/* ============================================================
   ArcSafe Design System — arcsafe.css  v2.0
   Industrial Engineering Field Readability Edition

   Philosophy:
   - Field engineers read on mobile, standing, in poor light
   - This is a technical reference, not a SaaS dashboard
   - Every sizing decision optimized for 35-60 year old engineers
   - Think: industrial manual, not startup product page
   ============================================================ */

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

/* ============================================================
   DESIGN TOKENS
   ============================================================ */
:root {
  --navy:        #0d1f3c;
  --navy-mid:    #1a3360;
  --navy-light:  #253d6b;
  --sky:         #7ab8d4;
  --sky-light:   #b8d9ea;
  --sky-pale:    #e8f4f9;
  --white:       #fafcfd;
  --gray-50:     #f5f7fa;
  --gray-100:    #eaecf0;
  --gray-200:    #d1d5db;
  --gray-400:    #9ba3af;
  --gray-600:    #4b5563;
  --gray-700:    #374151;
  --gray-800:    #1f2937;
  --green:       #16a34a;
  --green-pale:  #f0fdf4;
  --amber:       #b45309;
  --amber-pale:  #fffbeb;
  --red:         #dc2626;

  --font-body:   'Noto Sans KR', sans-serif;
  --font-en:     'DM Sans', sans-serif;
  --font-mono:   'IBM Plex Mono', monospace;

  /* Field-optimized type scale */
  --text-xs:    13px;
  --text-sm:    15px;
  --text-base:  17px;
  --text-md:    18px;
  --text-lg:    20px;
  --text-xl:    24px;
  --text-2xl:   30px;
  --text-3xl:   38px;

  /* Line heights */
  --leading-tight:   1.25;
  --leading-snug:    1.45;
  --leading-normal:  1.7;
  --leading-relaxed: 1.88;

  /* Spacing */
  --space-1:  4px;  --space-2:  8px;  --space-3:  12px;
  --space-4:  16px; --space-5:  20px; --space-6:  24px;
  --space-8:  32px; --space-10: 40px; --space-12: 48px;
  --space-16: 64px;

  /* Layout */
  --nav-height:    68px;
  --sidebar-width: 268px;
  --content-max:   820px;

  /* Radii */
  --radius-sm: 6px; --radius-md: 10px;
  --radius-lg: 14px; --radius-xl: 18px;
}

/* ============================================================
   BASE
   ============================================================ */
html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}
body {
  font-family: var(--font-body);
  font-size: var(--text-md);
  line-height: var(--leading-normal);
  background: var(--white);
  color: var(--navy);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
::-webkit-scrollbar { width: 5px; }
::-webkit-scrollbar-track { background: var(--gray-50); }
::-webkit-scrollbar-thumb { background: var(--sky); border-radius: 3px; }

/* ============================================================
   TOPBAR
   ============================================================ */
.topbar {
  background: var(--navy);
  padding: 9px 5vw;
  display: flex; align-items: center; justify-content: space-between;
}
.topbar-left {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: rgba(255,255,255,0.45);
  letter-spacing: 0.05em;
}
.topbar-left span { color: var(--sky); margin-right: 14px; }
.topbar-lang {
  font-family: var(--font-en); font-size: var(--text-xs); font-weight: 500;
  color: rgba(255,255,255,0.45); text-decoration: none;
  letter-spacing: 0.08em; padding: 4px 8px; border-radius: 4px;
  transition: color 0.15s, background 0.15s;
}
.topbar-lang.active { color: var(--sky-light); }
.topbar-lang:hover  { color: var(--sky-light); background: rgba(255,255,255,0.06); }
.topbar-sep { color: rgba(255,255,255,0.2); font-size: 11px; margin: 0 2px; }

/* ============================================================
   NAV
   ============================================================ */
nav.platform-nav {
  position: sticky; top: 0; z-index: 100;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 5vw; height: var(--nav-height);
  background: rgba(250,252,253,0.96);
  backdrop-filter: blur(24px); -webkit-backdrop-filter: blur(24px);
  border-bottom: 1px solid var(--gray-100);
  box-shadow: 0 1px 0 var(--gray-100);
}
.nav-logo { display: flex; align-items: center; gap: 10px; text-decoration: none; }
.nav-brand {
  font-family: var(--font-en); font-weight: 600; font-size: 20px;
  color: var(--navy); letter-spacing: -0.03em;
}
.nav-brand sup {
  font-size: 10px; font-weight: 400; color: var(--sky);
  letter-spacing: 0.08em; margin-left: 4px; vertical-align: super;
}
.nav-links { display: flex; align-items: center; gap: 2px; list-style: none; }
.nav-links a {
  font-size: var(--text-sm); font-weight: 400; color: var(--gray-600);
  text-decoration: none; padding: 8px 14px;
  border-radius: var(--radius-md);
  transition: color 0.15s, background 0.15s; white-space: nowrap;
}
.nav-links a:hover  { color: var(--navy); background: var(--gray-50); }
.nav-links a.active { color: var(--navy); font-weight: 600; background: var(--sky-pale); }
.nav-right { display: flex; align-items: center; gap: 10px; }
.nav-portal-btn {
  font-family: var(--font-en); font-size: var(--text-sm); font-weight: 600;
  color: var(--white); background: var(--navy);
  padding: 9px 18px; border-radius: var(--radius-md);
  text-decoration: none; transition: background 0.2s; white-space: nowrap;
}
.nav-portal-btn:hover { background: var(--navy-mid); }

/* ============================================================
   PAGE HEADER
   ============================================================ */
.page-header {
  padding: var(--space-12) 5vw var(--space-10);
  border-bottom: 1px solid var(--gray-100); background: var(--white);
}
.breadcrumb {
  display: flex; align-items: center; gap: 8px;
  font-family: var(--font-mono); font-size: var(--text-xs);
  color: var(--gray-400); margin-bottom: var(--space-5); flex-wrap: wrap;
}
.breadcrumb a { color: var(--gray-400); text-decoration: none; transition: color 0.15s; }
.breadcrumb a:hover { color: var(--sky); }
.breadcrumb-sep { color: var(--gray-200); }
.page-eyebrow {
  font-family: var(--font-mono); font-size: var(--text-xs);
  letter-spacing: 0.14em; color: var(--sky);
  text-transform: uppercase; display: block; margin-bottom: var(--space-3);
}
.page-title {
  font-size: clamp(26px, 4vw, 40px); font-weight: 700; color: var(--navy);
  letter-spacing: -0.03em; line-height: var(--leading-tight); margin-bottom: var(--space-4);
}
.page-desc {
  font-size: var(--text-md); font-weight: 300; color: var(--gray-600);
  line-height: var(--leading-relaxed); max-width: 600px;
}

/* ============================================================
   SIDEBAR LAYOUT
   ============================================================ */
.sidebar-layout {
  display: grid; grid-template-columns: var(--sidebar-width) 1fr;
  min-height: calc(100vh - 120px);
}
.sidebar {
  border-right: 1px solid var(--gray-100);
  padding: var(--space-6) 0;
  position: sticky; top: var(--nav-height);
  height: calc(100vh - var(--nav-height));
  overflow-y: auto; background: var(--gray-50);
}
.sidebar::-webkit-scrollbar { width: 3px; }
.sidebar-section { margin-bottom: var(--space-6); }
.sidebar-section-title {
  font-family: var(--font-mono); font-size: var(--text-xs);
  letter-spacing: 0.12em; color: var(--gray-400);
  text-transform: uppercase; padding: 0 20px; margin-bottom: var(--space-2);
}
.sidebar-link {
  display: flex; align-items: center; gap: var(--space-3);
  padding: 11px 20px; font-size: var(--text-sm); font-weight: 400;
  color: var(--gray-600); text-decoration: none;
  border-right: 3px solid transparent;
  transition: color 0.15s, background 0.15s, border-color 0.15s;
  line-height: var(--leading-snug);
}
.sidebar-link:hover { color: var(--navy); background: rgba(122,184,212,0.07); }
.sidebar-link.active {
  color: var(--navy); font-weight: 600;
  background: var(--sky-pale); border-right-color: var(--sky);
}
.sidebar-link .code-tag { font-family: var(--font-mono); font-size: var(--text-xs); color: var(--gray-400); }
.sidebar-link.active .code-tag { color: var(--sky); }
.main-content { padding: var(--space-10) 5vw; max-width: var(--content-max); }

/* ============================================================
   BADGES
   ============================================================ */
.badge {
  display: inline-flex; align-items: center; gap: 5px;
  font-family: var(--font-mono); font-size: var(--text-xs); font-weight: 500;
  letter-spacing: 0.06em; padding: 4px 10px; border-radius: var(--radius-sm);
}
.badge-free { background: var(--green-pale); color: var(--green);  border: 1px solid rgba(22,163,74,0.2); }
.badge-paid { background: var(--amber-pale); color: var(--amber); border: 1px solid rgba(180,83,9,0.2); }
.badge-ex   { background: rgba(220,38,38,0.08);  color: #b91c1c; }
.badge-pip  { background: rgba(37,99,235,0.08);  color: #1d4ed8; }
.badge-msk  { background: rgba(22,163,74,0.08);  color: #15803d; }
.badge-new  { background: rgba(122,184,212,0.15); color: var(--navy-mid); }

/* ============================================================
   CARDS
   ============================================================ */
.card {
  background: var(--white); border: 1px solid var(--gray-100);
  border-radius: var(--radius-lg); padding: var(--space-6) var(--space-8);
  transition: border-color 0.2s, box-shadow 0.2s;
}
.card:hover { border-color: var(--sky); box-shadow: 0 6px 24px rgba(13,31,60,0.07); }
.card a { text-decoration: none; color: inherit; }

/* ============================================================
   MOBILE BOTTOM NAV
   ============================================================ */
.mobile-nav {
  display: none; position: fixed;
  bottom: 0; left: 0; right: 0; z-index: 100;
  background: rgba(250,252,253,0.97);
  backdrop-filter: blur(24px); -webkit-backdrop-filter: blur(24px);
  border-top: 1.5px solid var(--gray-100);
  padding: 6px 0 env(safe-area-inset-bottom, 10px);
}
.mobile-nav-inner { display: flex; justify-content: space-around; }
.mobile-tab {
  display: flex; flex-direction: column; align-items: center; gap: 4px;
  text-decoration: none; padding: 6px 12px; flex: 1;
  min-height: 52px; justify-content: center;
}
.mobile-tab svg { width: 24px; height: 24px; stroke: var(--gray-400); fill: none; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.mobile-tab span { font-size: 11px; color: var(--gray-400); font-weight: 400; }
.mobile-tab.active svg  { stroke: var(--navy); }
.mobile-tab.active span { color: var(--navy); font-weight: 600; }

/* ============================================================
   FOOTER
   ============================================================ */
footer.platform-footer { background: var(--navy); padding: var(--space-12) 5vw var(--space-8); }
.footer-bottom {
  display: flex; justify-content: space-between;
  font-size: var(--text-sm); color: rgba(255,255,255,0.3);
  font-weight: 300; flex-wrap: wrap; gap: var(--space-3);
  padding-top: var(--space-6); border-top: 1px solid rgba(255,255,255,0.08);
}

/* ============================================================
   REVEAL
   ============================================================ */
.reveal { opacity: 0; transform: translateY(16px); transition: opacity 0.5s ease, transform 0.5s ease; }
.reveal.visible { opacity: 1; transform: none; }

/* ============================================================
   DOCUMENT TYPOGRAPHY
   ============================================================ */
.doc-h2 {
  font-size: clamp(20px, 2.5vw, 26px); font-weight: 700; color: var(--navy);
  letter-spacing: -0.02em; line-height: var(--leading-snug);
  margin: var(--space-12) 0 var(--space-5);
  padding-top: var(--space-12);
  border-top: 2px solid var(--gray-100);
  display: flex; align-items: center; gap: var(--space-3);
}
.doc-h2:first-of-type { border-top: none; padding-top: 0; margin-top: 0; }
.doc-h2-num {
  font-family: var(--font-mono); font-size: var(--text-xs);
  border-radius: var(--radius-sm); padding: 3px 9px; flex-shrink: 0;
}
.doc-h3 {
  font-size: clamp(17px, 2vw, 20px); font-weight: 700; color: var(--navy-mid);
  margin: var(--space-8) 0 var(--space-4);
  display: flex; align-items: center; gap: var(--space-3);
  line-height: var(--leading-snug);
}
.doc-h3::before { content: ''; width: 4px; height: 18px; border-radius: 2px; flex-shrink: 0; }

.doc-p {
  font-size: var(--text-md); font-weight: 300; color: var(--gray-800);
  line-height: var(--leading-relaxed); margin-bottom: var(--space-5);
}
.doc-p:last-child { margin-bottom: 0; }
.doc-p strong { font-weight: 700; color: var(--navy); }
.doc-p em     { font-style: normal; font-weight: 600; }
.doc-p a      { color: var(--sky); text-decoration: underline; text-underline-offset: 3px; }

code {
  font-family: var(--font-mono); font-size: 15px;
  background: var(--gray-100); color: var(--navy-mid);
  padding: 3px 8px; border-radius: var(--radius-sm);
  border: 1px solid var(--gray-200);
}

/* ============================================================
   CALLOUT BLOCKS
   ============================================================ */
.callout {
  padding: var(--space-5) var(--space-6);
  border-radius: var(--radius-md); border-left: 4px solid; margin: var(--space-6) 0;
}
.callout-info    { background: var(--sky-pale);          border-color: var(--sky);   }
.callout-danger  { background: rgba(220,38,38,0.05);     border-color: #dc2626;      }
.callout-success { background: var(--green-pale);        border-color: var(--green); }
.callout-warning { background: var(--amber-pale);        border-color: #f59e0b;      }
.callout-ex      { background: rgba(220,38,38,0.04);     border-color: #b91c1c;      }
.callout-code    { background: rgba(37,99,235,0.04);     border-color: #1d4ed8;      }
.callout-label {
  font-family: var(--font-mono); font-size: var(--text-xs);
  letter-spacing: 0.1em; color: var(--gray-400); margin-bottom: var(--space-3); display: block;
}
.callout p { font-size: var(--text-sm); color: var(--gray-800); line-height: var(--leading-relaxed); margin: 0; }
.callout p + p { margin-top: var(--space-3); }
.callout p strong { font-weight: 700; color: var(--navy); }

/* ============================================================
   ENGINEERING TABLES
   ============================================================ */
.tbl-wrap {
  border-radius: var(--radius-lg); overflow: hidden;
  border: 1px solid var(--gray-200); margin: var(--space-6) 0;
  overflow-x: auto; -webkit-overflow-scrolling: touch;
}
.doc-table { width: 100%; border-collapse: collapse; font-size: var(--text-sm); min-width: 500px; }
.doc-table thead th {
  background: var(--navy); color: var(--white); font-weight: 600;
  font-size: var(--text-sm); padding: 14px 18px; text-align: left;
  letter-spacing: 0.01em; white-space: nowrap;
}
.doc-table tbody tr { transition: background 0.1s; }
.doc-table tbody tr:nth-child(even) { background: var(--gray-50); }
.doc-table tbody tr:hover { background: var(--sky-pale); }
.doc-table tbody td {
  padding: 13px 18px; border-bottom: 1px solid var(--gray-100);
  font-weight: 300; color: var(--gray-800);
  vertical-align: top; line-height: var(--leading-normal); font-size: var(--text-sm);
}
.doc-table tbody tr:last-child td { border-bottom: none; }
.doc-table tbody td:first-child {
  font-family: var(--font-mono); font-size: 14px; font-weight: 600; color: var(--navy-mid);
}

/* ============================================================
   CRITERION BLOCKS
   ============================================================ */
.criterion-block { margin: var(--space-5) 0; border: 1px solid var(--gray-200); border-radius: var(--radius-lg); overflow: hidden; }
.criterion-header {
  display: flex; align-items: center; gap: var(--space-3);
  background: var(--gray-50); padding: 14px 18px; border-bottom: 1px solid var(--gray-200);
}
.criterion-topic { font-family: var(--font-mono); font-size: 14px; font-weight: 600; color: var(--navy-mid); flex: 1; }
.criterion-cat   { font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.06em; padding: 3px 8px; border-radius: 4px; }
.criterion-row {
  display: grid; grid-template-columns: 210px 90px 1fr;
  border-bottom: 1px solid var(--gray-100); align-items: stretch;
}
.criterion-row:last-child { border-bottom: none; }
.cr-condition {
  padding: 14px 18px; font-family: var(--font-mono); font-size: 14px;
  color: var(--navy-mid); font-weight: 600;
  border-right: 1px solid var(--gray-100); background: var(--white);
  display: flex; align-items: center;
}
.cr-level {
  padding: 14px 12px; font-family: var(--font-mono); font-size: 13px; font-weight: 700;
  border-right: 1px solid var(--gray-100);
  display: flex; align-items: center; justify-content: center; text-align: center;
}
.cr-level-high, .cr-high     { background: rgba(220,38,38,0.07);  color: #b91c1c; }
.cr-level-medium, .cr-medium { background: rgba(245,158,11,0.07); color: #b45309; }
.cr-level-ok, .cr-ok         { background: rgba(22,163,74,0.07);  color: #15803d; }
.cr-action {
  padding: 14px 18px; font-size: var(--text-sm); font-weight: 300;
  color: var(--gray-700); line-height: var(--leading-normal); display: flex; align-items: center;
}

/* ============================================================
   CHECKLIST
   ============================================================ */
.checklist-grid { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-3); margin: var(--space-5) 0; }
.checklist-item {
  display: flex; align-items: flex-start; gap: var(--space-3);
  padding: 14px 16px; background: var(--gray-50);
  border: 1px solid var(--gray-100); border-radius: var(--radius-md); min-height: 52px;
}
.check-box { width: 20px; height: 20px; border: 2px solid var(--gray-300); border-radius: 5px; flex-shrink: 0; margin-top: 1px; }
.check-text { font-size: var(--text-sm); font-weight: 300; color: var(--gray-700); line-height: var(--leading-normal); }
.check-text strong { font-weight: 700; color: var(--navy); }

.checklist { background: var(--navy); border-radius: var(--radius-lg); padding: var(--space-8); margin: var(--space-6) 0; }
.checklist-title { font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.12em; color: var(--sky); margin-bottom: var(--space-5); }
.checklist .checklist-item { background: rgba(255,255,255,0.04); border-color: rgba(255,255,255,0.08); }
.checklist .check-box { border-color: rgba(255,255,255,0.3); }
.checklist .check-text { color: rgba(255,255,255,0.75); }

/* ============================================================
   STORY FLOW
   ============================================================ */
.story-flow { display: flex; flex-direction: column; gap: 0; margin: var(--space-6) 0; border: 1px solid var(--gray-200); border-radius: var(--radius-lg); overflow: hidden; }
.story-step { display: grid; grid-template-columns: 88px 1fr; border-bottom: 1px solid var(--gray-100); }
.story-step:last-child { border-bottom: none; }
.story-step-label {
  background: var(--gray-50); padding: 18px 12px; border-right: 1px solid var(--gray-100);
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 8px;
}
.ssl-icon { width: 36px; height: 36px; border-radius: var(--radius-md); display: flex; align-items: center; justify-content: center; }
.ssl-icon svg { width: 18px; height: 18px; fill: none; stroke-width: 1.8; stroke-linecap: round; }
.ssl-word { font-family: var(--font-mono); font-size: 10px; letter-spacing: 0.06em; color: var(--gray-400); text-align: center; }
.story-step-content { padding: 18px 22px; }
.ssc-title { font-size: var(--text-md); font-weight: 700; color: var(--navy); margin-bottom: 8px; line-height: var(--leading-snug); }
.ssc-desc  { font-size: var(--text-sm); font-weight: 300; color: var(--gray-600); line-height: var(--leading-relaxed); }

/* ============================================================
   TOC + DOC RIGHT PANEL
   ============================================================ */
.doc-right-panel {
  border-left: 1px solid var(--gray-100); padding: var(--space-6) var(--space-5);
  position: sticky; top: var(--nav-height);
  height: calc(100vh - var(--nav-height)); overflow-y: auto;
}
.doc-right-panel::-webkit-scrollbar { width: 3px; }
.toc-title { font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.1em; color: var(--gray-400); margin-bottom: var(--space-3); text-transform: uppercase; }
.toc-link {
  display: block; font-size: 14px; font-weight: 400; color: var(--gray-400);
  text-decoration: none; padding: 7px 0 7px 12px;
  border-left: 2px solid var(--gray-100); margin-bottom: 2px;
  line-height: var(--leading-snug); transition: color 0.15s, border-color 0.15s;
}
.toc-link:hover  { color: var(--navy); border-left-color: var(--sky); }
.toc-link.active { color: var(--navy); border-left-color: var(--sky); font-weight: 600; }

.hub-panel { margin-top: var(--space-6); padding-top: var(--space-5); border-top: 1px solid var(--gray-100); }
.hub-link {
  display: flex; align-items: center; gap: 8px;
  padding: 11px 12px; border: 1px solid var(--gray-100);
  border-radius: var(--radius-md); text-decoration: none;
  color: var(--gray-600); font-size: 14px; margin-bottom: 8px;
  transition: all 0.15s; line-height: var(--leading-snug);
}
.hub-link:hover { border-color: var(--sky); color: var(--navy); background: var(--sky-pale); }
.hub-link svg { width: 15px; height: 15px; stroke: var(--sky); fill: none; stroke-width: 2; stroke-linecap: round; flex-shrink: 0; }

/* ============================================================
   DOCUMENT SIDEBAR
   ============================================================ */
.doc-sidebar, .case-sidebar, .codes-sidebar {
  border-right: 1px solid var(--gray-100); background: var(--gray-50);
  padding: var(--space-6) 0;
  position: sticky; top: var(--nav-height);
  height: calc(100vh - var(--nav-height)); overflow-y: auto;
}
.doc-sidebar::-webkit-scrollbar, .case-sidebar::-webkit-scrollbar, .codes-sidebar::-webkit-scrollbar { width: 3px; }

.sidebar-back, .csb-back {
  display: flex; align-items: center; gap: 8px;
  padding: 0 18px var(--space-5); border-bottom: 1px solid var(--gray-100);
  margin-bottom: var(--space-5); font-size: var(--text-sm);
  color: var(--gray-400); text-decoration: none; transition: color 0.15s;
}
.sidebar-back:hover, .csb-back:hover { color: var(--sky); }
.sidebar-back svg, .csb-back svg { width: 14px; height: 14px; stroke: currentColor; fill: none; stroke-width: 2; stroke-linecap: round; }

.sidebar-cat-label, .csb-label {
  font-family: var(--font-mono); font-size: var(--text-xs);
  letter-spacing: 0.12em; color: var(--gray-400);
  padding: 0 18px var(--space-2); display: block; text-transform: uppercase;
}

.sidebar-doc-link, .csb-link {
  display: flex; flex-direction: column; gap: 3px;
  padding: 11px 18px; font-size: var(--text-sm); font-weight: 400;
  color: var(--gray-600); text-decoration: none;
  border-right: 3px solid transparent; transition: all 0.15s;
  line-height: var(--leading-snug);
}
.sidebar-doc-link:hover, .csb-link:hover { color: var(--navy); background: rgba(122,184,212,0.07); }
.sidebar-doc-link.active, .csb-link.active { color: var(--navy); font-weight: 600; background: var(--sky-pale); border-right-color: var(--sky); }
.sdl-id, .csb-id { font-family: var(--font-mono); font-size: var(--text-xs); color: var(--gray-400); }
.sidebar-doc-link.active .sdl-id, .csb-link.active .csb-id { color: var(--sky); }

/* ============================================================
   DOCUMENT HEADER
   ============================================================ */
.doc-header { padding-bottom: var(--space-8); border-bottom: 1px solid var(--gray-100); }
.doc-breadcrumb {
  display: flex; align-items: center; gap: 8px;
  font-family: var(--font-mono); font-size: var(--text-xs);
  color: var(--gray-400); margin-bottom: var(--space-5); flex-wrap: wrap;
}
.doc-breadcrumb a { color: var(--gray-400); text-decoration: none; }
.doc-breadcrumb a:hover { color: var(--sky); }
.doc-breadcrumb-sep { color: var(--gray-200); }
.doc-meta-row { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; margin-bottom: var(--space-4); }
.doc-code-id { font-family: var(--font-mono); font-size: 14px; font-weight: 600; border-radius: var(--radius-sm); padding: 4px 12px; border: 1px solid; }
.doc-cat-badge, .doc-status-badge { font-family: var(--font-mono); font-size: var(--text-xs); border-radius: 4px; padding: 4px 10px; border: 1px solid; }
.status-field-verified { background: rgba(22,163,74,0.08); color: #15803d; border-color: rgba(22,163,74,0.2); }
.status-validated      { background: rgba(37,99,235,0.08); color: #1d4ed8; border-color: rgba(37,99,235,0.2); }
.status-draft          { background: var(--gray-100); color: var(--gray-600); border-color: var(--gray-200); }
.doc-version { font-family: var(--font-mono); font-size: var(--text-xs); color: var(--gray-400); }
.doc-date    { font-family: var(--font-mono); font-size: var(--text-xs); color: var(--gray-400); margin-left: auto; }
.doc-title   { font-size: clamp(26px, 4vw, 40px); font-weight: 700; color: var(--navy); letter-spacing: -0.03em; line-height: var(--leading-tight); margin-bottom: var(--space-3); }
.doc-subtitle{ font-size: var(--text-md); font-weight: 300; color: var(--gray-600); line-height: var(--leading-relaxed); margin-bottom: var(--space-6); }
.doc-actions { display: flex; gap: 10px; flex-wrap: wrap; }
.doc-btn {
  display: inline-flex; align-items: center; gap: 7px;
  font-size: var(--text-sm); font-weight: 500;
  padding: 11px 20px; border-radius: var(--radius-md);
  text-decoration: none; border: 1px solid var(--gray-200);
  color: var(--navy); background: var(--white); transition: all 0.15s; white-space: nowrap;
}
.doc-btn:hover { border-color: var(--sky); background: var(--sky-pale); }
.doc-btn svg { width: 15px; height: 15px; stroke: currentColor; fill: none; stroke-width: 2; stroke-linecap: round; }
.doc-btn-primary { background: var(--navy); color: var(--white); border-color: var(--navy); }
.doc-btn-primary:hover { background: var(--navy-mid); border-color: var(--navy-mid); }

/* ============================================================
   HUB CONNECTIONS
   ============================================================ */
.hub-connections { margin-top: var(--space-16); padding: var(--space-8); border-radius: var(--radius-xl); }
.hub-title { font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.1em; margin-bottom: var(--space-5); }
.hub-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-3); }
.hub-item { background: var(--white); border-radius: var(--radius-md); padding: 16px 18px; text-decoration: none; color: inherit; transition: border-color 0.15s, box-shadow 0.15s; display: flex; flex-direction: column; gap: 6px; border: 1px solid; }
.hub-item-type  { font-family: var(--font-mono); font-size: 10px; letter-spacing: 0.1em; color: var(--gray-400); }
.hub-item-id    { font-family: var(--font-mono); font-size: 14px; font-weight: 600; color: var(--navy-mid); }
.hub-item-title { font-size: var(--text-sm); font-weight: 300; color: var(--gray-600); line-height: var(--leading-normal); }

/* ============================================================
   CASE META
   ============================================================ */
.rp-meta, .rp-meta-block { margin-top: var(--space-6); padding-top: var(--space-5); border-top: 1px solid var(--gray-100); }
.rp-meta-row { padding: 10px 0; border-bottom: 1px solid var(--gray-100); }
.rp-meta-row:last-child { border-bottom: none; }
.rp-meta-label { font-family: var(--font-mono); font-size: 11px; color: var(--gray-400); margin-bottom: 3px; display: block; }
.rp-meta-value { font-size: 14px; font-weight: 600; color: var(--navy); }
.rp-link-block { margin-top: var(--space-5); padding-top: var(--space-4); border-top: 1px solid var(--gray-100); }
.rp-hub-link {
  display: flex; align-items: center; gap: 8px;
  padding: 11px 12px; border: 1px solid var(--gray-100); border-radius: var(--radius-md);
  text-decoration: none; color: var(--gray-600); font-size: 14px;
  margin-bottom: 8px; transition: all 0.15s; line-height: var(--leading-snug);
}
.rp-hub-link:hover { border-color: var(--sky); color: var(--navy); background: var(--sky-pale); }
.rp-hub-link svg { width: 15px; height: 15px; stroke: var(--sky); fill: none; stroke-width: 2; stroke-linecap: round; flex-shrink: 0; }

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 1100px) {
  :root { --sidebar-width: 240px; }
}

@media (max-width: 768px) {
  :root {
    --text-md: 17px;
    --text-sm: 15px;
    --nav-height: 60px;
  }
  nav.platform-nav .nav-links     { display: none; }
  nav.platform-nav .nav-portal-btn{ display: none; }
  .mobile-nav { display: block; }
  .topbar     { display: none; }
  body { padding-bottom: calc(72px + env(safe-area-inset-bottom, 0px)); }
  .sidebar-layout   { grid-template-columns: 1fr; }
  .sidebar          { display: none; }
  .doc-sidebar      { display: none; }
  .case-sidebar     { display: none; }
  .codes-sidebar    { display: none; }
  .doc-right-panel  { display: none; }
  .main-content     { padding: var(--space-6) 5vw; }
  .checklist-grid   { grid-template-columns: 1fr; }
  .hub-grid         { grid-template-columns: 1fr; }
  .criterion-row    { grid-template-columns: 1fr; }
  .cr-condition, .cr-level { border-right: none; border-bottom: 1px solid var(--gray-100); }
  .cr-level         { justify-content: flex-start; padding-left: 18px; }
  .tbl-wrap         { border-radius: var(--radius-md); }
  .doc-table        { min-width: 480px; }
  .story-step       { grid-template-columns: 72px 1fr; }
  .doc-btn          { padding: 13px 20px; min-height: 48px; }
}

@media (max-width: 480px) {
  .doc-title, .case-title { font-size: 24px !important; }
  .doc-table { min-width: 420px; }
}

/* ============================================================
   v2.1 READABILITY IMPROVEMENTS
   판단 속도 최적화 — 2025.05
   ============================================================ */

/* ----------------------------------------------------------
   1. 본문 최대 너비 제한 — 72ch
   Wide screen에서 줄 길이 과도 방지
   ---------------------------------------------------------- */
.doc-content,
.doc-body .doc-content,
.case-body .story-section {
  max-width: 72ch;
}

/* Code/Case 본문 전체 영역 */
.doc-body   { padding: 48px 52px 96px; max-width: 860px; }
.case-body  { padding: 40px 44px 96px; }

/* 본문 단락 — 최적 읽기 폭 */
.doc-p,
.doc-content p {
  max-width: 72ch;
}

/* ----------------------------------------------------------
   2. Line-height 강화 — 1.75 이상
   기술 문서 장시간 읽기 피로 감소
   ---------------------------------------------------------- */
:root {
  --leading-relaxed: 1.88;   /* 본문 */
  --leading-normal:  1.75;   /* 테이블, 리스트 */
}

.doc-p,
.doc-content p   { line-height: 1.88; }
.ssc-desc        { line-height: 1.78; }
.callout p       { line-height: 1.78; }
.cr-action       { line-height: 1.75; }
.check-text      { line-height: 1.75; }
.doc-table tbody td { line-height: 1.75; }
.hub-item-title  { line-height: 1.75; }
.cause-text      { line-height: 1.78; }

/* ----------------------------------------------------------
   3. 표 Sticky First Column
   Wide table 모바일 스크롤 시 첫 컬럼 고정
   ---------------------------------------------------------- */
.tbl-sticky {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}
.tbl-sticky .doc-table thead th:first-child,
.tbl-sticky .doc-table tbody td:first-child {
  position: sticky;
  left: 0;
  z-index: 2;
  box-shadow: 2px 0 8px rgba(13,31,60,0.08);
}
.tbl-sticky .doc-table thead th:first-child {
  background: var(--navy);   /* 헤더 배경 유지 */
  z-index: 3;
}
.tbl-sticky .doc-table tbody td:first-child {
  background: var(--white);
}
.tbl-sticky .doc-table tbody tr:nth-child(even) td:first-child {
  background: var(--gray-50);
}
.tbl-sticky .doc-table tbody tr:hover td:first-child {
  background: var(--sky-pale);
}

/* ----------------------------------------------------------
   4. Reading Progress Bar
   문서 상단 thin progress indicator
   ---------------------------------------------------------- */
.reading-progress {
  position: fixed;
  top: 0; left: 0;
  width: 0%;
  height: 3px;
  background: linear-gradient(90deg, var(--sky) 0%, var(--sky-light) 100%);
  z-index: 9999;
  transition: width 0.1s linear;
  border-radius: 0 2px 2px 0;
}

/* ----------------------------------------------------------
   5. 추가 가독성 개선
   ---------------------------------------------------------- */

/* 섹션 구분선 강화 */
.doc-h2 {
  padding-bottom: var(--space-4);
}

/* 체크리스트 hover 상태 */
.checklist-item:hover {
  border-color: var(--sky);
  background: var(--sky-pale);
  cursor: pointer;
}
.checklist .checklist-item:hover {
  background: rgba(255,255,255,0.08);
  border-color: rgba(122,184,212,0.3);
}
/* 체크박스 클릭 시 체크 표시 */
.checklist-item.checked .check-box {
  background: var(--sky);
  border-color: var(--sky);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3E%3Cpolyline points='3 8 6.5 11.5 13 5' stroke='white' stroke-width='2' fill='none' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: center;
  background-size: 12px;
}
.checklist-item.checked .check-text {
  color: var(--gray-400);
  text-decoration: line-through;
  text-decoration-color: var(--gray-300);
}
.checklist .checklist-item.checked .check-text {
  color: rgba(255,255,255,0.4);
}

/* 판단 기준 행 hover */
.criterion-row:hover .cr-action {
  color: var(--navy);
}
.criterion-row:hover {
  background: rgba(122,184,212,0.04);
}

/* 모바일 추가 최적화 */
@media (max-width: 768px) {
  .doc-body  { padding: 24px 5vw 80px; }
  .case-body { padding: 24px 5vw 80px; }
  .doc-p, .doc-content p { max-width: 100%; }
  .doc-content, .story-section { max-width: 100%; }
}

/* ============================================================
   v2.2 COMPONENT SYSTEM
   Reusable engineering document patterns
   ArcSafe Platform — 2025.05
   ============================================================ */

/* ----------------------------------------------------------
   DECISION CARD
   Input condition → Output judgment
   핵심 판단 로직을 카드 형태로 시각화
   ---------------------------------------------------------- */
.decision-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--space-3);
  margin: var(--space-6) 0;
}
.decision-card {
  border-radius: var(--radius-lg);
  border: 1px solid var(--gray-200);
  overflow: hidden;
  background: var(--white);
  transition: box-shadow 0.2s, transform 0.2s;
}
.decision-card:hover {
  box-shadow: 0 6px 24px rgba(13,31,60,0.09);
  transform: translateY(-1px);
}
.dc-condition {
  padding: 14px 18px;
  background: var(--gray-50);
  border-bottom: 1px solid var(--gray-100);
}
.dc-condition-label {
  font-family: var(--font-mono);
  font-size: 11px; letter-spacing: 0.1em;
  color: var(--gray-400); margin-bottom: 6px; display: block;
}
.dc-condition-text {
  font-size: 15px; font-weight: 500;
  color: var(--navy); line-height: 1.5;
}
.dc-result {
  padding: 14px 18px;
  display: flex; align-items: center; gap: 12px;
}
.dc-result-zone {
  font-family: var(--font-mono);
  font-size: 18px; font-weight: 700;
  flex-shrink: 0; min-width: 64px;
}
.dc-result-desc {
  font-size: 14px; font-weight: 300;
  color: var(--gray-600); line-height: 1.65;
}
/* Zone result colors */
.dc-zone-0  { color: #b91c1c; }
.dc-zone-1  { color: #b45309; }
.dc-zone-2  { color: #15803d; }
.dc-zone-np { color: var(--gray-400); }

.dc-zone-0-card { border-top: 3px solid #dc2626; }
.dc-zone-1-card { border-top: 3px solid #f59e0b; }
.dc-zone-2-card { border-top: 3px solid #16a34a; }
.dc-zone-np-card { border-top: 3px solid var(--gray-300); }

/* ----------------------------------------------------------
   FLOW DIAGRAM (text-based)
   판단 흐름도 — Release Grade → Zone
   ---------------------------------------------------------- */
.flow-diagram {
  margin: var(--space-6) 0;
  background: var(--navy);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  overflow-x: auto;
}
.flow-title {
  font-family: var(--font-mono);
  font-size: 11px; letter-spacing: 0.12em;
  color: var(--sky); margin-bottom: var(--space-6);
}
.flow-row {
  display: flex;
  align-items: stretch;
  gap: 0;
  margin-bottom: 10px;
}
.flow-row:last-child { margin-bottom: 0; }
.flow-node {
  flex: 1;
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: var(--radius-md);
  padding: 12px 16px;
  display: flex; flex-direction: column;
  justify-content: center;
}
.flow-node-label {
  font-family: var(--font-mono);
  font-size: 10px; letter-spacing: 0.1em;
  color: rgba(255,255,255,0.4); margin-bottom: 4px;
}
.flow-node-value {
  font-size: 14px; font-weight: 600;
  color: var(--white); line-height: 1.4;
}
.flow-arrow {
  display: flex; align-items: center;
  padding: 0 10px; color: rgba(255,255,255,0.25);
  font-size: 18px; font-family: var(--font-mono);
  flex-shrink: 0;
}
.flow-result {
  background: rgba(122,184,212,0.12);
  border-color: rgba(122,184,212,0.3);
}
.flow-result .flow-node-value { color: var(--sky-light); }
.flow-result-0 { background: rgba(220,38,38,0.15); border-color: rgba(220,38,38,0.3); }
.flow-result-0 .flow-node-value { color: #fca5a5; }
.flow-result-1 { background: rgba(245,158,11,0.15); border-color: rgba(245,158,11,0.3); }
.flow-result-1 .flow-node-value { color: #fcd34d; }
.flow-result-2 { background: rgba(22,163,74,0.15); border-color: rgba(22,163,74,0.3); }
.flow-result-2 .flow-node-value { color: #86efac; }

/* ----------------------------------------------------------
   FIELD NOTE
   현장 실무 메모 — 기준 외 실무 판단 보조
   ---------------------------------------------------------- */
.field-note {
  display: flex; gap: var(--space-4);
  padding: var(--space-5) var(--space-5);
  background: rgba(122,184,212,0.06);
  border: 1px solid rgba(122,184,212,0.2);
  border-radius: var(--radius-md);
  margin: var(--space-5) 0;
}
.field-note-icon {
  width: 36px; height: 36px; border-radius: var(--radius-md);
  background: var(--sky-pale);
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0; margin-top: 1px;
}
.field-note-icon svg {
  width: 18px; height: 18px; stroke: var(--navy-mid);
  fill: none; stroke-width: 1.8; stroke-linecap: round;
}
.field-note-body {}
.field-note-label {
  font-family: var(--font-mono);
  font-size: 11px; letter-spacing: 0.1em;
  color: var(--sky); margin-bottom: 6px; display: block;
}
.field-note-text {
  font-size: 15px; font-weight: 300;
  color: var(--gray-700); line-height: 1.78;
}
.field-note-text strong { font-weight: 700; color: var(--navy); }

/* ----------------------------------------------------------
   COMMON MISJUDGMENT
   현장 오판 패턴 — 일관된 컴포넌트
   ---------------------------------------------------------- */
.misjudgment-list { display: flex; flex-direction: column; gap: var(--space-3); margin: var(--space-5) 0; }
.misjudgment-card {
  border: 1px solid var(--gray-100);
  border-radius: var(--radius-lg); overflow: hidden;
}
.mj-header {
  padding: 12px 18px;
  display: flex; align-items: center; gap: 10px;
  background: rgba(220,38,38,0.04);
  border-bottom: 1px solid rgba(220,38,38,0.08);
}
.mj-tag {
  font-family: var(--font-mono); font-size: 10px;
  letter-spacing: 0.1em; color: #b91c1c;
  background: rgba(220,38,38,0.1); border-radius: 3px; padding: 2px 7px;
  flex-shrink: 0;
}
.mj-wrong {
  font-size: 15px; font-weight: 600;
  color: #b91c1c; font-style: italic;
  line-height: 1.4;
}
.mj-body { padding: 14px 18px; }
.mj-correct-label {
  font-family: var(--font-mono); font-size: 10px;
  letter-spacing: 0.1em; color: #15803d; margin-bottom: 7px; display: block;
}
.mj-correct-text {
  font-size: 15px; font-weight: 300;
  color: var(--gray-700); line-height: 1.78;
}
.mj-correct-text strong { font-weight: 700; color: var(--navy); }

/* ----------------------------------------------------------
   ZONE BADGE (standalone)
   ---------------------------------------------------------- */
.zone-badge {
  display: inline-flex; align-items: center; gap: 6px;
  font-family: var(--font-mono);
  font-size: 13px; font-weight: 700;
  padding: 5px 12px; border-radius: var(--radius-sm);
  border: 1px solid;
}
.zone-badge-0  { background: rgba(220,38,38,0.08);  color: #b91c1c; border-color: rgba(220,38,38,0.2);  }
.zone-badge-1  { background: rgba(245,158,11,0.08); color: #b45309; border-color: rgba(245,158,11,0.2); }
.zone-badge-2  { background: rgba(22,163,74,0.08);  color: #15803d; border-color: rgba(22,163,74,0.2);  }
.zone-badge-np { background: var(--gray-100);       color: var(--gray-600); border-color: var(--gray-200); }

/* ----------------------------------------------------------
   VENTILATION GRADE INDICATOR
   ---------------------------------------------------------- */
.vent-grade-row {
  display: grid; grid-template-columns: repeat(3, 1fr);
  gap: var(--space-3); margin: var(--space-5) 0;
}
.vent-grade-card {
  border-radius: var(--radius-md);
  padding: 16px 18px;
  border: 1px solid;
}
.vg-good    { background: var(--green-pale);          border-color: rgba(22,163,74,0.2); }
.vg-fair    { background: var(--amber-pale);          border-color: rgba(180,83,9,0.2);  }
.vg-poor    { background: rgba(220,38,38,0.05);       border-color: rgba(220,38,38,0.15); }
.vg-title   { font-family: var(--font-mono); font-size: 12px; font-weight: 700; margin-bottom: 8px; }
.vg-good .vg-title  { color: var(--green); }
.vg-fair .vg-title  { color: var(--amber); }
.vg-poor .vg-title  { color: #b91c1c; }
.vg-desc    { font-size: 14px; font-weight: 300; color: var(--gray-700); line-height: 1.65; }
.vg-effect  { margin-top: 8px; font-family: var(--font-mono); font-size: 12px; font-weight: 600; }
.vg-good .vg-effect  { color: var(--green); }
.vg-fair .vg-effect  { color: var(--amber); }
.vg-poor .vg-effect  { color: #b91c1c; }

@media (max-width: 768px) {
  .decision-grid    { grid-template-columns: 1fr; }
  .flow-diagram     { padding: var(--space-5); }
  .flow-row         { flex-direction: column; gap: var(--space-2); }
  .flow-arrow       { transform: rotate(90deg); align-self: center; padding: 4px 0; }
  .vent-grade-row   { grid-template-columns: 1fr; }
}

/* ============================================================
   SEARCH BUTTON — Nav & Global
   ============================================================ */
.nav-search-btn {
  display: flex; align-items: center; gap: 8px;
  height: 36px; padding: 0 14px;
  background: var(--gray-50);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-md);
  font-family: var(--font-body);
  font-size: 14px;
  color: var(--gray-400);
  cursor: pointer;
  text-decoration: none;
  transition: all 0.15s;
  white-space: nowrap;
}
.nav-search-btn:hover {
  border-color: var(--sky);
  background: var(--sky-pale);
  color: var(--navy);
}
.nav-search-btn svg {
  width: 15px; height: 15px;
  stroke: currentColor; fill: none;
  stroke-width: 2; stroke-linecap: round;
  flex-shrink: 0;
}
.nav-search-kbd {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--gray-300);
  margin-left: 4px;
}
/* Mobile: icon only */
.nav-search-text { }
@media (max-width: 900px) {
  .nav-search-btn { padding: 0 10px; }
  .nav-search-text { display: none; }
  .nav-search-kbd  { display: none; }
}