/* HR-UniOS - Claude.com (Anthropic) Inspired Design System */
@import url('https://fonts.googleapis.com/css2?family=Instrument+Serif:ital@0;1&family=Plus+Jakarta+Sans:wght@400;500;600;700;800&family=Inter:wght@400;500;600&display=swap');

:root {
  /* Claude Warm Palette (Light Mode Default) */
  --bg-primary: #FBF9F5;
  --bg-secondary: #F5F2EB;
  --bg-card: #FFFFFF;
  --bg-card-hover: #FFFFFF;
  --border-color: #E8E4DC;
  --border-hover: #D97757;
  
  --accent-terracotta: #D97757;
  --accent-terracotta-hover: #C15C3D;
  --accent-terracotta-light: rgba(217, 119, 87, 0.12);
  
  --text-primary: #1F1E1B;
  --text-secondary: #5C5A54;
  --text-muted: #8C8880;
  
  --font-serif: 'Instrument Serif', Georgia, serif;
  --font-sans: 'Plus Jakarta Sans', 'Inter', sans-serif;
  
  --shadow-subtle: 0 4px 20px rgba(0, 0, 0, 0.03);
  --shadow-claude: 0 12px 40px rgba(31, 30, 27, 0.06);
  --shadow-focus: 0 0 0 4px rgba(217, 119, 87, 0.15);
  
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-full: 9999px;
  
  --transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Dark Mode Tokens */
[data-theme="dark"] {
  --bg-primary: #141312;
  --bg-secondary: #1C1B1A;
  --bg-card: #242321;
  --bg-card-hover: #2E2C29;
  --border-color: #383632;
  --border-hover: #D97757;
  
  --text-primary: #F5F3EF;
  --text-secondary: #B5B1A8;
  --text-muted: #78746C;
  
  --shadow-subtle: 0 4px 20px rgba(0, 0, 0, 0.3);
  --shadow-claude: 0 12px 40px rgba(0, 0, 0, 0.4);
}

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

html {
  scroll-behavior: smooth;
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

body {
  min-height: 100vh;
}

.container {
  max-width: 1160px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Header & Nav */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(251, 249, 245, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-color);
  padding: 16px 0;
}

[data-theme="dark"] .header {
  background: rgba(20, 19, 18, 0.85);
}

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

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-weight: 700;
  font-size: 1.3rem;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.brand-icon {
  width: 32px;
  height: 32px;
  background: var(--accent-terracotta);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #FFFFFF;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
}

.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
  transition: var(--transition);
}

.nav-link:hover {
  color: var(--text-primary);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

.theme-toggle {
  background: transparent;
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  width: 38px;
  height: 38px;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.theme-toggle:hover {
  background: var(--bg-secondary);
}

/* Primary Button CTA */
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--accent-terracotta);
  color: #FFFFFF;
  padding: 12px 24px;
  border-radius: var(--radius-full);
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  border: none;
  cursor: pointer;
  transition: var(--transition);
  box-shadow: 0 4px 14px rgba(217, 119, 87, 0.3);
}

.btn-primary:hover {
  background: var(--accent-terracotta-hover);
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(217, 119, 87, 0.4);
}

/* Hero Section (Claude Signature) */
.hero {
  padding: 80px 0 60px;
  text-align: center;
}

.hero-subtitle-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  border-radius: var(--radius-full);
  background: var(--accent-terracotta-light);
  color: var(--accent-terracotta);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 24px;
}

.hero-headline {
  font-family: var(--font-serif);
  font-size: clamp(2.8rem, 5.5vw, 4.8rem);
  font-weight: 400;
  line-height: 1.08;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
  color: var(--text-primary);
}

.hero-subhead {
  font-size: clamp(1.1rem, 2vw, 1.3rem);
  color: var(--text-secondary);
  max-width: 680px;
  margin: 0 auto 48px;
  font-weight: 400;
  line-height: 1.5;
}

/* Claude Signature Prompt Interface Box */
.claude-prompt-card {
  max-width: 760px;
  margin: 0 auto 60px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: var(--shadow-claude);
  text-align: left;
  transition: var(--transition);
}

.claude-prompt-card:focus-within {
  border-color: var(--accent-terracotta);
  box-shadow: var(--shadow-claude), var(--shadow-focus);
}

.prompt-input-area {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  margin-bottom: 20px;
}

.prompt-input-area textarea {
  width: 100%;
  border: none;
  background: transparent;
  outline: none;
  font-family: var(--font-sans);
  font-size: 1.1rem;
  color: var(--text-primary);
  resize: none;
  height: 60px;
}

.prompt-chips-label {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 12px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.prompt-chips-grid {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.prompt-chip {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  padding: 8px 16px;
  border-radius: var(--radius-full);
  font-size: 0.88rem;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.prompt-chip:hover, .prompt-chip.active {
  background: var(--accent-terracotta-light);
  border-color: var(--accent-terracotta);
  color: var(--accent-terracotta);
}

/* Prompt Response Output Window */
.prompt-output-box {
  margin-top: 20px;
  padding-top: 20px;
  border-top: 1px solid var(--border-color);
  font-size: 0.95rem;
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100px;
}

/* Claude Style Feature Cards Grid */
.features-section {
  padding: 80px 0;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}

.section-header {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 56px;
}

.section-tag {
  color: var(--accent-terracotta);
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 12px;
  display: block;
}

.section-title {
  font-family: var(--font-serif);
  font-size: clamp(2.2rem, 3.8vw, 3.2rem);
  font-weight: 400;
  line-height: 1.15;
  margin-bottom: 16px;
}

.section-desc {
  color: var(--text-secondary);
  font-size: 1.05rem;
}

.claude-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
}

.claude-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 36px 32px;
  transition: var(--transition);
  box-shadow: var(--shadow-subtle);
}

.claude-card:hover {
  border-color: var(--accent-terracotta);
  transform: translateY(-2px);
  box-shadow: var(--shadow-claude);
}

.card-icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: var(--accent-terracotta-light);
  color: var(--accent-terracotta);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

.card-title {
  font-family: var(--font-serif);
  font-size: 1.6rem;
  font-weight: 400;
  margin-bottom: 12px;
}

.card-text {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.6;
}

/* Interactive ROI Section */
.calculator-section {
  padding: 90px 0;
}

.calc-container {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 48px;
  box-shadow: var(--shadow-claude);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.range-slider {
  width: 100%;
  height: 8px;
  border-radius: 4px;
  background: var(--bg-secondary);
  outline: none;
  -webkit-appearance: none;
  margin-top: 16px;
}

.range-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--accent-terracotta);
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(217, 119, 87, 0.4);
}

.calc-display {
  font-family: var(--font-serif);
  font-size: 2.8rem;
  color: var(--accent-terracotta);
  margin-top: 6px;
}

/* FAQ Accordion */
.faq-section {
  padding: 80px 0 100px;
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  border-bottom: 1px solid var(--border-color);
  padding: 20px 0;
}

.faq-question {
  width: 100%;
  background: none;
  border: none;
  text-align: left;
  font-family: var(--font-serif);
  font-size: 1.4rem;
  color: var(--text-primary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, padding-top 0.3s ease;
  color: var(--text-secondary);
  font-size: 0.98rem;
  line-height: 1.6;
}

.faq-item.active .faq-answer {
  max-height: 200px;
  padding-top: 14px;
}

/* Claude Style Final Conversion Banner */
.cta-banner {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: 80px 0;
  text-align: center;
}

.cta-title {
  font-family: var(--font-serif);
  font-size: clamp(2.4rem, 4vw, 3.4rem);
  margin-bottom: 16px;
}

.footer {
  padding: 32px 0;
  border-top: 1px solid var(--border-color);
  color: var(--text-muted);
  font-size: 0.9rem;
  text-align: center;
}

@media (max-width: 768px) {
  .nav-links { display: none; }
  .calc-container { grid-template-columns: 1fr; gap: 32px; }
}