/* ============================================================
   CSAP DevOps Stack Compatibility Checker — Styles
   Design: Impeccable zero-decoration minimalism
   Canvas: #ffffff | Ink: #000000 | Signal: #0052cc
   Font: Pretendard 400/700
   Spacing: 4px grid | Radius: 4px only
   ============================================================ */

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

:root {
  --canvas: #ffffff;
  --ink: #000000;
  --signal: #0052cc;
  --signal-hover: #003d99;
  --border: #e5e5e5;
  --border-light: #f0f0f0;
  --text-secondary: #4a4a4a;
  --bg-muted: #fafafa;
  --certified: #076b07;
  --partial: #b8860b;
  --reviewing: #0052cc;
  --not-certified: #c41e3a;
  --radius: 4px;
  --font: 'Pretendard', -apple-system, 'Segoe UI', sans-serif;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
}

body {
  font-family: var(--font);
  font-weight: 400;
  font-size: 16px;
  line-height: 1.6;
  color: var(--ink);
  background: var(--canvas);
}

.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ============================================================
   Animations
   ============================================================ */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideInLeft {
  from { opacity: 0; transform: translateX(-32px); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes countUp {
  from { opacity: 0; transform: scale(0.8); }
  to { opacity: 1; transform: scale(1); }
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.6; }
}

@keyframes scoreReveal {
  0% { stroke-dashoffset: 283; }
}

.animate-in {
  animation: fadeInUp 0.5s ease-out both;
}

/* ============================================================
   Hero Section — Asymmetric layout
   ============================================================ */
.hero {
  padding: 64px 0;
  border-bottom: 1px solid var(--border);
}

.hero-content {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 48px;
  align-items: center;
}

.hero-eyebrow {
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--signal);
  margin-bottom: 12px;
  animation: fadeIn 0.4s ease-out both;
}

.hero-title {
  font-size: 48px;
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
  animation: fadeInUp 0.5s ease-out 0.1s both;
}

.hero-desc {
  font-size: 17px;
  line-height: 1.7;
  color: var(--text-secondary);
  margin-bottom: 32px;
  max-width: 520px;
  animation: fadeInUp 0.5s ease-out 0.2s both;
}

.hero-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 32px;
  margin-bottom: 32px;
  animation: fadeInUp 0.5s ease-out 0.3s both;
}

.stat-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.stat-num {
  font-size: 24px;
  font-weight: 700;
  color: var(--signal);
  animation: countUp 0.4s ease-out both;
}

.stat-label {
  font-size: 13px;
  color: var(--text-secondary);
}

.hero-image {
  position: relative;
  animation: fadeIn 0.6s ease-out 0.4s both;
}

.hero-image img {
  width: 100%;
  height: 360px;
  object-fit: cover;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  display: block;
}

.img-credit {
  display: block;
  font-size: 12px;
  color: var(--text-secondary);
  margin-top: 8px;
  text-align: right;
}

.img-credit a {
  color: var(--text-secondary);
  text-decoration: underline;
}

/* ============================================================
   CTA Buttons
   ============================================================ */
.cta-btn {
  display: inline-block;
  padding: 14px 32px;
  font-family: var(--font);
  font-size: 16px;
  font-weight: 700;
  line-height: 1;
  text-decoration: none;
  color: var(--canvas);
  background: var(--ink);
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  transition: background 0.15s, transform 0.1s;
  animation: fadeInUp 0.5s ease-out 0.4s both;
}

.cta-btn:hover {
  background: var(--signal);
}

.cta-btn:active {
  transform: scale(0.98);
}

.cta-btn:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: 2px;
}

.cta-btn.outline {
  background: transparent;
  color: var(--ink);
  border: 2px solid var(--ink);
}

.cta-btn.outline:hover {
  background: var(--ink);
  color: var(--canvas);
}

.cta-link {
  display: inline-block;
  font-size: 16px;
  font-weight: 700;
  color: var(--signal);
  text-decoration: none;
  border-bottom: 2px solid var(--signal);
  padding-bottom: 2px;
  transition: color 0.15s;
}

.cta-link:hover {
  color: var(--signal-hover);
  border-bottom-color: var(--signal-hover);
}

/* ============================================================
   Problem Section
   ============================================================ */
.problem-section {
  padding: 64px 0;
  background: var(--bg-muted);
  border-bottom: 1px solid var(--border);
}

.section-title {
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin-bottom: 40px;
  text-align: center;
}

.section-title.left {
  text-align: left;
}

.section-desc {
  font-size: 16px;
  color: var(--text-secondary);
  text-align: center;
  margin-top: -28px;
  margin-bottom: 40px;
}

.problem-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr 1fr;
  gap: 24px;
}

.problem-card {
  background: var(--canvas);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px 28px;
  transition: border-color 0.2s, transform 0.2s;
}

.problem-card:hover {
  border-color: var(--signal);
  transform: translateY(-4px);
}

.card-num {
  display: block;
  font-size: 13px;
  font-weight: 700;
  color: var(--signal);
  letter-spacing: 0.05em;
  margin-bottom: 12px;
}

.problem-card h3 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 12px;
}

.problem-card p {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* ============================================================
   Checker Tool Section
   ============================================================ */
.checker-section {
  padding: 64px 0;
}

/* Category Tabs */
.category-tabs {
  display: flex;
  gap: 8px;
  margin-bottom: 32px;
  flex-wrap: wrap;
}

.tab-btn {
  padding: 14px 20px;
  font-family: var(--font);
  font-size: 14px;
  font-weight: 700;
  color: var(--text-secondary);
  background: transparent;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.15s;
}

.tab-btn:hover {
  border-color: var(--ink);
  color: var(--ink);
}

.tab-btn.active {
  background: var(--ink);
  color: var(--canvas);
  border-color: var(--ink);
}

/* Tool Grid */
.tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 12px;
  margin-bottom: 32px;
}

.tool-card {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.15s;
  user-select: none;
  background: var(--canvas);
}

.tool-card:hover {
  border-color: var(--ink);
}

.tool-card:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: 2px;
}

.tool-card.selected {
  border-color: var(--signal);
  background: #f0f5ff;
}

.tool-card.hidden {
  display: none;
}

.tool-checkbox {
  width: 20px;
  height: 20px;
  border: 2px solid var(--border);
  border-radius: var(--radius);
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.15s;
}

.tool-card.selected .tool-checkbox {
  background: var(--signal);
  border-color: var(--signal);
}

.tool-checkbox::after {
  content: '';
  width: 6px;
  height: 10px;
  border: solid var(--canvas);
  border-width: 0 2px 2px 0;
  transform: rotate(45deg) translate(-1px, -1px);
  opacity: 0;
  transition: opacity 0.1s;
}

.tool-card.selected .tool-checkbox::after {
  opacity: 1;
}

.tool-info {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
}

.tool-name {
  font-size: 15px;
  font-weight: 700;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.tool-category-label {
  font-size: 12px;
  color: var(--text-secondary);
}

/* Check Button */
.check-action {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 48px;
}

.check-btn {
  padding: 16px 40px;
  font-family: var(--font);
  font-size: 16px;
  font-weight: 700;
  color: var(--canvas);
  background: var(--ink);
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.15s;
}

.check-btn:disabled {
  background: var(--border);
  color: var(--text-secondary);
  cursor: not-allowed;
}

.check-btn:not(:disabled):hover {
  background: var(--signal);
}

.check-btn:not(:disabled):active {
  transform: scale(0.98);
}

.selected-count {
  font-size: 14px;
  color: var(--text-secondary);
}

/* ============================================================
   Results Panel
   ============================================================ */
.results-panel {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  animation: fadeInUp 0.4s ease-out;
}

.results-panel[hidden] {
  display: none;
}

.results-header {
  background: var(--bg-muted);
  padding: 32px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--border);
}

.results-header h3 {
  font-size: 24px;
  font-weight: 700;
}

.results-summary {
  display: flex;
  align-items: center;
  gap: 20px;
}

.score-circle {
  position: relative;
  width: 80px;
  height: 80px;
}

.score-circle svg {
  width: 80px;
  height: 80px;
  transform: rotate(-90deg);
}

.score-circle .bg {
  fill: none;
  stroke: var(--border);
  stroke-width: 6;
}

.score-circle .fg {
  fill: none;
  stroke: var(--signal);
  stroke-width: 6;
  stroke-linecap: round;
  stroke-dasharray: 283;
  stroke-dashoffset: 283;
  transition: stroke-dashoffset 1s ease-out;
}

.score-circle .score-text {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  font-weight: 700;
}

.score-label {
  font-size: 14px;
  color: var(--text-secondary);
}

.score-label strong {
  display: block;
  font-size: 16px;
  color: var(--ink);
}

/* Results Detail */
.results-detail {
  padding: 0;
}

.result-row {
  display: grid;
  grid-template-columns: 200px 140px 1fr 120px;
  align-items: center;
  padding: 20px 32px;
  border-bottom: 1px solid var(--border-light);
  gap: 16px;
  animation: fadeIn 0.3s ease-out both;
}

.result-row:last-child {
  border-bottom: none;
}

.result-tool-name {
  font-size: 15px;
  font-weight: 700;
}

.result-category {
  font-size: 13px;
  color: var(--text-secondary);
}

.result-detail {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.5;
}

.result-badge {
  display: inline-block;
  padding: 6px 12px;
  font-size: 13px;
  font-weight: 700;
  border-radius: var(--radius);
  text-align: center;
  min-width: 80px;
}

.badge-certified {
  background: #e8f5e8;
  color: #065f06;
}

.badge-partial {
  background: #fdf6e3;
  color: #7a5a08;
}

.badge-reviewing {
  background: #f0f5ff;
  color: var(--reviewing);
}

.badge-not-certified {
  background: #fde8ec;
  color: var(--not-certified);
}

/* Results Actions */
.results-actions {
  display: flex;
  gap: 12px;
  padding: 24px 32px;
  border-top: 1px solid var(--border);
  background: var(--bg-muted);
}

.action-btn {
  padding: 15px 24px;
  font-family: var(--font);
  font-size: 14px;
  font-weight: 700;
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.15s;
}

.action-btn.primary {
  background: var(--ink);
  color: var(--canvas);
  border: none;
}

.action-btn.primary:hover {
  background: var(--signal);
}

.action-btn.secondary {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--border);
}

.action-btn.secondary:hover {
  border-color: var(--ink);
}

/* Results CTA */
.results-cta {
  padding: 24px 32px;
  border-top: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-muted);
}

.results-cta p {
  font-size: 15px;
  color: var(--text-secondary);
}

/* ============================================================
   Features Section — Asymmetric
   ============================================================ */
.features-section {
  padding: 64px 0;
  border-top: 1px solid var(--border);
}

.features-layout {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 48px;
  align-items: start;
}

.features-image {
  position: relative;
}

.features-image img {
  width: 100%;
  height: 420px;
  object-fit: cover;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  display: block;
}

.features-list .section-title {
  text-align: left;
  margin-bottom: 32px;
}

.feature-items {
  list-style: none;
}

.feature-items li {
  padding: 20px 0;
  border-bottom: 1px solid var(--border-light);
}

.feature-items li:last-child {
  border-bottom: none;
}

.feature-items strong {
  display: block;
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 6px;
}

.feature-items p {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ============================================================
   FAQ Section
   ============================================================ */
.faq-section {
  padding: 64px 0;
  background: var(--bg-muted);
  border-top: 1px solid var(--border);
}

.faq-list {
  max-width: 720px;
  margin: 0 auto;
}

.faq-item {
  border-bottom: 1px solid var(--border);
  background: var(--canvas);
}

.faq-item summary {
  padding: 20px 24px;
  font-size: 16px;
  font-weight: 700;
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: color 0.15s;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  content: '+';
  font-size: 20px;
  font-weight: 400;
  color: var(--text-secondary);
  transition: transform 0.2s;
}

.faq-item[open] summary::after {
  content: '\2212';
}

.faq-item summary:hover {
  color: var(--signal);
}

.faq-item p {
  padding: 0 24px 20px;
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ============================================================
   Footer CTA
   ============================================================ */
.footer-cta {
  padding: 80px 0;
  text-align: center;
  border-top: 1px solid var(--border);
}

.footer-cta h2 {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 12px;
}

.footer-cta p {
  font-size: 17px;
  color: var(--text-secondary);
  margin-bottom: 32px;
}

/* ============================================================
   Footer
   ============================================================ */
.site-footer {
  padding: 32px 0;
  border-top: 1px solid var(--border);
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.footer-brand {
  font-size: 14px;
  font-weight: 700;
}

.footer-copy {
  font-size: 13px;
  color: var(--text-secondary);
}

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 768px) {
  .hero-content {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .hero-title {
    font-size: 32px;
  }

  .hero-stats {
    gap: 20px;
  }

  .stat-num {
    font-size: 20px;
  }

  .hero-image img {
    height: 240px;
  }

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

  .features-layout {
    grid-template-columns: 1fr;
  }

  .features-image img {
    height: 280px;
  }

  .result-row {
    grid-template-columns: 1fr;
    gap: 8px;
    padding: 16px 20px;
  }

  .results-header {
    flex-direction: column;
    gap: 20px;
    align-items: flex-start;
  }

  .results-cta {
    flex-direction: column;
    gap: 12px;
    text-align: center;
  }

  .footer-content {
    flex-direction: column;
    gap: 8px;
    text-align: center;
  }

  .section-title {
    font-size: 24px;
  }

  .footer-cta h2 {
    font-size: 24px;
  }

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

@media (max-width: 480px) {
  .tool-grid {
    grid-template-columns: 1fr;
  }

  .category-tabs {
    gap: 4px;
  }

  .tab-btn {
    padding: 12px 12px;
    font-size: 13px;
  }
}