@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&display=swap');

:root {
    /* Colors */
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --primary-light: #eff6ff;
    --primary-glow: rgba(37, 99, 235, 0.2);
    
    --slate-50: #f8fafc;
    --slate-100: #f1f5f9;
    --slate-200: #e2e8f0;
    --slate-400: #94a3b8;
    --slate-500: #64748b;
    --slate-600: #475569;
    --slate-900: #0f172a;
    --slate-950: #020617;
    
    --emerald-500: #10b981;
    --emerald-600: #059669;
    
    --white: #ffffff;
    
    /* Spacing */
    --container-width: 1200px;
    --header-height: 80px;
    
    /* Transitions */
    --transition-base: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--slate-50);
    color: var(--slate-900);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Layout Utilities */
.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 1.5rem;
}

.section {
    padding: 6rem 0;
}

.grid {
    display: grid;
    gap: 2rem;
}

@media (min-width: 768px) {
    .grid-2 { grid-template-columns: repeat(2, 1fr); }
    .grid-3 { grid-template-columns: repeat(3, 1fr); }
    .grid-4 { grid-template-columns: repeat(4, 1fr); }
    .grid-5 { grid-template-columns: repeat(5, 1fr); }
}

/* Typography */
h1, h2, h3, h4, h5 {
    line-height: 1.1;
    letter-spacing: -0.02em;
}

.italic { font-style: italic; }

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

.text-gradient {
    background: linear-gradient(135deg, var(--primary), #3b82f6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* Components */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    border-radius: 9999px;
    font-weight: 600;
    font-size: 0.875rem;
    transition: var(--transition-base);
    cursor: pointer;
    border: none;
    text-decoration: none;
    gap: 0.5rem;
}

.btn-primary {
    background-color: var(--primary);
    color: var(--white);
    box-shadow: 0 10px 15px -3px var(--primary-glow);
}

.btn-primary:hover {
    background-color: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 20px 25px -5px var(--primary-glow);
}

.btn-outline {
    background: transparent;
    border: 1px solid var(--slate-200);
    color: var(--slate-600);
}

.btn-outline:hover {
    background-color: var(--slate-100);
    border-color: var(--slate-400);
}

.btn-large {
    padding: 1rem 2.5rem;
    font-size: 1.125rem;
}

/* Header */
header {
    position: fixed;
    top: 0;
    width: 100%;
    height: var(--header-height);
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(12px);
    z-index: 1000;
    border-bottom: 1px solid var(--slate-200);
    display: flex;
    align-items: center;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 800;
    font-size: 1.25rem;
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: var(--primary);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
}

.nav-links {
    display: none;
}

@media (min-width: 1024px) {
    .nav-links {
        display: flex;
        gap: 2rem;
    }
    
    .nav-links a {
        text-decoration: none;
        color: var(--slate-900);
        font-weight: 500;
        font-size: 0.875rem;
        transition: var(--transition-base);
    }
    
    .nav-links a:hover {
        color: var(--primary);
    }
}

/* Hero */
.hero {
    padding-top: calc(var(--header-height) + 4rem);
    padding-bottom: 6rem;
    background: white;
}

.hero-content h1 {
    font-size: clamp(2.5rem, 5vw, 4.5rem);
    margin-bottom: 2rem;
}

.hero-desc {
    font-size: 1.25rem;
    color: var(--slate-600);
    max-width: 600px;
    margin-bottom: 2rem;
}

.expert-avatars {
    display: flex;
    align-items: center;
    margin-top: 1rem;
}

.avatar-group {
    display: flex;
    margin-right: 1rem;
}

.avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 2px solid white;
    margin-left: -0.75rem;
    object-fit: cover;
}

.avatar:first-child {
    margin-left: 0;
}

/* Cards */
.card {
    background: var(--slate-50);
    border: 1px solid transparent;
    padding: 2.5rem;
    border-radius: 2rem;
    transition: var(--transition-base);
}

.card:hover {
    background: white;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.05);
    border-color: var(--slate-100);
    transform: translateY(-5px);
}

/* Mobile Menu */
.mobile-menu-btn {
    display: block;
}

@media (min-width: 1024px) {
    .mobile-menu-btn { display: none; }
}

#mobile-menu {
    position: fixed;
    top: var(--header-height);
    left: 0;
    width: 100%;
    background: white;
    padding: 2rem;
    display: none;
    flex-direction: column;
    gap: 1.5rem;
    z-index: 999;
}

#mobile-menu.active {
    display: flex;
}

/* Pricing Switcher */
.pricing-tabs {
    display: inline-flex;
    background: var(--slate-100);
    padding: 0.375rem;
    border-radius: 9999px;
    margin-bottom: 3rem;
}

.pricing-tab {
    padding: 0.625rem 2rem;
    border-radius: 9999px;
    font-weight: 700;
    font-size: 0.875rem;
    cursor: pointer;
    transition: var(--transition-base);
    border: none;
    background: transparent;
}

.pricing-tab.active {
    background: white;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

/* Dark Section */
.bg-dark {
    background-color: var(--slate-950);
    color: white;
}

.text-slate-400 { color: var(--slate-400); }

/* FAQ */
details {
    background: white;
    border-radius: 1.5rem;
    padding: 1.5rem;
    border: 1px solid var(--slate-200);
    margin-bottom: 1rem;
    cursor: pointer;
}

summary {
    list-style: none;
    font-weight: 700;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

summary::-webkit-details-marker {
    display: none;
}