/* Opus Website Styles
   Clean, minimal, professional - designed for academics
*/

:root {
  --color-primary: #1e3a5f;
  --color-primary-light: #2d5a8b;
  --color-accent: #4a7c59;
  --color-accent-light: #5d9a6d;
  --color-text: #2c3e50;
  --color-text-light: #5a6c7d;
  --color-bg: #ffffff;
  --color-bg-alt: #f8f9fa;
  --color-border: #e1e5e9;
  --font-heading: 'Source Sans Pro', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-body: 'Source Serif Pro', Georgia, 'Times New Roman', serif;
  --font-mono: 'Source Code Pro', 'Fira Code', monospace;
  --max-width: 1200px;
  --max-width-narrow: 800px;
}

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

html {
  font-size: 18px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.7;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 600;
  line-height: 1.3;
  color: var(--color-primary);
}

h1 { font-size: 2.5rem; margin-bottom: 1rem; }
h2 { font-size: 1.8rem; margin-bottom: 0.75rem; }
h3 { font-size: 1.4rem; margin-bottom: 0.5rem; }

p {
  margin-bottom: 1rem;
}

a {
  color: var(--color-primary-light);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--color-accent);
}

/* Header & Navigation */
header {
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
}

nav {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-primary);
  text-decoration: none;
}

.logo span {
  color: var(--color-accent);
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
  align-items: center;
}

.nav-links a {
  font-family: var(--font-heading);
  font-size: 0.95rem;
  color: var(--color-text);
  padding: 0.5rem 0;
  border-bottom: 2px solid transparent;
  transition: all 0.2s ease;
}

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

.nav-links .btn-login {
  color: var(--color-primary);
  border: 1px solid var(--color-primary);
  padding: 0.5rem 1.25rem;
  border-radius: 4px;
}

.nav-links .btn-login:hover {
  background: var(--color-primary);
  color: white;
  border-bottom-color: transparent;
}

/* Buttons */
.btn {
  display: inline-block;
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 600;
  padding: 0.75rem 1.75rem;
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.2s ease;
  text-decoration: none;
  border: none;
}

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

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

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

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

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

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

/* Hero Section */
.hero {
  padding: 5rem 2rem;
  text-align: center;
  background: linear-gradient(180deg, var(--color-bg-alt) 0%, var(--color-bg) 100%);
}

.hero-content {
  max-width: var(--max-width-narrow);
  margin: 0 auto;
}

.hero h1 {
  font-size: 3rem;
  margin-bottom: 1.5rem;
}

.hero .tagline {
  font-size: 1.3rem;
  color: var(--color-text-light);
  margin-bottom: 2rem;
}

.hero-buttons {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

/* Sections */
section {
  padding: 4rem 2rem;
}

.section-header {
  text-align: center;
  max-width: var(--max-width-narrow);
  margin: 0 auto 3rem;
}

.section-header p {
  color: var(--color-text-light);
  font-size: 1.1rem;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
}

.container-narrow {
  max-width: var(--max-width-narrow);
  margin: 0 auto;
}

.bg-alt {
  background: var(--color-bg-alt);
}

/* Features Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  max-width: var(--max-width);
  margin: 0 auto;
}

.feature-card {
  background: var(--color-bg);
  padding: 2rem;
  border-radius: 8px;
  border: 1px solid var(--color-border);
  transition: box-shadow 0.2s ease;
}

.feature-card:hover {
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.feature-card h3 {
  margin-bottom: 0.75rem;
}

.feature-card p {
  color: var(--color-text-light);
  margin-bottom: 0;
}

.feature-icon {
  font-size: 2rem;
  margin-bottom: 1rem;
}

/* Comparison Table */
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  margin: 2rem 0;
  font-family: var(--font-heading);
  font-size: 0.95rem;
}

.comparison-table th,
.comparison-table td {
  padding: 1rem;
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}

.comparison-table th {
  background: var(--color-bg-alt);
  font-weight: 600;
  color: var(--color-primary);
}

.comparison-table tr:hover td {
  background: var(--color-bg-alt);
}

.check {
  color: var(--color-accent);
  font-weight: bold;
}

.cross {
  color: #b0b0b0;
}

/* Pricing */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
  max-width: var(--max-width);
  margin: 0 auto;
}

.pricing-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 2.5rem 2rem;
  text-align: center;
  position: relative;
  transition: box-shadow 0.2s ease;
}

.pricing-card:hover {
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.1);
}

.pricing-card.featured {
  border-color: var(--color-primary);
  border-width: 2px;
}

.pricing-card.featured::before {
  content: 'Most Popular';
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--color-primary);
  color: white;
  font-family: var(--font-heading);
  font-size: 0.8rem;
  font-weight: 600;
  padding: 0.25rem 1rem;
  border-radius: 4px;
}

.pricing-card h3 {
  margin-bottom: 0.5rem;
}

.pricing-card .price {
  font-family: var(--font-heading);
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--color-primary);
  margin: 1rem 0;
}

.pricing-card .price span {
  font-size: 1rem;
  font-weight: 400;
  color: var(--color-text-light);
}

.pricing-card .description {
  color: var(--color-text-light);
  margin-bottom: 1.5rem;
}

.pricing-card ul {
  list-style: none;
  text-align: left;
  margin-bottom: 2rem;
}

.pricing-card li {
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--color-border);
  font-family: var(--font-heading);
  font-size: 0.95rem;
}

.pricing-card li:last-child {
  border-bottom: none;
}

.pricing-card li::before {
  content: '✓';
  color: var(--color-accent);
  margin-right: 0.5rem;
  font-weight: bold;
}

/* Help / Documentation */
.help-nav {
  background: var(--color-bg-alt);
  border-bottom: 1px solid var(--color-border);
  padding: 1rem 2rem;
}

.help-nav ul {
  list-style: none;
  display: flex;
  gap: 2rem;
  max-width: var(--max-width);
  margin: 0 auto;
  flex-wrap: wrap;
}

.help-nav a {
  font-family: var(--font-heading);
  font-size: 0.9rem;
  color: var(--color-text-light);
  padding: 0.5rem 0;
  border-bottom: 2px solid transparent;
}

.help-nav a:hover,
.help-nav a.active {
  color: var(--color-primary);
  border-bottom-color: var(--color-accent);
}

.help-content {
  display: grid;
  grid-template-columns: 250px 1fr;
  gap: 3rem;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 3rem 2rem;
}

.help-sidebar {
  position: sticky;
  top: 100px;
  align-self: start;
}

.help-sidebar h4 {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-light);
  margin-bottom: 1rem;
}

.help-sidebar ul {
  list-style: none;
}

.help-sidebar li {
  margin-bottom: 0.5rem;
}

.help-sidebar a {
  font-family: var(--font-heading);
  font-size: 0.95rem;
  color: var(--color-text);
  display: block;
  padding: 0.25rem 0;
}

.help-sidebar a:hover {
  color: var(--color-primary);
}

.help-article {
  max-width: 100%;
}

.help-article h1 {
  margin-bottom: 0.5rem;
}

.help-article .last-updated {
  color: var(--color-text-light);
  font-size: 0.9rem;
  margin-bottom: 2rem;
}

.help-article h2 {
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-border);
}

.help-article h2:first-of-type {
  margin-top: 0;
  padding-top: 0;
  border-top: none;
}

.help-article code {
  font-family: var(--font-mono);
  background: var(--color-bg-alt);
  padding: 0.15rem 0.4rem;
  border-radius: 3px;
  font-size: 0.9em;
}

.help-article pre {
  background: var(--color-bg-alt);
  padding: 1.5rem;
  border-radius: 6px;
  overflow-x: auto;
  margin: 1.5rem 0;
}

.help-article pre code {
  background: none;
  padding: 0;
}

.help-article ul, .help-article ol {
  margin: 1rem 0 1rem 1.5rem;
}

.help-article li {
  margin-bottom: 0.5rem;
}

.help-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.help-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 1.5rem;
  transition: all 0.2s ease;
}

.help-card:hover {
  border-color: var(--color-primary-light);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.help-card h3 {
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
}

.help-card p {
  color: var(--color-text-light);
  font-size: 0.95rem;
  margin-bottom: 0;
}

/* About Page */
.about-hero {
  padding: 4rem 2rem;
  background: var(--color-bg-alt);
  text-align: center;
}

.about-hero h1 {
  margin-bottom: 1rem;
}

.about-hero p {
  max-width: 600px;
  margin: 0 auto;
  color: var(--color-text-light);
  font-size: 1.2rem;
}

.values-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
}

.value-item h3 {
  margin-bottom: 0.5rem;
}

.value-item p {
  color: var(--color-text-light);
}

/* Footer */
footer {
  background: var(--color-primary);
  color: rgba(255, 255, 255, 0.8);
  padding: 4rem 2rem 2rem;
  margin-top: 4rem;
}

.footer-content {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 3rem;
}

.footer-section h4 {
  color: white;
  font-family: var(--font-heading);
  font-size: 1rem;
  margin-bottom: 1rem;
}

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

.footer-section li {
  margin-bottom: 0.5rem;
}

.footer-section a {
  color: rgba(255, 255, 255, 0.7);
  font-family: var(--font-heading);
  font-size: 0.9rem;
}

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

.footer-bottom {
  max-width: var(--max-width);
  margin: 3rem auto 0;
  padding-top: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  text-align: center;
  font-family: var(--font-heading);
  font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 768px) {
  html {
    font-size: 16px;
  }

  .hero h1 {
    font-size: 2.2rem;
  }

  nav {
    flex-direction: column;
    gap: 1rem;
  }

  .nav-links {
    flex-wrap: wrap;
    justify-content: center;
  }

  .help-content {
    grid-template-columns: 1fr;
  }

  .help-sidebar {
    position: static;
    border-bottom: 1px solid var(--color-border);
    padding-bottom: 1.5rem;
    margin-bottom: 1.5rem;
  }

  .help-sidebar ul {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem 1.5rem;
  }
}

/* Utilities */
.text-center { text-align: center; }
.mt-2 { margin-top: 2rem; }
.mb-2 { margin-bottom: 2rem; }
.mt-3 { margin-top: 3rem; }
.mb-3 { margin-bottom: 3rem; }