/* ============================================
   RentCalc 2.0 — Unified Styles
   Modern Fintech Aesthetic
   ============================================ */

/* === CSS Reset & Base === */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  /* Color Palette - Modern Fintech */
  --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --primary-color: #667eea;
  --primary-dark: #5568d3;
  --secondary-color: #764ba2;
  --accent-color: #48bb78;
  --accent-hover: #38a169;

  /* Neutrals */
  --bg-primary: #ffffff;
  --bg-secondary: #f7fafc;
  --bg-card: #ffffff;
  --text-primary: #2d3748;
  --text-secondary: #718096;
  --text-light: #a0aec0;
  --border-color: #e2e8f0;

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
  --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.12);

  /* Typography */
  --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-heading: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  --spacing-2xl: 4rem;

  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
  --transition-slow: 350ms ease;
}

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

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

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

/* === Typography System === */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
}

h1 {
  font-size: 2.5rem;
  font-weight: 800;
  letter-spacing: -0.02em;
}

h2 {
  font-size: 2rem;
  font-weight: 700;
}

h3 {
  font-size: 1.5rem;
  font-weight: 600;
}

h4 {
  font-size: 1.25rem;
  font-weight: 600;
}

p {
  margin-bottom: var(--spacing-sm);
  color: var(--text-secondary);
  line-height: 1.7;
}

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

a:hover {
  color: var(--primary-dark);
}

/* === Container & Layout === */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.container-narrow {
  max-width: 800px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

/* === Header & Navigation === */
.header {
  background: var(--bg-primary);
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(10px);
  background: rgba(255, 255, 255, 0.95);
}

.header-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--spacing-sm) var(--spacing-md);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 1.5rem;
  font-weight: 800;
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-menu {
  display: flex;
  gap: var(--spacing-lg);
  list-style: none;
}

.nav-menu a {
  color: var(--text-primary);
  font-weight: 500;
  transition: all var(--transition-fast);
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
}

.nav-menu a:hover {
  color: var(--primary-color);
  background: rgba(102, 126, 234, 0.08);
}

.nav-menu a.active {
  color: var(--primary-color);
  background: rgba(102, 126, 234, 0.1);
}

/* Mobile Menu Toggle */
.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 0.25rem;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-xs);
}

.menu-toggle span {
  width: 1.5rem;
  height: 2px;
  background: var(--text-primary);
  transition: all var(--transition-normal);
}

/* === Footer === */
.footer {
  background: var(--text-primary);
  color: var(--bg-primary);
  padding: var(--spacing-xl) 0 var(--spacing-lg);
  margin-top: var(--spacing-2xl);
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: var(--spacing-xl);
}

.footer-about h3 {
  color: var(--bg-primary);
  margin-bottom: var(--spacing-sm);
}

.footer-about p {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.95rem;
}

.footer-links h4 {
  color: var(--bg-primary);
  font-size: 1rem;
  margin-bottom: var(--spacing-sm);
}

.footer-links ul {
  list-style: none;
}

.footer-links a {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.9rem;
  transition: color var(--transition-fast);
  display: block;
  margin-bottom: 0.5rem;
}

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

.footer-bottom {
  text-align: center;
  margin-top: var(--spacing-lg);
  padding-top: var(--spacing-md);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  color: rgba(255, 255, 255, 0.6);
  font-size: 0.875rem;
}

/* === Buttons === */
.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-normal);
  border: none;
  font-size: 1rem;
  text-align: center;
  font-family: var(--font-primary);
}

.btn-primary {
  background: var(--primary-gradient);
  color: white;
  box-shadow: var(--shadow-md);
}

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

.btn-secondary {
  background: var(--bg-primary);
  color: var(--primary-color);
  border: 2px solid var(--primary-color);
}

.btn-secondary:hover {
  background: var(--primary-color);
  color: white;
}

.btn-accent {
  background: var(--accent-color);
  color: white;
}

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

.btn-lg {
  padding: 1rem 2rem;
  font-size: 1.125rem;
}

/* === Cards === */
.card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  padding: var(--spacing-lg);
  transition: all var(--transition-normal);
}

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

/* === Forms === */
.form-group {
  margin-bottom: var(--spacing-md);
}

.form-label {
  display: block;
  font-weight: 600;
  margin-bottom: var(--spacing-xs);
  color: var(--text-primary);
  font-size: 0.95rem;
}

.form-input {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 2px solid var(--border-color);
  border-radius: var(--radius-md);
  font-size: 1rem;
  font-family: var(--font-primary);
  transition: all var(--transition-fast);
  background: var(--bg-primary);
}

.form-input:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.form-input::placeholder {
  color: var(--text-light);
}

.input-group {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-md);
}

/* === Calculator Specific === */
.hero {
  background: var(--primary-gradient);
  color: white;
  padding: var(--spacing-2xl) 0;
  text-align: center;
}

.hero h1 {
  color: white;
  margin-bottom: var(--spacing-sm);
}

.hero p {
  color: rgba(255, 255, 255, 0.9);
  font-size: 1.125rem;
  max-width: 800px;
  margin: 0 auto;
}

.calculator-section {
  padding: var(--spacing-2xl) 0;
}

.calculator-card {
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl);
  padding: var(--spacing-xl);
  margin: -3rem auto 0;
  max-width: 900px;
  position: relative;
}

.mode-toggle {
  display: flex;
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  padding: 0.25rem;
  margin-bottom: var(--spacing-lg);
}

.mode-btn {
  flex: 1;
  padding: 0.75rem;
  background: transparent;
  border: none;
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  border-radius: var(--radius-md);
  transition: all var(--transition-normal);
}

.mode-btn.active {
  background: white;
  color: var(--primary-color);
  box-shadow: var(--shadow-sm);
}

.pro-section {
  margin-top: var(--spacing-lg);
  padding-top: var(--spacing-lg);
  border-top: 2px dashed var(--border-color);
}

.results {
  margin-top: var(--spacing-xl);
  padding: var(--spacing-lg);
  background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
  border-radius: var(--radius-lg);
  border: 2px solid rgba(102, 126, 234, 0.1);
}

.results.hidden {
  display: none;
}

.result-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-md);
  margin-top: var(--spacing-md);
}

.result-item {
  text-align: center;
  padding: var(--spacing-md);
  background: white;
  border-radius: var(--radius-md);
}

.result-label {
  font-size: 0.875rem;
  color: var(--text-secondary);
  font-weight: 500;
  margin-bottom: 0.25rem;
}

.result-value {
  font-size: 1.75rem;
  font-weight: 700;
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* === Blog Specific === */
.blog-hero {
  background: var(--primary-gradient);
  color: white;
  padding: var(--spacing-xl) 0;
  text-align: center;
}

.blog-hero h1 {
  color: white;
}

.blog-hero p {
  color: rgba(255, 255, 255, 0.9);
  font-size: 1.125rem;
  max-width: 600px;
  margin: 0 auto;
}

.blog-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: var(--spacing-lg);
  padding: var(--spacing-2xl) 0;
}

.blog-card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  overflow: hidden;
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
}

.blog-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-xl);
}

.blog-card-content {
  padding: var(--spacing-lg);
  flex: 1;
  display: flex;
  flex-direction: column;
}

.blog-card-meta {
  display: flex;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-sm);
  flex-wrap: wrap;
}

.blog-tag {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  background: rgba(102, 126, 234, 0.1);
  color: var(--primary-color);
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
}

.blog-date {
  font-size: 0.875rem;
  color: var(--text-light);
}

.blog-card h3 {
  font-size: 1.25rem;
  margin-bottom: var(--spacing-sm);
  line-height: 1.3;
}

.blog-card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-bottom: var(--spacing-md);
  flex: 1;
}

.blog-card-actions {
  display: flex;
  gap: var(--spacing-sm);
}

.blog-card-actions .btn {
  flex: 1;
  padding: 0.625rem 1rem;
  font-size: 0.9rem;
}

/* === Article Page === */
.article {
  padding: var(--spacing-2xl) 0;
}

.article-header {
  background: var(--primary-gradient);
  color: white;
  padding: var(--spacing-xl) 0;
  margin-bottom: var(--spacing-xl);
}

.article-header h1 {
  color: white;
  font-size: 2.5rem;
  margin-bottom: var(--spacing-sm);
}

.article-meta {
  display: flex;
  gap: var(--spacing-md);
  align-items: center;
  color: rgba(255, 255, 255, 0.9);
}

.article-content {
  max-width: 740px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
  font-size: 1.125rem;
  line-height: 1.8;
}

.article-content h2 {
  margin-top: var(--spacing-xl);
  margin-bottom: var(--spacing-md);
}

.article-content h3 {
  margin-top: var(--spacing-lg);
  margin-bottom: var(--spacing-sm);
}

.article-content p {
  margin-bottom: var(--spacing-md);
  color: var(--text-secondary);
}

.article-content ul,
.article-content ol {
  margin-bottom: var(--spacing-md);
  padding-left: var(--spacing-lg);
}

.article-content li {
  margin-bottom: var(--spacing-xs);
  color: var(--text-secondary);
}

/* === CTA Block === */
.cta-block {
  background: linear-gradient(135deg, rgba(102, 126, 234, 0.08) 0%, rgba(118, 75, 162, 0.08) 100%);
  border: 2px solid rgba(102, 126, 234, 0.2);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  margin: var(--spacing-xl) 0;
  text-align: center;
}

.cta-block h3 {
  color: var(--text-primary);
  margin-bottom: var(--spacing-sm);
}

.cta-block p {
  color: var(--text-secondary);
  margin-bottom: var(--spacing-md);
}

/* === Related Articles === */
.related-articles {
  margin-top: var(--spacing-2xl);
  padding-top: var(--spacing-xl);
  border-top: 2px solid var(--border-color);
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--spacing-lg);
  margin-top: var(--spacing-lg);
}

/* === From Blog Section (Homepage) === */
.from-blog {
  padding: var(--spacing-2xl) 0;
  background: var(--bg-primary);
}

.section-header {
  text-align: center;
  margin-bottom: var(--spacing-xl);
}

.section-header h2 {
  margin-bottom: var(--spacing-sm);
}

.section-header p {
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* === Responsive === */
@media (max-width: 768px) {
  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.5rem;
  }

  .header-container {
    padding: var(--spacing-sm) var(--spacing-md);
  }

  .nav-menu {
    position: fixed;
    top: 60px;
    left: 0;
    right: 0;
    background: white;
    flex-direction: column;
    gap: 0;
    padding: var(--spacing-sm) 0;
    box-shadow: var(--shadow-lg);
    transform: translateY(-150%);
    transition: transform var(--transition-normal);
    z-index: 1000;
  }

  .nav-menu li {
    list-style: none;
    margin: 0;
    padding: 0;
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
  }

  .nav-menu li:last-child {
    border-bottom: none;
  }

  .nav-menu a {
    display: block;
    padding: var(--spacing-md);
    color: var(--text-primary);
    font-weight: 500;
    text-decoration: none;
    border-radius: 0;
    background: transparent;
    transition: background-color var(--transition-fast);
  }

  .nav-menu a:hover,
  .nav-menu a.active {
    background: rgba(102, 126, 234, 0.08);
    color: var(--primary-color);
  }

  .nav-menu.active {
    transform: translateY(0);
  }

  .menu-toggle {
    display: flex;
  }

  .hero {
    padding: var(--spacing-xl) 0;
  }

  .calculator-card {
    margin-top: -2rem;
    padding: var(--spacing-lg);
  }

  .footer-container {
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
  }

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

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

  .input-group {
    grid-template-columns: 1fr;
  }

  .article-content {
    font-size: 1rem;
  }
}

/* === Utilities === */
.hidden {
  display: none !important;
}

.text-center {
  text-align: center;
}

.mt-lg {
  margin-top: var(--spacing-lg);
}

.mb-lg {
  margin-bottom: var(--spacing-lg);
}