:root {
  --ink-black: #000000;
  --page-ink: #1a1a1a;
  --paper-white: #ffffff;
  --link-blue: #057dbc;
  --caption-gray: #6b7280;
  --hairline: #e2e8f0;
  --border-strong: #0f172a;
  --sidebar-active-bg: #f0f0f0;
  --nav-kicker-color: #6b7280;
  --meta-date-color: #4b5563;
  --overlay-bg: rgba(0, 0, 0, 0.4);
  --control-bg: #ffffff;
  --control-border: #111827;
  --control-text: #111827;
  --control-active-bg: #111827;
  --control-active-text: #ffffff;
  --font-main: 'Nanum Myeongjo', Georgia, serif;
  --font-display: var(--font-main);
  --font-body: var(--font-main);
  --font-ui: var(--font-main);
  --font-mono: var(--font-main);
  --sidebar-width: 300px;
}

/* Dark theme disabled – light only */

.theme-mode-toggle {
  display: none !important;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html {
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  color: var(--page-ink);
  background: var(--paper-white);
  line-height: 1.5;
}

.layout {
  display: flex;
  min-height: 100vh;
}

.sidebar {
  width: var(--sidebar-width);
  min-width: var(--sidebar-width);
  border-right: 1px solid var(--border-strong);
  background: var(--paper-white);
  position: fixed;
  top: 0;
  left: 0;
  height: 100vh;
  overflow-y: auto;
  z-index: 100;
  transition: transform 0.18s ease-out;
  display: flex;
  flex-direction: column;
  transform: translateX(-100%);
  padding-top: 60px;
}

.sidebar.open {
  transform: translateX(0);
}

.sidebar-header {
  display: flex;
  padding: 20px 12px;
  flex-direction: column;
  align-items: flex-start;
  gap: 6px;
  border-bottom: 1px solid var(--border-strong);
}

.sidebar-logo {
  color: var(--ink-black);
  font-family: Syne, var(--font-ui);
  font-size: 44px;
  font-weight: 400;
  line-height: 33px;
  letter-spacing: -0.35px;
}

.sidebar-label {
  color: var(--ink-black);
  font-family: "Google Sans Flex", var(--font-ui);
  font-size: 12px;
  font-weight: 400;
  line-height: 18px;
  letter-spacing: 1px;
  text-transform: uppercase;
}

.sidebar-section {
  padding: 14px 0 2px;
  border-top: 1px solid var(--hairline);
}

.sidebar-section:first-of-type {
  border-top: 0;
  padding-top: 12px;
}

.sidebar-group-label {
  display: block;
  padding: 0 12px 8px;
  font-family: "Google Sans Flex", var(--font-ui);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--meta-date-color);
}

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

.sidebar-nav li a,
.sidebar-nav li span {
  display: block;
  padding: 12px 12px;
  text-decoration: none;
}

.sidebar-nav li {
  border-left: none;
  padding-left: 0;
  margin-bottom: 0;
}

.sidebar-nav li span {
  opacity: 0.55;
}

.nav-title {
  display: block;
  font-family: var(--font-ui);
  font-size: 14px;
  font-weight: 400;
  color: var(--caption-gray);
  line-height: 1.45;
  letter-spacing: -0.08px;
}

.nav-kicker {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  color: var(--nav-kicker-color);
  letter-spacing: 0.7px;
  display: block;
  line-height: 1.3;
  margin-top: 8px;
}

.sidebar-nav li a:hover .nav-title {
  color: var(--ink-black);
}

.sidebar-nav li a.active {
  background: var(--sidebar-active-bg);
}

.sidebar-nav li a.active .nav-title {
  font-weight: 800;
  color: #000000;
}

:root[data-theme="dark"] .sidebar-nav li a.active .nav-title {
  color: #ffffff;
}

.menu-toggle {
  display: flex;
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 220;
  width: 40px;
  height: 40px;
  border: none;
  border-radius: 0;
  background: transparent;
  cursor: pointer;
  align-items: center;
  justify-content: center;
  padding: 0;
}

.menu-toggle .material-symbols-rounded {
  font-size: 24px;
  color: var(--ink-black);
}

.overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: var(--overlay-bg);
  z-index: 50;
}

.overlay.open {
  display: block;
}

.mobile-gnb-gradient {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 116px;
  pointer-events: none;
  z-index: 190;
  background: linear-gradient(
    to top,
    rgba(255, 255, 255, 0) 0%,
    rgba(255, 255, 255, 0.92) 56%,
    rgba(255, 255, 255, 1) 100%
  );
}

:root[data-theme="dark"] .mobile-gnb-gradient {
  background: linear-gradient(
    to top,
    rgba(11, 18, 32, 0) 0%,
    rgba(11, 18, 32, 0.92) 56%,
    rgba(11, 18, 32, 1) 100%
  );
}

.top-controls {
  position: fixed;
  top: 12px;
  right: 16px;
  z-index: 220;
  display: flex;
  align-items: center;
  gap: 8px;
}

.theme-mode-toggle {
  display: flex;
  border: 1px solid var(--control-border);
  background: var(--control-bg);
}

.theme-btn {
  border: 0;
  background: transparent;
  color: var(--control-text);
  font-family: "Google Sans Flex", var(--font-ui);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.8px;
  text-transform: uppercase;
  cursor: pointer;
  padding: 9px 11px;
  min-width: 42px;
}

.theme-btn.active {
  background: var(--control-active-bg);
  color: var(--control-active-text);
}

.main {
  flex: 1;
  margin-left: 0;
}

.article-container {
  max-width: 760px;
  margin: 0 auto;
  padding: 80px 24px 80px;
}

.meta {
  margin-bottom: 26px;
}

.meta-kicker {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 800;
  color: var(--ink-black);
  letter-spacing: 1px;
  text-transform: uppercase;
  line-height: 1.33;
  margin-bottom: 10px;
}

.meta-author {
  font-family: var(--font-ui);
  font-size: 17px;
  font-weight: 800;
  color: var(--ink-black);
  letter-spacing: 0;
  line-height: 1.2;
}

.meta-date {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  color: var(--meta-date-color);
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-top: 6px;
}

h1 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 2.3rem;
  line-height: 1.24;
  letter-spacing: -0.5px;
  color: var(--page-ink);
  margin-bottom: 32px;
}

h2 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.35rem;
  line-height: 1.24;
  letter-spacing: -0.28px;
  color: var(--page-ink);
  margin-top: 40px;
  margin-bottom: 16px;
}

p {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.64;
  color: var(--page-ink);
  letter-spacing: 0.09px;
  margin-bottom: 1.25rem;
}

ul {
  list-style: none;
  padding: 0;
  margin-bottom: 1.25rem;
}

ul li {
  padding-left: 16px;
  margin-bottom: 16px;
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.62;
  border-left: 2px solid var(--border-strong);
  padding-top: 4px;
  padding-bottom: 4px;
}

ul li strong {
  font-weight: 700;
  color: var(--ink-black);
}

.section-break {
  width: 100%;
  height: 1px;
  background: var(--hairline);
  margin: 40px 0;
  border: none;
}

.author-footer {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 2px solid var(--border-strong);
}

.author-footer .name {
  font-family: var(--font-ui);
  font-weight: 700;
  font-size: 14px;
  color: var(--ink-black);
  letter-spacing: 0.3px;
}

.author-footer .role {
  font-family: var(--font-mono);
}

.author-signature {
  margin-top: 48px;
  text-align: right;
}

.signature-img {
  width: 180px;
  height: auto;
}
  font-size: 11px;
  color: var(--caption-gray);
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-top: 4px;
}

@media (max-width: 960px) {
  :root { --sidebar-width: 280px; }
}

@media (max-width: 499px) {
  .sidebar.open {
    width: 100vw;
    min-width: 100vw;
  }

  .article-container {
    padding-top: 80px;
  }

  .top-controls {
    right: 12px;
  }
}

@media (max-width: 680px) {
  html { font-size: 16px; }

  .theme-btn {
    font-size: 11px;
    min-width: 36px;
    padding: 8px 9px;
  }

  .article-container {
    padding: 72px 20px 48px;
  }

  h1 {
    font-size: 2rem;
    line-height: 1.12;
  }

  h2 {
    font-size: 1.2rem;
  }
}