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

:root {
    /* Premium Color Palette - Technical/Industrial */
    --color-primary: #0f1419;
    --color-secondary: #1e3a5f;
    --color-accent: #3b82f6;
    --color-accent-dark: #2563eb;
    --color-text: #1a2332;
    --color-text-muted: #64748b;
    --color-bg: #ffffff;
    --color-bg-alt: #f8fafc;
    --color-border: #e2e8f0;
    
    /* Typography */
    --font-display: 'Space Grotesk', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    
    /* Spacing Scale */
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 2rem;
    --space-lg: 4rem;
    --space-xl: 6rem;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 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);
    
    /* Transitions */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: var(--font-body);
    font-size: 1rem;
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-display);
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 1rem;
    color: var(--color-primary);
}

h1 { font-size: clamp(2.5rem, 5vw, 4rem); }
h2 { font-size: clamp(2rem, 4vw, 3rem); }
h3 { font-size: clamp(1.5rem, 3vw, 2rem); }
h4 { font-size: 1.5rem; }
h5 { font-size: 1.25rem; }
h6 { font-size: 1rem; }

p {
    margin-bottom: 1rem;
    line-height: 1.7;
}

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

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

/* Utility Classes */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 var(--space-md);
}

.section-padding {
    padding: var(--space-xl) 0;
}

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

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

.section-header {
    text-align: center;
    max-width: 800px;
    margin: 0 auto var(--space-lg);
}

.section-label {
    display: inline-block;
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-accent);
    margin-bottom: var(--space-sm);
}

.section-title {
    font-size: clamp(2rem, 4vw, 3rem);
    margin-bottom: var(--space-sm);
}

.section-subtitle {
    font-size: 1.125rem;
    color: var(--color-text-muted);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 1rem 2rem;
    font-family: var(--font-display);
    font-size: 1rem;
    font-weight: 600;
    text-align: center;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
}

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

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

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

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

.btn-lg {
    padding: 1.25rem 2.5rem;
    font-size: 1.125rem;
}

.alert-success { background: #d4edda; }
.alert-error { background: #f8d7da; }

/* Responsive */
@media (max-width: 768px) {
    :root {
        --space-lg: 3rem;
        --space-xl: 4rem;
    }
    
    .container {
        padding: 0 var(--space-sm);
    }
    
    .section-padding {
        padding: var(--space-lg) 0;
    }
}

@media (max-width: 480px) {
    :root {
        --space-sm: 0.875rem;
        --space-lg: 2.5rem;
        --space-xl: 3.5rem;
    }
    
    .container {
        padding: 0 1rem;
    }
    
    .section-padding {
        padding: 2.5rem 0;
    }
    
    .section-header {
        margin-bottom: 2rem;
    }
    
    .btn {
        padding: 0.875rem 1.75rem;
        font-size: 0.9375rem;
    }
    
    .btn-lg {
        padding: 1rem 2rem;
        font-size: 1rem;
    }
}