/* ===================================
   SYMLET - MAIN STYLESHEET
   Professional engineering tools
   =================================== */

:root {
    /* Colors */
    --color-background: #fafbfd;
    --color-surface: #f0f4f8;
    --color-surface-elevated: #ffffff;
    --color-border: #d4dce6;
    --color-border-hover: #b8c5d6;
    
    --color-text-primary: #0a2540;
    --color-text-secondary: #425466;
    --color-text-tertiary: #697386;
    
    --color-primary: #635bff;
    --color-primary-hover: #5046e5;
    --color-primary-light: #f0efff;
    --color-primary-gradient: linear-gradient(135deg, #635bff 0%, #7c74ff 100%);
    
    --color-success: #00d4aa;
    --color-success-hover: #00b894;
    --color-success-light: #e0f9f4;
    --color-success-gradient: linear-gradient(135deg, #00d4aa 0%, #00e6b8 100%);
    
    --color-accent: #ff6b6b;
    --color-accent-light: #fff0f0;
    --color-accent-gradient: linear-gradient(135deg, #ff6b6b 0%, #ff8787 100%);
    
    --color-orange: #ff9f43;
    --color-orange-light: #fff4e8;
    
    --color-blue: #4d9fff;
    --color-blue-light: #e8f4ff;
    
    /* Gradients */
    --gradient-warm: linear-gradient(135deg, #fff0e8 0%, #f0f4ff 50%, #e8f9f5 100%);
    --gradient-cool: linear-gradient(135deg, #e8f4ff 0%, #f0efff 100%);
    --gradient-hero: linear-gradient(180deg, #fafbfd 0%, #f0f4ff 50%, #e8f9f5 100%);
    
    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(50, 50, 93, 0.05), 0 1px 0 rgba(0, 0, 0, 0.02);
    --shadow-md: 0 4px 6px rgba(50, 50, 93, 0.11), 0 1px 3px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 13px 27px -5px rgba(50, 50, 93, 0.25), 0 8px 16px -8px rgba(0, 0, 0, 0.3);
    --shadow-xl: 0 30px 60px -12px rgba(50, 50, 93, 0.25), 0 18px 36px -18px rgba(0, 0, 0, 0.3);
    --shadow-color: 0 8px 24px rgba(99, 91, 255, 0.15);
    
    /* Spacing */
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 1.5rem;
    --space-lg: 2rem;
    --space-xl: 3rem;
    --space-2xl: 4rem;
    --space-3xl: 6rem;
    
    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 2rem;
    --font-size-4xl: 2.5rem;
    --font-size-5xl: 3rem;
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 6px;
    --radius-lg: 8px;
    --radius-xl: 12px;
    
    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 300ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===================================
   RESET & BASE
   =================================== */

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--color-text-primary);
    background: var(--color-background);
}

img {
    max-width: 100%;
    height: auto;
}

a {
    color: inherit;
    text-decoration: none;
}

/* ===================================
   TYPOGRAPHY
   =================================== */

h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    letter-spacing: -0.02em;
}

h1 { font-size: var(--font-size-5xl); }
h2 { font-size: var(--font-size-4xl); }
h3 { font-size: var(--font-size-3xl); }
h4 { font-size: var(--font-size-2xl); }
h5 { font-size: var(--font-size-xl); }
h6 { font-size: var(--font-size-lg); }

/* ===================================
   LAYOUT
   =================================== */

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

.section-header {
    text-align: center;
    max-width: 720px;
    margin: 0 auto var(--space-3xl);
}

.section-header h2 {
    margin-bottom: var(--space-md);
}

.section-header p {
    font-size: var(--font-size-lg);
    color: var(--color-text-secondary);
}

/* ===================================
   NAVIGATION
   =================================== */

.nav {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border);
    box-shadow: 0 1px 3px rgba(99, 91, 255, 0.05);
}

.nav-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-left {
    display: flex;
    align-items: center;
    gap: var(--space-xl);
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--color-text-primary);
}

.brand-icon {
    width: 24px;
    height: 24px;
    color: var(--color-primary);
}

.nav-links {
    display: flex;
    gap: var(--space-lg);
}

.nav-links a {
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
    font-weight: 500;
    transition: color var(--transition-fast);
}

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

.nav-right {
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.nav-link {
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
    font-weight: 500;
    transition: color var(--transition-fast);
}

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

/* ===================================
   BUTTONS
   =================================== */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.625rem 1.25rem;
    font-size: var(--font-size-sm);
    font-weight: 500;
    border-radius: var(--radius-md);
    border: 1px solid transparent;
    cursor: pointer;
    transition: all var(--transition-base);
    text-decoration: none;
}

.btn-primary {
    background: var(--color-primary-gradient);
    color: white;
    box-shadow: 0 4px 12px rgba(99, 91, 255, 0.2);
}

.btn-primary:hover {
    background: var(--color-primary-hover);
    box-shadow: 0 6px 20px rgba(99, 91, 255, 0.35);
    transform: translateY(-2px);
}

.btn-secondary {
    background: white;
    color: var(--color-text-primary);
    border-color: var(--color-border);
    box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
    border-color: var(--color-border-hover);
    box-shadow: var(--shadow-md);
    transform: translateY(-1px);
}

.btn-large {
    padding: 0.875rem 1.75rem;
    font-size: var(--font-size-base);
}

/* ===================================
   BADGES
   =================================== */

.badge {
    display: inline-flex;
    align-items: center;
    padding: 0.25rem 0.625rem;
    font-size: var(--font-size-xs);
    font-weight: 600;
    border-radius: var(--radius-sm);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.badge-free {
    background: var(--color-success-light);
    color: var(--color-success);
}

.badge-pro {
    background: var(--color-primary-light);
    color: var(--color-primary);
}

/* ===================================
   FOOTER
   =================================== */

.footer {
    background: var(--gradient-cool);
    border-top: 1px solid var(--color-border);
    padding: var(--space-3xl) 0 var(--space-xl);
    margin-top: var(--space-3xl);
    position: relative;
}

.footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent 0%, var(--color-primary) 50%, transparent 100%);
    opacity: 0.3;
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: var(--space-2xl);
    margin-bottom: var(--space-2xl);
}

.footer-brand {
    max-width: 320px;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    font-size: var(--font-size-xl);
    font-weight: 600;
    margin-bottom: var(--space-md);
}

.footer-brand p {
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
    margin-bottom: var(--space-md);
}

.footer-wavelet {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    margin-top: var(--space-lg);
}

.footer-wavelet span {
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.footer-wavelet-logo {
    height: 24px;
    opacity: 0.8;
}

.footer-links h4 {
    font-size: var(--font-size-sm);
    font-weight: 600;
    margin-bottom: var(--space-md);
    color: var(--color-text-primary);
}

.footer-links {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.footer-links a {
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
    transition: color var(--transition-fast);
}

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

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: var(--space-lg);
    border-top: 1px solid var(--color-border);
}

.footer-legal {
    display: flex;
    gap: var(--space-lg);
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
}

.footer-legal a {
    color: var(--color-text-tertiary);
    transition: color var(--transition-fast);
}

.footer-legal a:hover {
    color: var(--color-text-primary);
}

.footer-social {
    display: flex;
    gap: var(--space-md);
}

.footer-social a {
    color: var(--color-text-tertiary);
    font-size: var(--font-size-sm);
    transition: color var(--transition-fast);
}

.footer-social a:hover {
    color: var(--color-text-primary);
}

/* ===================================
   RESPONSIVE
   =================================== */

@media (max-width: 1024px) {
    .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: var(--space-xl);
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .nav-container {
        padding: 0 var(--space-md);
    }
    
    .container {
        padding: 0 var(--space-md);
    }
    
    h1 { font-size: var(--font-size-4xl); }
    h2 { font-size: var(--font-size-3xl); }
    
    .footer-grid {
        grid-template-columns: 1fr;
        gap: var(--space-xl);
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: var(--space-md);
        text-align: center;
    }
}