/* ========================================
   Technical Guidance Memo Library — Styles
   ======================================== */

/* --- Reset & Base --- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --color-bg: #f8f9fa;
  --color-surface: #ffffff;
  --color-text: #1a1a2e;
  --color-text-secondary: #555770;
  --color-primary: #1b3a5c;
  --color-primary-light: #2a5a8c;
  --color-accent: #c8553d;
  --color-border: #d4d6db;
  --color-border-light: #e8eaed;
  --color-status-active: #1a7742;
  --color-status-active-bg: #e6f4ed;
  --color-status-draft: #8a6d00;
  --color-status-draft-bg: #fef7e0;
  --color-status-superseded: #7a7a8a;
  --color-status-superseded-bg: #f0f0f4;
  --color-status-archived: #6b6b7b;
  --color-status-archived-bg: #eaeaef;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 2px 8px rgba(0, 0, 0, 0.1);
  --radius: 6px;
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    sans-serif;
  --font-mono: "IBM Plex Mono", "Fira Code", monospace;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: var(--color-primary-light);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

/* --- Container --- */
.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* --- Header --- */
.site-header {
  background: var(--color-primary);
  color: #fff;
  padding: 1rem 0;
  border-bottom: 3px solid var(--color-accent);
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.site-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: #fff;
  text-decoration: none;
}

.site-logo:hover {
  text-decoration: none;
  opacity: 0.95;
}

.logo-icon {
  font-size: 1.75rem;
  color: var(--color-accent);
}

.logo-text {
  display: flex;
  flex-direction: column;
}

.logo-title {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  line-height: 1.2;
}

.logo-subtitle {
  font-size: 0.75rem;
  opacity: 0.7;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.site-nav {
  display: flex;
  gap: 1.5rem;
}

.site-nav a {
  color: rgba(255, 255, 255, 0.85);
  font-size: 0.9rem;
  font-weight: 500;
}

.site-nav a:hover {
  color: #fff;
  text-decoration: none;
}

/* --- Main --- */
.site-main {
  flex: 1;
  padding: 2.5rem 0;
}

/* --- Footer --- */
.site-footer {
  background: var(--color-primary);
  color: rgba(255, 255, 255, 0.6);
  text-align: center;
  padding: 1.25rem 0;
  font-size: 0.85rem;
}

/* ========================================
   Home Page
   ======================================== */
.hero {
  text-align: center;
  padding: 2rem 0 2.5rem;
}

.hero h1 {
  font-size: 2rem;
  font-weight: 800;
  color: var(--color-primary);
  margin-bottom: 0.5rem;
}

.hero p {
  font-size: 1.1rem;
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* --- Search --- */
.search-section {
  margin-bottom: 2rem;
}

.search-box {
  position: relative;
}

.search-box input {
  width: 100%;
  padding: 0.85rem 1rem 0.85rem 2.75rem;
  border: 2px solid var(--color-border);
  border-radius: var(--radius);
  font-size: 1rem;
  font-family: var(--font-sans);
  background: var(--color-surface);
  transition: border-color 0.2s;
}

.search-box input:focus {
  outline: none;
  border-color: var(--color-primary-light);
}

.search-box::before {
  content: "\26B2";
  position: absolute;
  left: 1rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--color-text-secondary);
  font-size: 1.1rem;
}

/* --- Filter Tabs --- */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 2rem;
}

.filter-btn {
  padding: 0.4rem 1rem;
  border: 1px solid var(--color-border);
  border-radius: 99px;
  background: var(--color-surface);
  font-size: 0.85rem;
  font-family: var(--font-sans);
  color: var(--color-text-secondary);
  cursor: pointer;
  transition: all 0.15s;
}

.filter-btn:hover {
  border-color: var(--color-primary-light);
  color: var(--color-primary-light);
}

.filter-btn.active {
  background: var(--color-primary);
  color: #fff;
  border-color: var(--color-primary);
}

/* --- Stats Bar --- */
.stats-bar {
  display: flex;
  gap: 2rem;
  justify-content: center;
  margin-bottom: 2.5rem;
}

.stat {
  text-align: center;
}

.stat-value {
  display: block;
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--color-primary);
}

.stat-label {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-secondary);
}

/* ========================================
   Memo Cards (listing)
   ======================================== */
.memo-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.memo-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius);
  padding: 1.25rem 1.5rem;
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.2s, border-color 0.2s;
  display: block;
  color: inherit;
}

.memo-card:hover {
  text-decoration: none;
  box-shadow: var(--shadow-md);
  border-color: var(--color-primary-light);
}

.memo-card-top {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.5rem;
}

.memo-card-number {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-primary);
}

.memo-card-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 0.35rem;
}

.memo-card-summary {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  line-height: 1.5;
  margin-bottom: 0.75rem;
}

.memo-card-footer {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-size: 0.8rem;
  color: var(--color-text-secondary);
}

.memo-card-category {
  background: var(--color-border-light);
  padding: 0.15rem 0.6rem;
  border-radius: 99px;
  font-weight: 500;
}

/* --- Status Badges --- */
.memo-status {
  display: inline-block;
  padding: 0.15rem 0.65rem;
  border-radius: 99px;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.memo-status--active {
  background: var(--color-status-active-bg);
  color: var(--color-status-active);
}

.memo-status--draft {
  background: var(--color-status-draft-bg);
  color: var(--color-status-draft);
}

.memo-status--superseded {
  background: var(--color-status-superseded-bg);
  color: var(--color-status-superseded);
}

.memo-status--archived {
  background: var(--color-status-archived-bg);
  color: var(--color-status-archived);
}

/* --- No Results --- */
.no-results {
  text-align: center;
  padding: 3rem 1rem;
  color: var(--color-text-secondary);
  display: none;
}

.no-results.visible {
  display: block;
}

/* ========================================
   Memo Detail Page
   ======================================== */
.memo-detail {
  max-width: 720px;
  margin: 0 auto;
}

.memo-header {
  margin-bottom: 2rem;
  padding-bottom: 1.5rem;
  border-bottom: 2px solid var(--color-border-light);
}

.memo-meta-bar {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}

.memo-id {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--color-primary);
}

.memo-title {
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--color-text);
  line-height: 1.3;
  margin-bottom: 1rem;
}

.meta-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 0.75rem;
}

.meta-item {
  background: var(--color-bg);
  padding: 0.6rem 0.9rem;
  border-radius: var(--radius);
}

.meta-item dt {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-secondary);
  font-weight: 600;
  margin-bottom: 0.15rem;
}

.meta-item dd {
  font-size: 0.9rem;
  font-weight: 500;
}

/* --- Memo Body --- */
.memo-body {
  line-height: 1.75;
}

.memo-body h2 {
  font-size: 1.35rem;
  font-weight: 700;
  margin-top: 2rem;
  margin-bottom: 0.75rem;
  padding-bottom: 0.35rem;
  border-bottom: 1px solid var(--color-border-light);
  color: var(--color-primary);
}

.memo-body h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-top: 1.5rem;
  margin-bottom: 0.5rem;
}

.memo-body p {
  margin-bottom: 1rem;
}

.memo-body ul,
.memo-body ol {
  margin-bottom: 1rem;
  padding-left: 1.5rem;
}

.memo-body li {
  margin-bottom: 0.35rem;
}

.memo-body blockquote {
  border-left: 3px solid var(--color-accent);
  padding: 0.75rem 1.25rem;
  margin: 1.25rem 0;
  background: var(--color-bg);
  border-radius: 0 var(--radius) var(--radius) 0;
  color: var(--color-text-secondary);
}

.memo-body code {
  font-family: var(--font-mono);
  background: var(--color-bg);
  padding: 0.15rem 0.4rem;
  border-radius: 3px;
  font-size: 0.9em;
}

.memo-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.25rem 0;
  font-size: 0.9rem;
}

.memo-body th,
.memo-body td {
  padding: 0.6rem 0.9rem;
  border: 1px solid var(--color-border);
  text-align: left;
}

.memo-body th {
  background: var(--color-bg);
  font-weight: 600;
}

/* --- Memo Footer --- */
.memo-footer {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-border-light);
}

.back-link {
  font-weight: 500;
  font-size: 0.95rem;
}

/* --- Page Header (listing page) --- */
.page-header {
  margin-bottom: 2rem;
}

.page-header h1 {
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--color-primary);
  margin-bottom: 0.25rem;
}

.page-header p {
  color: var(--color-text-secondary);
}

/* ========================================
   Responsive
   ======================================== */
@media (max-width: 640px) {
  .header-inner {
    flex-direction: column;
    text-align: center;
  }

  .hero h1 {
    font-size: 1.5rem;
  }

  .stats-bar {
    gap: 1rem;
  }

  .stat-value {
    font-size: 1.35rem;
  }

  .memo-title {
    font-size: 1.35rem;
  }

  .meta-grid {
    grid-template-columns: 1fr;
  }

  .memo-card-footer {
    flex-wrap: wrap;
  }
}