/* ============================================================
   CSS VARIABLES
   ============================================================ */
:root {
  --color-blue: #4065A9;
  --color-blue-light: #C3C9E9;
  --color-blue-bg: rgba(195, 201, 233, 0.2);
  --color-red: #A8404C;
  --color-peach: #FFBE86;
  --color-peach-bg: rgba(255, 190, 134, 0.15);
  --color-green: #417B5A;
  --color-green-bg: rgba(65, 123, 90, 0.1);
  --sidebar-width: 260px;
  --header-height: 60px;
  --font-stack: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --text-color: #333;
  --text-muted: #666;
  --bg-page: #f0f2f8;
  --bg-white: #ffffff;
  --border-radius: 6px;
  --shadow: 0 2px 8px rgba(0,0,0,0.08);
}

/* ============================================================
   RESET & BASE
   ============================================================ */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: var(--font-stack); color: var(--text-color); background: var(--bg-page); line-height: 1.7; }
a { color: var(--color-blue); text-decoration: none; }
a:hover { text-decoration: underline; }
ul { list-style: none; }
img { max-width: 100%; }

/* ============================================================
   HEADER
   ============================================================ */
.site-header {
  position: fixed; top: 0; left: 0; right: 0;
  height: var(--header-height);
  background: var(--color-blue);
  color: white;
  display: flex; align-items: center;
  padding: 0 1.5rem;
  z-index: 100;
  box-shadow: 0 2px 6px rgba(0,0,0,0.2);
}
.site-title { color: white; display: flex; flex-direction: column; gap: 2px; }
.site-title-main { font-size: 1rem; font-weight: 700; line-height: 1.2; }
.site-title-sub { font-size: 0.68rem; opacity: 0.75; font-style: italic; }
.nav-toggle { display: none; background: none; border: none; color: white; font-size: 1.5rem; cursor: pointer; margin-left: auto; }

/* ============================================================
   LAYOUT
   ============================================================ */
.layout { display: flex; margin-top: var(--header-height); min-height: calc(100vh - var(--header-height)); }

/* ============================================================
   SIDEBAR
   ============================================================ */
.sidebar {
  width: var(--sidebar-width);
  background: var(--color-blue);
  color: white;
  position: fixed;
  top: var(--header-height); bottom: 0; left: 0;
  overflow-y: auto;
  padding: 1.25rem 0;
  z-index: 90;
  transition: transform 0.3s;
}
.nav-list { padding: 0; }
.nav-list > li > a {
  display: block;
  padding: 0.55rem 1.25rem;
  color: rgba(255,255,255,0.8);
  font-size: 0.85rem;
  border-left: 3px solid transparent;
  transition: all 0.2s;
}
.nav-list > li > a:hover,
.nav-list > li > a.active {
  color: white;
  border-left-color: var(--color-peach);
  background: rgba(255,255,255,0.1);
  text-decoration: none;
}
.nav-has-children > a { cursor: pointer; }
.nav-sub { background: rgba(0,0,0,0.18); max-height: 0; overflow: hidden; transition: max-height 0.35s ease; }
.nav-sub.open { max-height: 600px; }
.nav-sub li a { display: block; padding: 0.35rem 1.25rem 0.35rem 2.25rem; color: rgba(255,255,255,0.65); font-size: 0.78rem; }
.nav-sub li a:hover { color: white; text-decoration: none; }

/* ============================================================
   MAIN CONTENT
   ============================================================ */
.main-content { margin-left: var(--sidebar-width); padding: 2.5rem 3rem; max-width: 1060px; width: 100%; }

/* ============================================================
   TYPOGRAPHY
   ============================================================ */
.chapter-label { font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.12em; color: #ffffff; font-weight: 700; margin-bottom: 0.4rem; display: block; }
h1 { font-size: 2rem; color: var(--color-blue); margin-bottom: 1.5rem; line-height: 1.2; }
h2 { font-size: 1.3rem; color: var(--color-blue); margin: 2rem 0 0.75rem; padding-bottom: 0.4rem; border-bottom: 2px solid var(--color-blue-light); }
h3 { font-size: 1.05rem; color: var(--text-color); margin: 1.5rem 0 0.5rem; font-weight: 600; }
h4 { font-size: 0.9rem; color: var(--text-muted); font-weight: 700; margin: 1rem 0 0.4rem; }
p { margin-bottom: 1rem; }
ol.content-ol, ul.content-ul { padding-left: 1.5rem; margin-bottom: 1rem; }
ol.content-ol { list-style: decimal; }
ul.content-ul { list-style: disc; }
ol.content-ol li, ul.content-ul li { margin-bottom: 0.4rem; }

/* ============================================================
   CHAPTER HERO
   ============================================================ */
.chapter-hero {
  background: linear-gradient(135deg, var(--color-blue) 0%, #2d4f8a 100%);
  color: white; padding: 2rem 2.5rem; border-radius: var(--border-radius); margin-bottom: 2.5rem;
  display: grid; grid-template-columns: 60fr 25fr 15fr; align-items: center; gap: 1.5rem;
}
.chapter-hero .ch-icon { display: flex; justify-content: center; align-items: center; }
.chapter-hero .ch-icon img { width: 90px; height: 90px; object-fit: contain; }
.chapter-hero .ch-num {
  font-size: 4.5rem; font-weight: 900; opacity: 0.25; line-height: 1;
  text-align: center; color: white;
}
.chapter-hero h1 { color: white; margin-bottom: 0.4rem; font-size: 1.8rem; }
.chapter-hero .hero-sub { opacity: 0.85; font-size: 0.95rem; margin-bottom: 0; }

/* ============================================================
   INFO BOX (Bonus-Wissen)
   ============================================================ */
.info-box {
  background: var(--color-peach-bg); border-left: 4px solid var(--color-peach);
  border-radius: var(--border-radius); padding: 1rem 1.25rem; margin: 1.5rem 0;
}
.info-box .info-label { display: block; font-weight: 700; color: #8a3000; margin-bottom: 0.4rem; font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.06em; }
.info-box p { margin-bottom: 0.4rem; font-size: 0.875rem; }
.info-box a { color: var(--color-red); font-weight: 600; }

/* ============================================================
   FAZIT BOX
   ============================================================ */
.fazit-box {
  background: var(--color-green-bg); border-left: 4px solid var(--color-green);
  border-radius: var(--border-radius); padding: 1.25rem 1.5rem; margin: 2rem 0;
}
.fazit-box > .fazit-label { display: block; font-size: 0.75rem; font-weight: 700; color: var(--color-green); text-transform: uppercase; letter-spacing: 0.08em; margin-bottom: 0.5rem; }

/* ============================================================
   EXAMPLE BLOCK
   ============================================================ */
.example-block {
  background: var(--bg-white); border-left: 4px solid var(--color-blue);
  border-radius: var(--border-radius); padding: 1.25rem 1.5rem; margin: 1.5rem 0; box-shadow: var(--shadow);
}
.example-block .example-label { font-size: 0.75rem; font-weight: 700; color: var(--color-blue); text-transform: uppercase; letter-spacing: 0.08em; margin-bottom: 0.75rem; display: block; }

/* ============================================================
   SMART CARDS
   ============================================================ */
.smart-cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 1rem; margin: 1.5rem 0; }
.smart-card { background: var(--color-blue-bg); border: 1px solid var(--color-blue-light); border-radius: var(--border-radius); padding: 1rem 1.25rem; }
.smart-card .smart-num { font-size: 0.72rem; font-weight: 700; color: var(--color-red); text-transform: uppercase; letter-spacing: 0.06em; margin-bottom: 0.4rem; display: block; }
.smart-card p { font-size: 0.875rem; margin-bottom: 0; font-style: italic; color: var(--text-color); }

/* ============================================================
   TWO-COLUMN LAYOUT
   ============================================================ */
.two-col { display: grid; grid-template-columns: 2fr 1.5fr; gap: 2rem; align-items: start; margin: 1.5rem 0; }

/* ============================================================
   FLOWCHART (CSS-based)
   ============================================================ */
.flowchart { background: var(--bg-white); border-radius: var(--border-radius); padding: 1.25rem; box-shadow: var(--shadow); border: 1px solid var(--color-blue-light); }
.flowchart-title { font-size: 0.75rem; font-weight: 700; color: var(--text-muted); text-transform: uppercase; letter-spacing: 0.08em; margin-bottom: 1rem; }
.fc-item { display: flex; align-items: center; gap: 0.75rem; background: var(--color-blue); color: white; border-radius: 4px; padding: 0.6rem 0.9rem; font-size: 0.82rem; font-weight: 600; margin-bottom: 0.2rem; }
.fc-icon { font-size: 1.1rem; flex-shrink: 0; }
.fc-arrow { text-align: center; color: var(--color-blue); font-size: 1.1rem; line-height: 1; margin-bottom: 0.2rem; }

/* ============================================================
   COMPARISON GRID (Formativ/Summativ)
   ============================================================ */
.comparison-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1.5rem; margin: 1.5rem 0; }
.comparison-card { background: var(--bg-white); border-radius: var(--border-radius); padding: 1.5rem; box-shadow: var(--shadow); }
.comparison-card.formativ { border-top: 4px solid var(--color-green); }
.comparison-card.summativ { border-top: 4px solid var(--color-blue); }
.comparison-card > h3 { margin-top: 0; }
.comparison-card.formativ > h3 { color: var(--color-green); }
.comparison-card.summativ > h3 { color: var(--color-blue); }
.pro-con { margin: 0.75rem 0; }
.pro-con h4 { font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.06em; margin-bottom: 0.5rem; color: var(--text-muted); }
.pro-con ul { list-style: disc; padding-left: 1.25rem; }
.pro-con ul li { font-size: 0.85rem; margin-bottom: 0.3rem; }

/* ============================================================
   STRATEGY CARDS
   ============================================================ */
.strategy-cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 1rem; margin: 1.5rem 0; }
.strategy-card { background: var(--bg-white); border-radius: var(--border-radius); padding: 1.25rem; box-shadow: var(--shadow); border-top: 3px solid var(--color-blue); }
.strategy-card .s-num { font-size: 1.75rem; font-weight: 900; color: var(--color-blue-light); line-height: 1; margin-bottom: 0.4rem; }
.strategy-card h3 { margin-top: 0; font-size: 1rem; color: var(--color-blue); }
.strategy-card p { font-size: 0.85rem; margin-bottom: 0; color: var(--text-muted); }

/* ============================================================
   ACCORDION
   ============================================================ */
.accordion { margin: 1rem 0; }
.accordion-header {
  width: 100%; text-align: left; background: var(--color-blue); color: white;
  border: none; padding: 0.9rem 1.25rem; font-size: 0.95rem; font-weight: 600;
  cursor: pointer; border-radius: var(--border-radius); display: flex;
  justify-content: space-between; align-items: center; margin-bottom: 2px; transition: background 0.2s;
  font-family: var(--font-stack);
}
.accordion-header:hover { background: #2d4f8a; }
.acc-arrow { transition: transform 0.3s; display: inline-block; }
.accordion-header.open .acc-arrow { transform: rotate(180deg); }
.accordion-body { max-height: 0; overflow: hidden; transition: max-height 0.4s ease; }
.accordion-body.open { max-height: 3000px; }
.accordion-body-inner { padding: 1.25rem 1.5rem; background: var(--bg-white); border: 1px solid var(--color-blue-light); border-top: none; border-radius: 0 0 var(--border-radius) var(--border-radius); }

/* ============================================================
   CHECKLIST
   ============================================================ */
.checklist-group { margin: 1.5rem 0; }
.checklist-group h3 { margin-bottom: 0.75rem; }
.checklist-item { display: flex; align-items: flex-start; gap: 0.75rem; padding: 0.65rem 0; border-bottom: 1px solid var(--color-blue-light); }
.checklist-item:last-child { border-bottom: none; }
.checklist-item input[type="checkbox"] { margin-top: 0.25rem; width: 1.1rem; height: 1.1rem; cursor: pointer; accent-color: var(--color-green); flex-shrink: 0; }
.checklist-item label { cursor: pointer; font-size: 0.9rem; }
.checklist-item input:checked + label { text-decoration: line-through; color: var(--text-muted); }

/* ============================================================
   INDEX HERO
   ============================================================ */
.hero { background: linear-gradient(135deg, var(--color-blue) 0%, #2d4f8a 100%); color: white; padding: 3rem; border-radius: var(--border-radius); margin-bottom: 2.5rem; }
.hero-eyebrow { font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.15em; opacity: 0.65; margin-bottom: 0.6rem; }
.hero h1 { font-size: 2.25rem; color: white; margin-bottom: 0.75rem; line-height: 1.15; }
.hero-subtitle { font-size: 1rem; opacity: 0.8; font-style: italic; margin-bottom: 1.5rem; }
.hero-body { opacity: 0.88; font-size: 0.93rem; line-height: 1.8; border-top: 1px solid rgba(255,255,255,0.2); padding-top: 1.5rem; }

/* ============================================================
   CHAPTER CARDS (index)
   ============================================================ */
.chapter-cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 1.25rem; margin: 2rem 0; }
.chapter-card { background: var(--bg-white); border-radius: var(--border-radius); padding: 1.5rem; box-shadow: var(--shadow); text-decoration: none; display: block; border-top: 4px solid var(--color-blue); transition: all 0.2s; }
.chapter-card:hover { transform: translateY(-3px); box-shadow: 0 6px 20px rgba(0,0,0,0.12); text-decoration: none; }
.chapter-card .card-num { font-size: 0.7rem; font-weight: 700; color: var(--color-red); text-transform: uppercase; letter-spacing: 0.12em; display: block; margin-bottom: 0.4rem; }
.chapter-card h2 { font-size: 1rem; margin: 0 0 0.5rem; color: var(--color-blue); border: none; padding: 0; }
.chapter-card p { font-size: 0.82rem; color: var(--text-muted); margin-bottom: 0; }

/* ============================================================
   ANHANG
   ============================================================ */
.anhang-subnav { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-bottom: 2.5rem; padding: 1.25rem; background: var(--bg-white); border-radius: var(--border-radius); border: 1px solid var(--color-blue-light); }
.anhang-subnav a { padding: 0.35rem 0.75rem; background: var(--color-blue-bg); border-radius: 3px; font-size: 0.78rem; color: var(--color-blue); font-weight: 600; transition: all 0.2s; }
.anhang-subnav a:hover { background: var(--color-blue); color: white; text-decoration: none; }
.anhang-section { margin-bottom: 3.5rem; scroll-margin-top: 80px; }
.section-tag { display: inline-block; background: var(--color-red); color: white; font-size: 0.68rem; font-weight: 700; padding: 0.2rem 0.6rem; border-radius: 3px; text-transform: uppercase; letter-spacing: 0.06em; margin-bottom: 0.5rem; }

/* ============================================================
   NUMBERED STEP LIST
   ============================================================ */
.step-list { counter-reset: steps; padding: 0; margin: 1rem 0; }
.step-list li { counter-increment: steps; display: flex; gap: 1rem; margin-bottom: 1rem; align-items: flex-start; }
.step-list li::before { content: counter(steps); background: var(--color-blue); color: white; min-width: 1.75rem; height: 1.75rem; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 0.8rem; font-weight: 700; flex-shrink: 0; margin-top: 0.15rem; }

/* ============================================================
   PAGE NAV (prev/next)
   ============================================================ */
.page-nav { display: flex; justify-content: space-between; margin-top: 3.5rem; padding-top: 1.5rem; border-top: 2px solid var(--color-blue-light); }
.page-nav a { display: flex; align-items: center; gap: 0.5rem; font-weight: 600; font-size: 0.875rem; color: var(--color-blue); padding: 0.6rem 1.1rem; border-radius: var(--border-radius); background: var(--bg-white); border: 1px solid var(--color-blue-light); transition: all 0.2s; }
.page-nav a:hover { background: var(--color-blue); color: white; text-decoration: none; }
.page-nav-placeholder { flex: 1; }

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 900px) {
  .nav-toggle { display: block; }
  .sidebar { transform: translateX(-100%); }
  .sidebar.open { transform: translateX(0); }
  .main-content { margin-left: 0; padding: 1.5rem; }
  .two-col { grid-template-columns: 1fr; }
  .comparison-grid { grid-template-columns: 1fr; }
  .chapter-cards { grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); }
}
@media (max-width: 520px) {
  .hero { padding: 1.75rem; }
  .hero h1 { font-size: 1.6rem; }
  .smart-cards, .strategy-cards, .chapter-cards { grid-template-columns: 1fr; }
  .main-content { padding: 1rem; }
}