:root {
    --primary: #3f51b5;
    --primary-dark: #303f9f;
    --secondary: #ff5722;
    --dark: #212121;
    --light: #f5f5f5;
    --gray: #757575;
    --success: #4caf50;
    --warning: #ff9800;
    --error: #f44336;
    --border-radius: 10px;
    --shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
    --card-bg: #ffffff;
    --body-bg: #f9f9f9;
}



* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.main-container {
    background-color: var(--body-bg);
    color: var(--dark);
    line-height: 1.6;
    min-height: 100vh;
    padding: 20px;
    transition: var(--transition);
    width: 100%;
}

.container {
    width: 100%;
    margin: 0 auto;
}

.header-title {
    text-align: center;
    padding: 30px 20px;
    position: relative;
}

h1 {
    font-size: 2.8rem;
    margin-bottom: 15px;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    font-weight: 800;
}

.subtitle {
    font-size: 1.2rem;
    color: var(--gray);
    max-width: 700px;
    margin: 0 auto 30px;
}



.main-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin-bottom: 40px;
}

@media (max-width: 900px) {
    .main-content {
        grid-template-columns: 1fr;
    }
}

.data-input {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 30px;
    transition: var(--transition);
}

.input-group {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: var(--primary);
}

textarea, input {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid #ddd;
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
    background-color: var(--card-bg);
    color: var(--dark);
}

textarea {
    min-height: 150px;
    resize: vertical;
}

textarea:focus, input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(63, 81, 181, 0.2);
}

.buttons {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

button {
    background: var(--primary);
    color: white;
    border: none;
    padding: 12px 20px;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-weight: 600;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    
}

button:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
}

button.secondary {
    background: var(--secondary);
}

button.secondary:hover {
    background: #e64a19;
}

button i {
    margin-right: 8px;
}

.results {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 30px;
    transition: var(--transition);
}

.metrics-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 30px;
}

@media (max-width: 600px) {
    .metrics-grid {
        grid-template-columns: 1fr;
    }
}

.metric-card {
    background: rgba(63, 81, 181, 0.1);
    border-radius: var(--border-radius);
    padding: 20px;
    border-left: 4px solid var(--primary);
    transition: var(--transition);
}

.metric-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.metric-title {
    font-size: 1rem;
    color: var(--primary);
    margin-bottom: 10px;
    font-weight: 600;
    display: flex;
    align-items: center;
}

.metric-title i {
    margin-right: 10px;
}

.metric-value {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--dark);
}

.metric-description {
    font-size: 0.9rem;
    color: var(--gray);
    margin-top: 5px;
}

.chart-container {
    margin-top: 30px;
    height: 300px;
}

.examples {
    margin-top: 30px;
}

.examples h3 {
    margin-bottom: 15px;
    color: var(--primary);
}

.example-buttons {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.example-btn {
    background: rgba(63, 81, 181, 0.1);
    color: var(--primary);
    border: none;
    padding: 8px 15px;
    border-radius: 20px;
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.9rem;
}

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

.explanation {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 30px;
    margin-top: 30px;
    transition: var(--transition);
}

.explanation h2 {
    color: var(--primary);
    margin-bottom: 20px;
}

.concept {
    margin-bottom: 25px;
}

.concept h3 {
    color: var(--secondary);
    margin-bottom: 10px;
    display: flex;
    align-items: center;
}

.concept h3 i {
    margin-right: 10px;
}

.concept p {
    margin-bottom: 10px;
    color: var(--dark);
}

.concept-formula {
    background: rgba(255, 87, 34, 0.1);
    padding: 15px;
    border-radius: var(--border-radius);
    font-family: 'Courier New', monospace;
    margin: 10px 0;
    color: var(--secondary);
    border-left: 4px solid var(--secondary);
}

.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 25px;
    margin: 40px 0;
}

.feature-card {
    background: var(--card-bg);
    padding: 25px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-5px);
}

.feature-card i {
    font-size: 2.5rem;
    color: var(--primary);
    margin-bottom: 15px;
}

.feature-card h3 {
    margin-bottom: 10px;
    color: var(--dark);
}

.feature-card p {
    color: var(--gray);
}



.notification {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 15px 25px;
    background: var(--success);
    color: white;
    border-radius: var(--border-radius);
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    transform: translateX(150%);
    transition: transform 0.3s ease;
    z-index: 1000;
}

.notification.show {
    transform: translateX(0);
}

.notification.error {
    background: var(--error);
}

.notification.warning {
    background: var(--warning);
}

@media (max-width: 600px) {
    h1 {
        font-size: 2.2rem;
    }
    
    .data-input, .results, .explanation {
        padding: 20px;
    }
}


/* ===== ARTICLE SPECIFIC STYLES - NO BODY STYLES ===== */
#stats-guide-article {
      width: 95%;
      margin: 0 auto;
      padding: 2rem 1.5rem 3rem 1.5rem;
      font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    }

    /* Hero Section */
    .stats-guide-hero {
      text-align: center;
      margin-bottom: 2.5rem;
      padding: 2rem 1.5rem;
      background: linear-gradient(135deg, #3f51b5 0%, #ff5722 100%);
      border-radius: 32px;
      box-shadow: 0 12px 30px rgba(63, 81, 181, 0.3);
    }

    .stats-guide-hero h2 {
      font-size: 2.6rem;
      font-weight: 800;
      color: white;
      margin-bottom: 1rem;
      letter-spacing: -0.02em;
      font-family: 'Montserrat', serif;
    }

    .stats-guide-hero .stats-hero-sub {
      font-size: 1.2rem;
      color: rgba(255, 255, 255, 0.9);
      max-width: 720px;
      margin: 0 auto;
      line-height: 1.5;
    }

    .stats-guide-meta {
      display: flex;
      justify-content: center;
      gap: 2rem;
      color: rgba(255, 255, 255, 0.8);
      font-weight: 500;
      margin-top: 1.2rem;
      flex-wrap: wrap;
    }

    .stats-guide-meta span i {
      margin-right: 0.5rem;
    }

    /* Main Content */
    .stats-main-content {
      background: white;
      border-radius: 28px;
      padding: 2rem 2rem 2.5rem 2rem;
      box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
      border: 1px solid rgba(63, 81, 181, 0.15);
    }

    .stats-main-content h2 {
      font-size: 1.8rem;
      font-weight: 700;
      margin-top: 2rem;
      margin-bottom: 1rem;
      color: #3f51b5;
      border-left: 5px solid #ff5722;
      padding-left: 1rem;
      font-family: 'Montserrat', serif;
    }

    .stats-main-content h2:first-of-type {
      margin-top: 0;
    }

    .stats-main-content h3 {
      font-size: 1.35rem;
      font-weight: 600;
      margin: 1.5rem 0 0.75rem 0;
      color: #ff5722;
    }

    .stats-main-content p {
      font-size: 1.05rem;
      color: #2d3748;
      margin-bottom: 1.2rem;
      line-height: 1.6;
    }

    .stats-main-content ul, .stats-main-content ol {
      margin: 1rem 0 1.2rem 1.8rem;
      color: #2d3748;
      line-height: 1.6;
    }

    .stats-main-content li {
      margin-bottom: 0.5rem;
    }

    .stats-highlight-box {
      background: linear-gradient(135deg, rgba(63, 81, 181, 0.08), rgba(255, 87, 34, 0.05));
      border-left: 6px solid #ff5722;
      padding: 1.25rem 1.5rem;
      border-radius: 20px;
      margin: 1.75rem 0;
    }

    .stats-formula-box {
      background: rgba(63, 81, 181, 0.1);
      border-radius: 16px;
      padding: 1rem 1.5rem;
      margin: 1rem 0;
      font-family: 'Courier New', monospace;
      font-size: 1.1rem;
      text-align: center;
      border: 1px dashed #3f51b5;
    }

    .stats-pro-tip {
      background: rgba(255, 87, 34, 0.1);
      border-radius: 20px;
      padding: 1.2rem 1.5rem;
      margin: 1.5rem 0;
      display: flex;
      gap: 1rem;
      align-items: flex-start;
      border: 1px solid rgba(63, 81, 181, 0.3);
    }

    .stats-pro-tip i {
      font-size: 1.8rem;
      color: #ff5722;
    }

    .stats-stats-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
      gap: 1.2rem;
      margin: 2rem 0;
    }

    .stats-stat-card {
      background: #f5f5f5;
      border-radius: 20px;
      padding: 1.2rem;
      text-align: center;
      transition: all 0.2s;
      border: 1px solid rgba(63, 81, 181, 0.2);
    }

    .stats-stat-card .stat-icon {
      font-size: 2rem;
      margin-bottom: 0.5rem;
    }

    .stats-quote-block {
      background: #f5f5f5;
      padding: 1.5rem;
      border-radius: 24px;
      text-align: center;
      font-style: italic;
      margin: 1.5rem 0;
      border: 1px solid rgba(63, 81, 181, 0.2);
    }

    .stats-quote-block i {
      font-size: 2rem;
      color: #ff5722;
      margin-bottom: 0.5rem;
      display: inline-block;
    }

    .stats-table-wrapper {
      overflow-x: auto;
      margin: 1.5rem 0;
    }

    .stats-examples-table {
      width: 100%;
      border-collapse: collapse;
      background: #f5f5f5;
      border-radius: 16px;
      overflow: hidden;
    }

    .stats-examples-table th, .stats-examples-table td {
      padding: 12px 16px;
      text-align: left;
      border-bottom: 1px solid rgba(63, 81, 181, 0.2);
    }

    .stats-examples-table th {
      background: rgba(63, 81, 181, 0.1);
      font-weight: 600;
      color: #3f51b5;
    }

    .stats-examples-table tr:hover {
      background: rgba(255, 87, 34, 0.05);
    }

    .stats-comparison-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 1.2rem;
      margin: 1.5rem 0;
    }

    .stats-comparison-card {
      background: #f5f5f5;
      border-radius: 16px;
      padding: 1.2rem;
      border: 1px solid rgba(63, 81, 181, 0.2);
      transition: all 0.2s;
    }

    .stats-comparison-card:hover {
      transform: translateY(-3px);
      box-shadow: 0 8px 20px rgba(63, 81, 181, 0.1);
    }

    .stats-comparison-title {
      font-weight: 700;
      color: #3f51b5;
      margin-bottom: 0.5rem;
      font-size: 1.1rem;
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }

    .stats-footer-note {
      margin-top: 2.5rem;
      text-align: center;
      font-size: 0.85rem;
      color: #718096;
      border-top: 1px solid #e2e8f0;
      padding-top: 2rem;
    }

    @media (max-width: 768px) {
      .stats-guide-hero h2 {
        font-size: 2rem;
      }
      .stats-main-content {
        padding: 1.5rem;
      }
      #stats-guide-article {
        padding: 1rem;
      }
    }