@media (max-width: 860px) {
  body {
    margin-left: 0;
  }

  .site-header {
    position: sticky;
    top: 0;
    display: block;
    width: 100%;
    height: auto;
    border-right: 0;
    border-bottom: 1px solid var(--blue);
  }

  .header-inner {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 8px;
    align-items: center;
    padding: 8px 12px;
  }

  .header-inner > .brand {
    order: 1;
    padding: 4px 0;
    border-bottom: 0;
  }

  .header-inner > .nav-toggle {
    order: 2;
  }

  .header-inner > .nav-site {
    order: 3;
  }

  .header-inner > .login-state {
    display: none;
  }

  .brand-mark {
    font-size: 1.3rem;
  }

  .brand-name {
    font-size: 0.9rem;
  }

  .nav-toggle {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    min-height: 48px;
    padding: 8px 12px;
    background: var(--paper);
    border: 1px solid var(--blue);
    cursor: pointer;
  }

  .nav-toggle:hover {
    background: var(--blue-soft);
  }

  .nav-site {
    display: none;
    width: 100%;
  }

  .site-header[data-open="true"] .nav-site {
    display: block;
    grid-column: 1 / -1;
    margin-top: 4px;
    padding-top: 8px;
    border-top: 1px solid var(--line);
  }

  .nav-list {
    padding-bottom: 8px;
  }

  .nav-link {
    padding: 12px 8px;
  }
}

.site-footer {
  padding: clamp(28px, 6vw, 64px) clamp(20px, 4vw, 48px) 20px;
  background: var(--ink);
  color: var(--paper);
}

.footer-inner {
  display: grid;
  grid-template-columns: 1.5fr 0.8fr 1.4fr;
  gap: 32px;
  max-width: 1280px;
  margin: 0 auto;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-mark {
  align-self: flex-start;
  padding: 4px 8px;
  background: var(--paper);
  color: var(--orange);
  font-size: 2rem;
  font-weight: 900;
  line-height: 1;
}

.footer-trust {
  max-width: 300px;
  margin: 0;
  color: var(--blue-soft);
  font-size: 0.9rem;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding-left: 24px;
  border-left: 1px solid rgba(245, 241, 232, 0.2);
}

.footer-link {
  color: var(--paper);
  font-weight: 600;
  text-decoration: none;
}

.footer-link:hover {
  color: var(--orange);
}

.footer-meta {
  display: flex;
  flex-direction: column;
  gap: 4px;
  color: rgba(245, 241, 232, 0.78);
  font-size: 0.85rem;
}

.footer-meta p {
  margin: 0;
}

.back-top {
  align-self: flex-start;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 48px;
  margin-top: 8px;
  padding: 8px 12px;
  background: transparent;
  border: 1px solid var(--blue-soft);
  color: var(--paper);
  cursor: pointer;
}

.back-top:hover {
  background: var(--blue);
  border-color: var(--blue);
}

.footer-bottom {
  max-width: 1280px;
  margin: 24px auto 0;
  padding-top: 16px;
  border-top: 1px solid rgba(245, 241, 232, 0.18);
  color: rgba(245, 241, 232, 0.55);
  font-size: 0.78rem;
}

@media (max-width: 1024px) and (min-width: 861px) {
  .footer-inner {
    grid-template-columns: 1fr 1fr;
  }

  .footer-brand {
    grid-column: 1 / -1;
  }
}

@media (max-width: 860px) {
  .footer-inner {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .footer-links {
    flex-direction: row;
    flex-wrap: wrap;
    padding-left: 0;
    border-left: 0;
  }
}

.container {
  max-width: 1120px;
  margin-right: auto;
  margin-left: auto;
  padding-right: 24px;
  padding-left: 24px;
}

.section {
  padding: clamp(48px, 7vw, 96px) 0;
}

.grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 24px;
}

@media (max-width: 860px) {
  .grid {
    grid-template-columns: repeat(6, 1fr);
  }

  .grid > * {
    grid-column: span 6;
  }
}

.card-grid {
  display: grid;
  gap: 20px;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.card {
  padding: 20px;
  background: #fff;
  border: 1px solid var(--line);
  box-shadow: 0 1px 0 rgba(30, 28, 25, 0.03);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(30, 28, 25, 0.08);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 48px;
  padding: 10px 20px;
  border: 2px solid transparent;
  border-radius: 0;
  cursor: pointer;
  font: inherit;
  font-weight: 700;
  text-decoration: none;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn-primary {
  position: relative;
  overflow: hidden;
  background: var(--blue);
  border-color: var(--blue);
  color: #fff;
}

.btn-primary:hover {
  background: #0052CC;
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(0, 109, 255, 0.25);
}

.btn-primary::after {
  content: "";
  position: absolute;
  top: 0;
  left: -150%;
  width: 70%;
  height: 100%;
  background: linear-gradient(105deg, transparent, rgba(255, 255, 255, 0.45), transparent);
  transform: skewX(-20deg);
  transition: left 0.4s ease;
}

.btn-primary:hover::after {
  left: 120%;
}

.btn-secondary {
  background: transparent;
  border-color: var(--ink);
  color: var(--ink);
}

.btn-secondary:hover {
  background: var(--ink);
  color: var(--paper);
}

.tag {
  display: inline-block;
  padding: 2px 8px;
  background: var(--orange-soft);
  border-left: 3px solid var(--orange);
  color: var(--ink);
  font-family: var(--font-serif);
  font-size: 0.85rem;
}

.eyebrow {
  display: block;
  margin-bottom: 8px;
  color: var(--orange);
  font-family: var(--font-serif);
  font-size: 0.9rem;
  font-style: italic;
}

.lead {
  color: var(--gray);
  font-size: 1.1rem;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 24px;
  padding: 0;
  list-style: none;
  font-size: 0.9rem;
}

.breadcrumb a {
  color: var(--blue);
  text-decoration: none;
}

.breadcrumb li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--gray);
}

.article {
  max-width: 720px;
  margin: 0 auto;
}

.article p {
  line-height: 1.7;
}

.divider {
  height: 1px;
  margin: 32px 0;
  border: 0;
  background: var(--line);
}

.image-frame {
  position: relative;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background:
    linear-gradient(135deg, var(--blue-soft) 0, var(--blue-soft) 33%, transparent 33%),
    var(--paper);
  border: 1px solid var(--line);
}

.image-frame::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  opacity: 0.4;
  background:
    linear-gradient(90deg, transparent 49.8%, rgba(0, 109, 255, 0.25) 50%, transparent 50.2%),
    linear-gradient(0deg, transparent 49.8%, rgba(255, 106, 0, 0.2) 50%, transparent 50.2%);
}

.image-frame img {
  position: relative;
  z-index: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.filter-button {
  min-height: 48px;
  padding: 8px 14px;
  background: var(--paper);
  border: 1px solid var(--line);
  color: var(--ink);
  cursor: pointer;
  font: inherit;
  font-size: 0.9rem;
  transition: border-color 0.2s, background 0.2s, color 0.2s;
}

.filter-button:hover {
  border-color: var(--blue);
  color: var(--blue);
}

.filter-button.is-active {
  background: var(--blue);
  border-color: var(--blue);
  color: #fff;
}

.is-hidden {
  display: none !important;
}

[data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.45s ease, transform 0.45s ease;
}

[data-reveal].is-revealed {
  opacity: 1;
  transform: none;
}

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

  body,
  body * {
    animation: none !important;
    transition: none !important;
  }

  [data-reveal] {
    opacity: 1 !important;
    transform: none !important;
  }
}