/* InvoiceGo Design System - Optimized */

:root {
    /* Brand Colors */
    --brand-primary: #001de6;
    --brand-secondary: #10b981;

    /* Blue Scale */
    --blue-500: #1E5EFF;
    --blue-600: #0033CC;
    --blue-700: #002299;

    /* Green Scale */
    --green-400: #34d399;
    --green-500: #10b981;

    /* Neutral Scale */
    --gray-50: #f8fafc;
    --gray-100: #f1f5f9;
    --gray-200: #e2e8f0;
    --gray-300: #cbd5e1;
    --gray-400: #94a3b8;
    --gray-500: #64748b;
    --gray-600: #475569;
    --gray-700: #334155;
    --gray-800: #1e293b;
    --gray-900: #0f172a;

    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-12: 3rem;
    --space-16: 4rem;

    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 5%);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 10%), 0 2px 4px -1px rgb(0 0 0 / 6%);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 10%), 0 4px 6px -2px rgb(0 0 0 / 5%);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 10%), 0 10px 10px -5px rgb(0 0 0 / 4%);

    /* Transitions */
    --ease: cubic-bezier(0.4, 0, 0.2, 1);
    --duration-fast: 150ms;
    --duration-base: 200ms;
    --duration-slow: 300ms;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Inter', 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--gray-700);
    background: #fff;
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 var(--space-6);
}

/* Header */
header {
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--gray-200);
    padding: var(--space-4) 0;
    position: sticky;
    top: 0;
    z-index: 1000;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* Logo */
.logo {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    text-decoration: none;
    transition: transform var(--duration-base) var(--ease);
}

.logo:hover { transform: translateY(-2px); }
.logo img { height: 48px; width: auto; }
.logo span { font-size: 1.5rem; font-weight: 700; color: var(--brand-primary); }

/* Navigation */
.nav-links {
    display: flex;
    gap: var(--space-12);
    list-style: none;
    align-items: center;
}

.nav-links > li { position: relative; }

.nav-links a {
    color: var(--gray-700);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.9375rem;
    transition: color var(--duration-base) var(--ease);
    padding: var(--space-2) 0;
    display: block;
}

.nav-links a:hover { color: var(--blue-500); }

/* Dropdown */
.dropdown { position: relative; }

.dropdown-toggle {
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.dropdown-toggle::after {
    content: "▼";
    font-size: 0.625rem;
    transition: transform var(--duration-base) var(--ease);
    color: var(--gray-400);
}

.dropdown:hover .dropdown-toggle::after { transform: rotate(180deg); }

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    background: #fff;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    padding: var(--space-2);
    min-width: 220px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all var(--duration-base) var(--ease);
    border: 1px solid var(--gray-200);
    margin-top: var(--space-2);
}

.dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-menu li { list-style: none; }

.dropdown-menu a {
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-sm);
    transition: all var(--duration-fast) var(--ease);
}

.dropdown-menu a:hover {
    background: var(--gray-50);
    color: var(--blue-500);
    padding-left: calc(var(--space-4) + 0.25rem);
}

/* Mobile Menu */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-2);
}

.mobile-menu-toggle span {
    width: 25px;
    height: 2px;
    background: var(--gray-700);
    border-radius: 2px;
    transition: all var(--duration-base) var(--ease);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #f8fafc 0%, #e0e7ff 50%, #dbeafe 100%);
    padding: calc(var(--space-16) * 2) 0;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -50%;
    width: 100%;
    height: 200%;
    background: radial-gradient(circle, rgba(30, 94, 255, 0.1) 0%, transparent 70%);
    pointer-events: none;
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-16);
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-text h1 {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: var(--space-6);
    color: var(--gray-900);
    background: linear-gradient(135deg, var(--gray-900), var(--blue-600));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-text p {
    font-size: 1.25rem;
    color: var(--gray-600);
    margin-bottom: var(--space-8);
    line-height: 1.7;
}

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.hero-image img {
    max-width: 50%;
    height: auto;
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-xl);
}

/* App Store Links */
.app-store-links {
    display: flex;
    gap: var(--space-4);
    margin-top: var(--space-8);
}

.app-store-links a {
    transition: transform var(--duration-base) var(--ease);
    display: block;
}

.app-store-links a:hover { transform: translateY(-4px); }
.app-store-links img { height: 56px; width: auto; }

/* Sections */
section { padding: calc(var(--space-16) * 1.5) 0; }

.section-title {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    font-weight: 700;
    text-align: center;
    margin-bottom: var(--space-12);
    color: var(--gray-900);
}

.section-header {
    text-align: center;
    margin-bottom: calc(var(--space-16) * 1.5);
}

.section-subtitle {
    font-size: 1.125rem;
    color: var(--gray-600);
    margin-top: var(--space-4);
    max-width: 600px;
    margin-inline: auto;
}

/* Features Grid */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--space-8);
    margin-top: var(--space-12);
}

.feature-card {
    background: #fff;
    padding: var(--space-8);
    border-radius: var(--radius-xl);
    border: 1px solid var(--gray-200);
    transition: all var(--duration-base) var(--ease);
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--blue-500), var(--green-500));
    transform: scaleX(0);
    transform-origin: left;
    transition: transform var(--duration-base) var(--ease);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--blue-500);
}

.feature-card:hover::before { transform: scaleX(1); }

.feature-icon { font-size: 3rem; margin-bottom: var(--space-4); }

.feature-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--space-2);
    color: var(--gray-900);
}

.feature-card p { color: var(--gray-600); line-height: 1.7; }

/* Why Choose Section */
.why-choose-section {
    background: linear-gradient(180deg, #fff 0%, var(--gray-50) 100%);
    padding: calc(var(--space-16) * 2) 0;
}

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: var(--space-8);
    margin-bottom: calc(var(--space-16) * 1.5);
}

.stat-card {
    text-align: center;
    padding: var(--space-8);
    background: #fff;
    border-radius: var(--radius-xl);
    border: 1px solid var(--gray-200);
    transition: all var(--duration-base) var(--ease);
    position: relative;
    overflow: hidden;
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--blue-500), var(--green-500));
    opacity: 0;
    transition: opacity var(--duration-base) var(--ease);
}

.stat-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--blue-500);
}

.stat-card:hover::before { opacity: 1; }

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--blue-500), var(--green-500));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: var(--space-2);
}

.stat-label {
    font-size: 0.9375rem;
    color: var(--gray-600);
    font-weight: 500;
}

/* Benefits Grid */
.benefits-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-8);
}

.benefit-card {
    background: #fff;
    padding: var(--space-8);
    border-radius: var(--radius-xl);
    border: 1px solid var(--gray-200);
    transition: all var(--duration-slow) var(--ease);
    position: relative;
}

.benefit-card::after {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: var(--radius-xl);
    padding: 2px;
    background: linear-gradient(135deg, var(--blue-500), var(--green-500));
    -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    -webkit-mask-composite: xor;
    mask-composite: exclude;
    opacity: 0;
    transition: opacity var(--duration-slow) var(--ease);
}

.benefit-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-xl);
}

.benefit-card:hover::after { opacity: 1; }

.benefit-icon {
    font-size: 2.5rem;
    margin-bottom: var(--space-4);
    display: inline-block;
    transition: transform var(--duration-slow) var(--ease);
}

.benefit-card:hover .benefit-icon { transform: scale(1.1) rotate(5deg); }

.benefit-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--space-2);
    color: var(--gray-900);
}

.benefit-card p {
    color: var(--gray-600);
    line-height: 1.7;
    font-size: 0.9375rem;
}

/* Legacy Benefits */
.benefits { background: var(--gray-50); }
.benefits-content { max-width: 900px; margin: 0 auto; }
.benefits-list { list-style: none; display: grid; gap: var(--space-4); }

.benefits-list li {
    padding-left: var(--space-8);
    position: relative;
    color: var(--gray-700);
}

.benefits-list li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--green-500);
    font-weight: bold;
}

/* Pricing Section */
.pricing { background: linear-gradient(135deg, #f8fafc 0%, #f1f5f9 100%); }

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-8);
    max-width: 1000px;
    margin: 0 auto;
}

.pricing-card {
    background: #fff;
    padding: var(--space-12);
    border-radius: var(--radius-2xl);
    border: 2px solid var(--gray-200);
    text-align: center;
    transition: all var(--duration-base) var(--ease);
}

.pricing-card:hover {
    transform: translateY(-12px);
    box-shadow: var(--shadow-xl);
    border-color: var(--blue-500);
}

.pricing-card.featured {
    border-color: var(--blue-500);
    box-shadow: var(--shadow-lg);
    transform: scale(1.05);
}

.pricing-card.featured:hover { transform: scale(1.05) translateY(-12px); }

.pricing-card h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: var(--space-2);
    color: var(--gray-900);
}

.price {
    font-size: 3rem;
    font-weight: 800;
    color: var(--blue-500);
    margin: var(--space-6) 0;
}

.price-features {
    list-style: none;
    margin: var(--space-8) 0;
    text-align: left;
}

.price-features li {
    padding: var(--space-2) 0;
    padding-left: var(--space-8);
    position: relative;
    color: var(--gray-600);
}

.price-features li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--green-500);
    font-weight: bold;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.875rem 1.75rem;
    border-radius: var(--radius-lg);
    font-weight: 600;
    text-decoration: none;
    transition: all var(--duration-base) var(--ease);
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--blue-500), var(--blue-600));
    color: #fff;
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    background: linear-gradient(135deg, var(--blue-600), var(--blue-700));
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

.btn-secondary {
    background: #fff;
    color: var(--blue-500);
    border: 2px solid var(--blue-500);
}

.btn-secondary:hover {
    background: var(--blue-500);
    color: #fff;
    transform: translateY(-2px);
}

/* CTA Section */
.cta-section {
    background: linear-gradient(135deg, var(--blue-500), var(--blue-700));
    color: #fff;
    text-align: center;
    padding: calc(var(--space-16) * 1.5) 0;
    position: relative;
    overflow: hidden;
}

.cta-section::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.1) 0%, transparent 70%);
    animation: pulse 15s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); opacity: 1; }
    50% { transform: scale(1.1); opacity: 0.8; }
}

.cta-section h2 {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    font-weight: 700;
    margin-bottom: var(--space-4);
}

.cta-section p {
    font-size: 1.25rem;
    margin-bottom: var(--space-8);
    opacity: 0.95;
}

.cta-buttons {
    display: flex;
    gap: var(--space-4);
    justify-content: center;
    margin-top: var(--space-8);
}

/* Footer */
footer {
    background: var(--gray-900);
    color: var(--gray-300);
    padding: var(--space-16) 0 var(--space-8);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: var(--space-12);
    margin-bottom: var(--space-12);
}

.footer-section h4 {
    color: #fff;
    font-weight: 600;
    margin-bottom: var(--space-4);
}

.footer-section ul { list-style: none; }
.footer-section li { margin-bottom: var(--space-2); }

.footer-section a {
    color: var(--gray-400);
    text-decoration: none;
    transition: color var(--duration-base) var(--ease);
}

.footer-section a:hover { color: var(--green-400); }

.footer-bottom {
    border-top: 1px solid var(--gray-800);
    padding-top: var(--space-6);
    text-align: center;
    color: var(--gray-500);
}

/* Responsive */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: #fff;
        flex-direction: column;
        gap: 0;
        padding: var(--space-4);
        box-shadow: var(--shadow-lg);
        border-top: 1px solid var(--gray-200);
    }

    .nav-links.active { display: flex; }
    .mobile-menu-toggle { display: flex; }

    .mobile-menu-toggle.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
    .mobile-menu-toggle.active span:nth-child(2) { opacity: 0; }
    .mobile-menu-toggle.active span:nth-child(3) { transform: rotate(-45deg) translate(7px, -6px); }

    .dropdown-menu {
        position: static;
        opacity: 1;
        visibility: visible;
        transform: none;
        box-shadow: none;
        border: none;
        margin-left: var(--space-4);
        display: none;
    }

    .dropdown.active .dropdown-menu { display: block; }

    .hero-content {
        grid-template-columns: 1fr;
        gap: var(--space-8);
    }

    .hero-text { order: -1; }
    .hero-image img { max-width: 80%; }

    .features-grid,
    .benefits-grid { grid-template-columns: 1fr; }

    .stats-grid { grid-template-columns: repeat(2, 1fr); gap: var(--space-4); }
    .pricing-grid { grid-template-columns: 1fr; }
    .pricing-card.featured { transform: none; }

    .app-store-links,
    .cta-buttons { flex-direction: column; align-items: center; }
}

@media (max-width: 480px) {
    .stats-grid { grid-template-columns: 1fr; }
    .stat-number { font-size: 2rem; }
}