/* ========================================
   CSAP DevOps Compliance Checker - Styles
   ======================================== */

/* CSS Variables */
:root {
  --color-primary: #1E40AF;
  --color-primary-dark: #1a3a8a;
  --color-secondary: #579950;
  --color-secondary-dark: #3e6d38;
  --color-accent: #0ea5e9;
  --color-bg: #f8fafc;
  --color-surface: #ffffff;
  --color-text: #1e293b;
  --color-text-muted: #64748b;
  --color-border: #e2e8f0;
  --color-grade-low: #dc2626;
  --color-grade-mid: #f59e0b;
  --color-grade-high: #22c55e;
  --font-primary: 'Pretendard', 'Noto Sans KR', -apple-system, BlinkMacSystemFont, sans-serif;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1);
  --transition-fast: 0.15s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-primary);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* App Container */
.app-container {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
  animation: slideDown 0.5s ease;
}

@keyframes slideDown {
  from {
    transform: translateY(-100%);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

.header-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.logo-text {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-primary);
}

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

.nav-links a {
  text-decoration: none;
  color: var(--color-text-muted);
  font-weight: 500;
  transition: color var(--transition-fast);
}

.nav-links a:hover {
  color: var(--color-primary);
}

/* Hero Section */
.hero {
  position: relative;
  min-height: 480px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background: 
    radial-gradient(ellipse at 20% 30%, rgba(87, 153, 80, 0.12) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 70%, rgba(30, 64, 175, 0.08) 0%, transparent 50%),
    radial-gradient(ellipse at 50% 50%, rgba(62, 109, 56, 0.06) 0%, transparent 70%),
    linear-gradient(180deg, rgba(248, 250, 252, 0.3) 0%, rgba(248, 250, 252, 0) 100%);
  background-color: #f8fafc;
}

/* Animated grid pattern */
.hero-bg::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: 
    linear-gradient(rgba(87, 153, 80, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(87, 153, 80, 0.03) 1px, transparent 1px);
  background-size: 40px 40px;
  animation: gridMove 20s linear infinite;
}

@keyframes gridMove {
  0% { transform: translate(0, 0); }
  100% { transform: translate(40px, 40px); }
}

/* Floating particles */
.hero-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image: radial-gradient(circle at 20% 20%, rgba(87, 153, 80, 0.15) 0%, transparent 20%),
                    radial-gradient(circle at 80% 30%, rgba(30, 64, 175, 0.1) 0%, transparent 15%),
                    radial-gradient(circle at 60% 80%, rgba(62, 109, 56, 0.12) 0%, transparent 25%),
                    radial-gradient(circle at 40% 60%, rgba(87, 153, 80, 0.08) 0%, transparent 10%);
  animation: particleFloat 15s ease-in-out infinite;
}

@keyframes particleFloat {
  0%, 100% { opacity: 1; transform: translateY(0); }
  50% { opacity: 0.7; transform: translateY(-10px); }
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom, transparent 60%, var(--color-bg) 100%);
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: left;
  padding: 2rem 3rem;
  animation: fadeInUp 0.8s ease 0.2s both;
}

.hero-title { text-align: left; }
.hero-subtitle { text-align: left; }
.hero-badges { justify-content: flex-start; }
.hero-cta { justify-content: flex-start; }

@keyframes fadeInUp {
  from {
    transform: translateY(30px);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

.hero-title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1rem;
  color: var(--color-text);
}

.hero-title .highlight {
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--color-text-muted);
  margin-bottom: 1.5rem;
}

.hero-badges {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.75rem;
}

.badge {
  display: inline-block;
  padding: 0.5rem 1rem;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 50px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text-muted);
  box-shadow: var(--shadow-sm);
}

/* Main Content */
.main-content {
  flex: 1;
  max-width: 1000px;
  width: 100%;
  margin: 0 auto;
  padding: 3rem 1.5rem;
}

/* Input Section */
.input-section {
  animation: fadeIn 0.6s ease;
}

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

.section-header {
  text-align: center;
  margin-bottom: 2.5rem;
}

.section-header h2 {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.section-header p {
  color: var(--color-text-muted);
}

/* Form */
.diagnose-form {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--color-border);
}

.form-group {
  margin-bottom: 2rem;
}

.form-group:last-of-type {
  margin-bottom: 2.5rem;
}

.category-title {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--color-primary);
  display: inline-block;
}

.checkbox-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 0.75rem;
}

.checkbox-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.checkbox-item:hover {
  border-color: var(--color-primary);
  background: rgba(30, 64, 175, 0.05);
}

.checkbox-item input[type="checkbox"] {
  width: 18px;
  height: 18px;
  accent-color: var(--color-primary);
  cursor: pointer;
}

.checkbox-label {
  font-weight: 500;
  font-size: 0.9375rem;
}

/* Button */
.btn-diagnose {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  width: 100%;
  padding: 1rem 2rem;
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
  color: white;
  border: none;
  border-radius: var(--radius-md);
  font-size: 1.125rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-normal);
  box-shadow: var(--shadow-md);
}

.btn-diagnose:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-diagnose:active {
  transform: translateY(0);
}

.btn-diagnose svg {
  transition: transform var(--transition-fast);
}

.btn-diagnose:hover svg {
  transform: translateX(4px);
}

/* Results Section */
.results-section {
  animation: slideIn 0.5s ease;
}

@keyframes slideIn {
  from {
    transform: translateX(20px);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

.results-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
}

.results-header h2 {
  font-size: 1.75rem;
  font-weight: 700;
}

.btn-back {
  padding: 0.625rem 1.25rem;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
}

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

/* Grade Card */
.grade-card {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--color-border);
  margin-bottom: 2rem;
}

.grade-indicator {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}

.grade-circle {
  width: 100px;
  height: 100px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--color-border) 0%, var(--color-bg) 100%);
  border: 4px solid var(--color-border);
  transition: all var(--transition-normal);
}

.grade-letter {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--color-text-muted);
}

.grade-circle.grade-a {
  background: linear-gradient(135deg, #22c55e 0%, #16a34a 100%);
  border-color: #22c55e;
}
.grade-circle.grade-a .grade-letter { color: white; }

.grade-circle.grade-b {
  background: linear-gradient(135deg, #3b82f6 0%, #2563eb 100%);
  border-color: #3b82f6;
}
.grade-circle.grade-b .grade-letter { color: white; }

.grade-circle.grade-c {
  background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
  border-color: #f59e0b;
}
.grade-circle.grade-c .grade-letter { color: white; }

.grade-info h3 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 0.25rem;
}

.grade-info p {
  color: var(--color-text-muted);
}

/* Score Bar */
.score-bar {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.score-label {
  font-weight: 500;
  min-width: 80px;
}

.score-track {
  flex: 1;
  height: 12px;
  background: var(--color-border);
  border-radius: 6px;
  overflow: hidden;
}

.score-fill {
  height: 100%;
  width: 0;
  background: linear-gradient(90deg, var(--color-grade-low) 0%, var(--color-grade-mid) 50%, var(--color-grade-high) 100%);
  border-radius: 6px;
  transition: width 1s ease;
}

.score-value {
  font-weight: 700;
  font-size: 1.25rem;
  min-width: 60px;
  text-align: right;
}

/* Risks Section */
.risks-section {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-border);
  margin-bottom: 2rem;
}

.risks-section h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

.risk-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.risk-item {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 1rem;
  background: rgba(220, 38, 38, 0.05);
  border-left: 4px solid var(--color-grade-low);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.risk-item.medium {
  background: rgba(245, 158, 11, 0.05);
  border-left-color: var(--color-grade-mid);
}

.risk-icon {
  color: var(--color-grade-low);
  flex-shrink: 0;
}

.risk-item.medium .risk-icon {
  color: var(--color-grade-mid);
}

.risk-content {
  flex: 1;
}

.risk-title {
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.risk-description {
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

/* Alternatives Section */
.alternatives-section {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-border);
  margin-bottom: 2rem;
}

.alternatives-section h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

.alt-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1rem;
}

.alt-card {
  padding: 1.25rem;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.alt-card:hover {
  border-color: var(--color-secondary);
  transform: translateY(-2px);
}

.alt-category {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  color: var(--color-secondary);
  margin-bottom: 0.5rem;
}

.alt-name {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.alt-description {
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

/* Migration Section */
.migration-section {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-border);
}

.migration-section h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

.migration-card {
  padding: 1.5rem;
  background: linear-gradient(135deg, rgba(30, 64, 175, 0.05) 0%, rgba(14, 165, 233, 0.05) 100%);
  border-radius: var(--radius-md);
  text-align: center;
}

.migration-days {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--color-primary);
}

.migration-label {
  color: var(--color-text-muted);
}

/* Footer */
.footer {
  background: var(--color-text);
  color: white;
  padding: 3rem 1.5rem;
  margin-top: auto;
}

.footer-content {
  max-width: 1200px;
  margin: 0 auto;
  text-align: center;
}

.footer-brand {
  margin-bottom: 1.5rem;
}

.footer-logo {
  font-size: 1.5rem;
  font-weight: 700;
}

.footer-brand p {
  color: rgba(255,255,255,0.7);
  margin-top: 0.25rem;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 2rem;
  margin-bottom: 1.5rem;
}

.footer-links a {
  color: rgba(255,255,255,0.7);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.footer-links a:hover {
  color: white;
}

.copyright {
  color: rgba(255,255,255,0.5);
  font-size: 0.875rem;
}

/* Loading Overlay */
.loading-overlay {
  position: fixed;
  inset: 0;
  background: rgba(255, 255, 255, 0.9);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 1000;
}

.loading-spinner {
  width: 48px;
  height: 48px;
  border: 4px solid var(--color-border);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin-bottom: 1rem;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.loading-overlay p {
  font-size: 1.125rem;
  color: var(--color-text-muted);
}

/* Responsive */
@media (max-width: 768px) {
  .hero {
    min-height: 360px;
  }
  
  .hero-title {
    font-size: 2rem;
  }
  
  .hero-subtitle {
    font-size: 1rem;
  }
  
  .checkbox-grid {
    grid-template-columns: 1fr;
  }
  
  .diagnose-form {
    padding: 1.5rem;
  }
  
  .grade-indicator {
    flex-direction: column;
    text-align: center;
  }
  
  .score-bar {
    flex-direction: column;
    text-align: center;
  }
  
  .alt-grid {
    grid-template-columns: 1fr;
  }
  
  .features-grid {
    grid-template-columns: 1fr;
  }
}

/* Hero CTA Button */
.hero-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 1.5rem;
  padding: 0.875rem 1.75rem;
  background: linear-gradient(135deg, var(--color-secondary) 0%, var(--color-secondary-dark) 100%);
  color: white;
  text-decoration: none;
  border: none;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 1rem;
  transition: all var(--transition-normal);
  box-shadow: var(--shadow-md);
  cursor: pointer;
}

.hero-cta:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.hero-cta svg {
  transition: transform var(--transition-fast);
}

.hero-cta:hover svg {
  transform: translateX(4px);
}

/* Features Section */
.features-section {
  padding: 4rem 1.5rem;
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
}

.features-container {
  max-width: 1100px;
  margin: 0 auto;
}

.features-header {
  text-align: center;
  margin-bottom: 3rem;
}

.features-tag {
  display: inline-block;
  padding: 0.375rem 0.875rem;
  background: rgba(87, 153, 80, 0.1);
  color: var(--color-secondary-dark);
  font-size: 0.8125rem;
  font-weight: 600;
  border-radius: 50px;
  margin-bottom: 1rem;
}

.features-header h2 {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--color-text);
}

/* Asymmetric Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 1.5rem;
}

.feature-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  /* Asymmetric placement - varies by card type */
}

.feature-card-1 { grid-column: span 3; }
.feature-card-2 { grid-column: span 3; }
.feature-card-3 { grid-column: span 3; }
.feature-card-4 { grid-column: span 3; }

/* Desktop: 2x2 with varied heights */
@media (min-width: 1024px) {
  .feature-card-1 { grid-column: span 4; }
  .feature-card-2 { grid-column: span 4; }
  .feature-card-3 { grid-column: span 4; }
  .feature-card-4 { grid-column: span 4; }
}

.feature-card {
  animation: fadeInUp 0.6s ease both;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-secondary);
}

.feature-card-1 { animation-delay: 0.1s; }
.feature-card-2 { animation-delay: 0.2s; }
.feature-card-3 { animation-delay: 0.3s; }
.feature-card-4 { animation-delay: 0.4s; }

.feature-icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, rgba(87, 153, 80, 0.15) 0%, rgba(62, 109, 56, 0.1) 100%);
  border-radius: var(--radius-md);
  margin-bottom: 1rem;
  color: var(--color-secondary-dark);
}

.feature-card h3 {
  font-size: 1.0625rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--color-text);
}

.feature-card p {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  line-height: 1.5;
}

/* Mobile features grid asymmetric */
@media (max-width: 900px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .feature-card-2 {
    transform: translateY(1rem);
  }
  
  .feature-card-4 {
    transform: translateY(1rem);
  }
}