:root {
  --color-bg: #E4EDFB;
  --color-panel: #F3F8FF;
  --color-panel-raised: #D5E3F7;
  --color-border: #B9CDEA;
  --color-accent: #2036E6;
  --color-accent-dark: #14239E;
  --color-violet: #8B45E6;
  --color-text: #101A33;
  --color-text-muted: #4A5876;
  --color-success: #0E9F6E;
  --color-warning: #D97706;
  --color-error: #DC2626;
  --color-white: #FFFFFF;
  --color-flag-red: #D3484A;
  --color-flag-blue: #2B4C9B;
  --color-flag-black: #2A2A31;
  --color-flag-gold: #F2C94C;
  --color-overlay: color-mix(in srgb, var(--color-text) 24%, transparent);
  --color-grid: color-mix(in srgb, var(--color-accent) 9%, transparent);
  --color-accent-soft: color-mix(in srgb, var(--color-accent) 8%, var(--color-panel));
  --color-success-soft: color-mix(in srgb, var(--color-success) 12%, var(--color-panel));
  --shadow-window-a: color-mix(in srgb, var(--color-accent-dark) 10%, transparent);
  --shadow-window-b: color-mix(in srgb, var(--color-accent-dark) 26%, transparent);
  --shadow-card: color-mix(in srgb, var(--color-accent-dark) 16%, transparent);
  --font-display: 'Inter', 'Noto Sans SC', 'Noto Sans JP', 'Noto Sans KR', -apple-system, 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-body: 'Inter', 'Noto Sans SC', 'Noto Sans JP', 'Noto Sans KR', -apple-system, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --font-mono: 'JetBrains Mono', 'SFMono-Regular', 'Menlo', 'Consolas', monospace;
  --radius-xs: 6px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 14px;
  --radius-pill: 999px;
  --header-height: 64px;
  --gutter: clamp(16px, 4vw, 32px);
  --content-width: 1160px;
  --wide-width: 1280px;
  --reading-width: 780px;
  --section-space: clamp(64px, 9vw, 112px);
  --focus-ring: 2px solid var(--color-accent);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 16px);
  background: var(--color-bg);
}

html.nav-open {
  overflow: hidden;
}

body {
  margin: 0;
  min-width: 320px;
  overflow-x: clip;
  color: var(--color-text);
  background: var(--color-bg);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

main,
section,
article,
aside,
header,
footer,
nav {
  min-width: 0;
}

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

img {
  height: auto;
}

button,
input,
select,
textarea {
  color: inherit;
  font: inherit;
}

button,
summary,
[role="tab"] {
  cursor: pointer;
}

a {
  color: var(--color-accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
}

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

button {
  border: 0;
}

a:focus-visible,
button:focus-visible,
summary:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible,
[role="tab"]:focus-visible {
  outline: var(--focus-ring);
  outline-offset: 3px;
}

h1,
h2,
h3,
h4,
p,
ul,
ol,
blockquote,
pre,
figure {
  margin-top: 0;
}

h1,
h2,
h3,
h4 {
  color: var(--color-text);
  font-family: var(--font-display);
  line-height: 1.16;
  text-wrap: balance;
}

h1 {
  margin-bottom: 24px;
  font-size: clamp(52px, 5.2vw, 68px);
  font-weight: 900;
  letter-spacing: -0.02em;
}

h2 {
  margin-bottom: 20px;
  font-size: clamp(32px, 4vw, 48px);
  font-weight: 850;
  letter-spacing: -0.018em;
}

h3 {
  margin-bottom: 14px;
  font-size: clamp(21px, 2.4vw, 28px);
  font-weight: 800;
  letter-spacing: -0.01em;
}

h4 {
  margin-bottom: 10px;
  font-size: 18px;
  font-weight: 750;
}

p {
  margin-bottom: 1.15em;
}

ul,
ol {
  padding-left: 1.35em;
}

strong {
  font-weight: 750;
}

small,
.text-muted {
  color: var(--color-text-muted);
}

code,
kbd,
samp {
  font-family: var(--font-mono);
}

:not(pre) > code {
  overflow-wrap: anywhere;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xs);
  background: var(--color-panel-raised);
  padding: 0.12em 0.38em;
  color: var(--color-accent-dark);
}

pre {
  max-width: 100%;
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-text);
  padding: 18px;
  color: var(--color-panel);
  -webkit-overflow-scrolling: touch;
}

pre code {
  white-space: pre;
  overflow-wrap: normal;
}

hr {
  border: 0;
  border-top: 1px solid var(--color-border);
}

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

.no-break {
  white-space: nowrap;
}

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

.wrap {
  max-width: calc(var(--content-width) + var(--gutter) * 2);
}

.wrap-wide {
  max-width: calc(var(--wide-width) + var(--gutter) * 2);
}

.reading-wrap {
  max-width: calc(var(--reading-width) + var(--gutter) * 2);
}

.section {
  padding-top: var(--section-space);
  padding-bottom: var(--section-space);
}

.section-compact {
  padding-top: calc(var(--section-space) * 0.62);
  padding-bottom: calc(var(--section-space) * 0.62);
}

.section-heading {
  max-width: 780px;
  margin: 0 auto 42px;
  text-align: center;
}

.eyebrow {
  margin-bottom: 12px;
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.13em;
  text-transform: uppercase;
}

.lead {
  color: var(--color-text-muted);
  font-size: clamp(18px, 2vw, 22px);
  line-height: 1.65;
}

.panel,
.card {
  min-width: 0;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-panel);
}

.panel {
  padding: clamp(22px, 4vw, 42px);
}

.card {
  padding: 24px;
  transition: border-color 180ms ease, box-shadow 180ms ease, transform 180ms ease;
}

.card:hover {
  border-color: color-mix(in srgb, var(--color-accent) 42%, var(--color-border));
  box-shadow: 0 18px 38px -28px var(--shadow-card);
}

.btn {
  display: inline-flex;
  min-width: 24px;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  gap: 9px;
  border: 1.5px solid transparent;
  border-radius: var(--radius-sm);
  padding: 0 28px;
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 750;
  line-height: 1;
  text-align: center;
  text-decoration: none;
  transition: transform 160ms ease, background-color 160ms ease, border-color 160ms ease, color 160ms ease, box-shadow 160ms ease;
}

.btn:hover {
  transform: translateY(-1px);
  text-decoration: none;
}

.btn-primary {
  background: var(--color-accent);
  color: var(--color-white);
  box-shadow: 0 10px 22px -10px color-mix(in srgb, var(--color-accent) 55%, transparent);
}

.btn-primary:hover {
  background: var(--color-accent-dark);
  color: var(--color-white);
}

.btn-secondary {
  border-color: var(--color-border);
  background: var(--color-panel);
  color: var(--color-accent);
}

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

.btn-danger {
  background: var(--color-error);
  color: var(--color-white);
}

.btn-small {
  min-height: 38px;
  padding-inline: 17px;
  font-size: 14px;
}

.btn[aria-disabled="true"],
.btn:disabled {
  cursor: not-allowed;
  opacity: 0.55;
  transform: none;
}

.badge,
.tag {
  display: inline-flex;
  max-width: 100%;
  min-height: 26px;
  align-items: center;
  gap: 7px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  background: var(--color-panel);
  padding: 3px 11px;
  color: var(--color-text-muted);
  font-size: 12px;
  font-weight: 700;
  line-height: 1.4;
  text-overflow: ellipsis;
}

.badge-dot {
  width: 7px;
  height: 7px;
  flex: 0 0 7px;
  border-radius: 50%;
  background: var(--color-accent);
}

.badge-success {
  border-color: color-mix(in srgb, var(--color-success) 35%, var(--color-border));
  background: var(--color-success-soft);
  color: var(--color-success);
}

.site-header {
  position: sticky;
  z-index: 80;
  top: 0;
  border-bottom: 1px solid color-mix(in srgb, var(--color-border) 55%, transparent);
  background: color-mix(in srgb, var(--color-bg) 94%, transparent);
  backdrop-filter: blur(14px);
}

.header-inner {
  display: flex;
  width: 100%;
  max-width: var(--wide-width);
  height: var(--header-height);
  align-items: center;
  gap: 30px;
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.site-brand {
  display: inline-flex;
  min-width: max-content;
  min-height: 44px;
  align-items: center;
  gap: 10px;
  color: var(--color-text);
  text-decoration: none;
}

.site-brand:hover {
  color: var(--color-text);
}

.site-brand img {
  width: 30px;
  height: 30px;
  flex: 0 0 30px;
}

.brand-latin {
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 850;
  letter-spacing: -0.01em;
}

.brand-local {
  color: var(--color-text-muted);
  font-size: 14px;
  font-weight: 600;
}

.desktop-nav {
  display: flex;
  height: var(--header-height);
  align-items: stretch;
  gap: 2px;
}

.desktop-nav a {
  position: relative;
  display: flex;
  min-height: 44px;
  align-items: center;
  padding-inline: 11px;
  color: var(--color-text-muted);
  font-size: 14px;
  font-weight: 550;
  text-decoration: none;
}

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

.desktop-nav a.is-active {
  color: var(--color-text);
  font-weight: 750;
}

.desktop-nav a.is-active::after {
  position: absolute;
  right: 11px;
  bottom: -1px;
  left: 11px;
  height: 3px;
  border-radius: 2px 2px 0 0;
  background: var(--color-accent);
  content: "";
}

.header-tools {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-left: auto;
}

.login-link {
  display: inline-flex;
  min-height: 38px;
  align-items: center;
  justify-content: center;
  border: 1.5px solid var(--color-accent);
  border-radius: var(--radius-sm);
  background: var(--color-panel);
  padding-inline: 17px;
  color: var(--color-accent);
  font-size: 14px;
  font-weight: 750;
  text-decoration: none;
}

.login-link:hover {
  background: var(--color-accent);
  color: var(--color-white);
}

.language-picker {
  position: relative;
}

.language-button,
.menu-button {
  display: inline-flex;
  min-width: 44px;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--color-text-muted);
}

.language-button {
  gap: 6px;
  padding-inline: 10px;
  font-size: 13px;
}

.language-menu {
  position: absolute;
  z-index: 95;
  top: calc(100% + 8px);
  right: 0;
  display: none;
  width: 168px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-panel);
  box-shadow: 0 18px 40px -24px var(--shadow-card);
  padding: 6px;
}

.language-picker.is-open .language-menu {
  display: block;
}

.language-menu a {
  display: flex;
  min-height: 42px;
  align-items: center;
  border-radius: var(--radius-xs);
  padding-inline: 12px;
  color: var(--color-text-muted);
  font-size: 13px;
  text-decoration: none;
}

.language-menu a:hover,
.language-menu a[aria-current="true"] {
  background: var(--color-panel-raised);
  color: var(--color-text);
}

.menu-button {
  display: none;
  flex-direction: column;
  gap: 5px;
}

.menu-button span {
  width: 20px;
  height: 2px;
  border-radius: var(--radius-pill);
  background: var(--color-text);
  transition: transform 160ms ease, opacity 160ms ease;
}

.menu-button[aria-expanded="true"] span:first-child {
  transform: translateY(7px) rotate(45deg);
}

.menu-button[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.menu-button[aria-expanded="true"] span:last-child {
  transform: translateY(-7px) rotate(-45deg);
}

.mobile-nav {
  position: fixed;
  z-index: 90;
  top: var(--header-height);
  right: 0;
  left: 0;
  display: none;
  max-height: calc(100dvh - var(--header-height));
  overflow-y: auto;
  overscroll-behavior: contain;
  border-top: 1px solid var(--color-border);
  background: var(--color-panel);
  padding: 10px var(--gutter) calc(18px + env(safe-area-inset-bottom, 0px));
}

.mobile-nav.is-open {
  display: block;
}

.mobile-nav a {
  display: flex;
  width: 100%;
  min-height: 48px;
  align-items: center;
  border-bottom: 1px solid color-mix(in srgb, var(--color-border) 54%, transparent);
  padding: 11px 8px;
  color: var(--color-text);
  text-decoration: none;
}

.mobile-nav a.is-active {
  color: var(--color-accent);
  font-weight: 750;
}

.mobile-language-title {
  margin: 18px 8px 5px;
  color: var(--color-text-muted);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.nav-veil {
  position: fixed;
  z-index: 70;
  inset: var(--header-height) 0 0;
  display: none;
  background: var(--color-overlay);
}

.nav-veil.is-open {
  display: block;
}

.site-footer {
  border-top: 1px solid var(--color-border);
  background: var(--color-panel-raised);
}

.footer-grid {
  display: grid;
  grid-template-columns: minmax(220px, 1.2fr) repeat(3, minmax(150px, 1fr));
  gap: 38px;
  padding-top: 56px;
  padding-bottom: 42px;
}

.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--color-text);
  text-decoration: none;
}

.footer-brand img {
  width: 34px;
  height: 34px;
}

.footer-brand-copy {
  max-width: 310px;
  margin-top: 16px;
  color: var(--color-text-muted);
  font-size: 14px;
}

.footer-title {
  margin-bottom: 14px;
  color: var(--color-text);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.06em;
}

.footer-links {
  display: grid;
  gap: 7px;
}

.footer-links a {
  display: inline-flex;
  min-height: 30px;
  align-items: center;
  color: var(--color-text-muted);
  font-size: 14px;
  text-decoration: none;
}

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

.footer-bottom {
  display: flex;
  min-height: 68px;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  border-top: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-size: 13px;
}

.footer-legal,
.footer-languages {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
}

.footer-legal a,
.footer-languages a {
  min-height: 24px;
  color: var(--color-text-muted);
  text-decoration: none;
}

.reveal {
  transition: opacity 560ms ease, transform 560ms ease;
}

.reveal.pending {
  opacity: 0;
  transform: translateY(16px);
}

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

.prose {
  min-width: 0;
  color: var(--color-text);
}

.prose h2,
.prose h3 {
  scroll-margin-top: calc(var(--header-height) + 84px);
}

.prose h2 {
  margin-top: 2.1em;
}

.prose h3 {
  margin-top: 1.7em;
}

.prose a {
  overflow-wrap: anywhere;
}

.prose img {
  border-radius: var(--radius-sm);
}

.prose > *:last-child {
  margin-bottom: 0;
}

@media (max-width: 1080px) {
  .desktop-nav a {
    padding-inline: 8px;
    font-size: 13px;
  }

  .desktop-nav a.is-active::after {
    right: 8px;
    left: 8px;
  }

  .language-button {
    display: none;
  }
}

@media (max-width: 900px) {
  .desktop-nav,
  .language-picker {
    display: none;
  }

  .header-tools {
    margin-left: auto;
  }

  .menu-button {
    display: inline-flex;
  }

  .footer-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 768px) {
  h1 {
    font-size: clamp(32px, 9vw, 40px);
    line-height: 1.12;
  }

  h2 {
    font-size: clamp(27px, 7vw, 36px);
  }

  .section {
    padding-top: 64px;
    padding-bottom: 64px;
  }

  .decorative-tilt,
  .tilt-card {
    transform: none;
  }
}

@media (max-width: 640px) {
  :root {
    --header-height: 60px;
    --gutter: 16px;
  }

  body {
    font-size: 15px;
  }

  .header-inner {
    gap: 8px;
  }

  .site-brand img {
    width: 28px;
    height: 28px;
    flex-basis: 28px;
  }

  .brand-latin {
    font-size: 17px;
  }

  .brand-local {
    display: none;
  }

  .login-link {
    min-height: 36px;
    padding-inline: 12px;
  }

  .btn {
    min-height: 46px;
    padding-inline: 20px;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .footer-bottom {
    align-items: flex-start;
    flex-direction: column;
    padding-top: 20px;
    padding-bottom: 24px;
  }

  .card,
  .panel {
    padding: 20px;
  }

  .decorative-tilt,
  [class*="tilt"] {
    transform: none;
  }
}

@media (max-width: 370px) {
  .login-link {
    padding-inline: 10px;
    font-size: 13px;
  }

  .header-tools {
    gap: 4px;
  }

  .site-brand {
    gap: 7px;
  }
}

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

  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation: none !important;
    transition-duration: 0.01ms !important;
  }

  .reveal,
  .reveal.pending {
    opacity: 1;
    transform: none;
  }
}