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

:root {
  --primary-color: #6366f1;
  --secondary-color: #8b5cf6;
  --accent-color: #06d6a0;
  --text-primary: #1f2937;
  --text-secondary: #6b7280;
  --bg-light: #f9fafb;
  --bg-white: #ffffff;
  --border-color: #e5e7eb;
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  --gradient: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  --transition: all 0.3s ease;
}

body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-white);
}

/* HEADER NAVIGATION */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-color);
  z-index: 1000;
  transition: var(--transition);
}

.header.scrolled {
            box-shadow: var(--shadow);
        }

        .nav {
            max-width: 1200px;
            margin: 0 auto;
            padding: 1rem 2rem;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .logo {
            font-size: 1.5rem;
            font-weight: 700;
            background: var(--gradient);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        .nav-menu {
            display: flex;
            list-style: none;
            gap: 2rem;
        }

        .nav-link {
            text-decoration: none;
            color: var(--text-primary);
            font-weight: 500;
            transition: var(--transition);
            position: relative;
        }

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

        .nav-link::after {
            content: '';
            position: absolute;
            bottom: -5px;
            left: 0;
            width: 0;
            height: 2px;
            background: var(--primary-color);
            transition: var(--transition);
        }

        .nav-link:hover::after,
        .nav-link.active::after {
            width: 100%;
        }

        .menu-toggle {
            display: none;
            flex-direction: column;
            cursor: pointer;
            padding: 0.5rem;
        }

        .menu-toggle span {
            width: 25px;
            height: 3px;
            background: var(--text-primary);
            margin: 3px 0;
            transition: var(--transition);
        }

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

        .menu-toggle.active span:nth-child(2) {
            opacity: 0;
        }

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

        /* MAIN CONTENT =*/
        .main {
            margin-top: 80px;
        }

        .page {
            display: none;
        }

        .page.active {
            display: block;
        }

        /*HERO SECTION*/
        .hero {
            background: var(--gradient);
            color: white;
            padding: 6rem 2rem;
            text-align: center;
            position: relative;
            overflow: hidden;
        }

        .hero::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: url('data:image/svg+xml,<svg xmlns="" viewBox="0 0 1000 1000"><polygon fill="rgba(255,255,255,0.1)" points="0,0 1000,300 1000,1000 0,700"/></svg>');
            background-size: cover;
        }

        .hero-content {
            position: relative;
            z-index: 2;
            max-width: 800px;
            margin: 0 auto;
        }

        .hero h1 {
            font-size: 3.5rem;
            font-weight: 700;
            margin-bottom: 1rem;
            opacity: 0;
            transform: translateY(30px);
            animation: fadeInUp 1s ease forwards;
        }

        .hero p {
            font-size: 1.3rem;
            margin-bottom: 2rem;
            opacity: 0;
            transform: translateY(30px);
            animation: fadeInUp 1s ease 0.2s forwards;
        }

        .cta-button {
            display: inline-block;
            background: var(--accent-color);
            color: white;
            padding: 1rem 2rem;
            border: none;
            border-radius: 50px;
            font-size: 1.1rem;
            font-weight: 600;
            text-decoration: none;
            cursor: pointer;
            transition: var(--transition);
            opacity: 0;
            transform: translateY(30px);
            animation: fadeInUp 1s ease 0.4s forwards;
        }

        .cta-button:hover {
            transform: translateY(-3px);
            box-shadow: var(--shadow-lg);
        }

        /*SECTIONS*/
        .section {
            padding: 5rem 2rem;
        }

        .container {
            max-width: 1200px;
            margin: 0 auto;
        }

        .section-title {
            text-align: center;
            font-size: 2.5rem;
            font-weight: 700;
            margin-bottom: 3rem;
            background: var(--gradient);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        /* CARDS & GRID */
        .grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 2rem;
            margin-top: 3rem;
        }

        .card {
            background: var(--bg-white);
            border-radius: 15px;
            padding: 2rem;
            box-shadow: var(--shadow);
            transition: var(--transition);
            border: 1px solid var(--border-color);
        }

        .card:hover {
            transform: translateY(-5px);
            box-shadow: var(--shadow-lg);
        }

        .card-icon {
            width: 60px;
            height: 60px;
            background: var(--gradient);
            border-radius: 12px;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 1rem;
            color: white;
            font-size: 1.5rem;
        }

        .card h3 {
            font-size: 1.3rem;
            font-weight: 600;
            margin-bottom: 1rem;
            color: var(--text-primary);
        }

        .card p {
            color: var(--text-secondary);
            margin-bottom: 1.5rem;
        }

        /* FORMS */
        .form-group {
            margin-bottom: 1.5rem;
        }

        .form-label {
            display: block;
            margin-bottom: 0.5rem;
            font-weight: 500;
            color: var(--text-primary);
        }

        .form-input {
            width: 100%;
            padding: 0.75rem 1rem;
            border: 2px solid var(--border-color);
            border-radius: 8px;
            font-size: 1rem;
            transition: var(--transition);
            background: var(--bg-white);
        }

        .form-input:focus {
            outline: none;
            border-color: var(--primary-color);
            box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
        }

        .form-input.error {
            border-color: #ef4444;
        }

        .form-input.success {
            border-color: var(--accent-color);
        }

        .error-message {
            color: #ef4444;
            font-size: 0.875rem;
            margin-top: 0.5rem;
            display: none;
        }

        .error-message.show {
            display: block;
        }

        /* FOOTER*/
        .footer {
            background: var(--text-primary);
            color: white;
            padding: 3rem 2rem 2rem;
            margin-top: 5rem;
        }

        .footer-content {
            max-width: 1200px;
            margin: 0 auto;
            text-align: center;
        }

        .footer p {
            opacity: 0.8;
            margin-bottom: 1rem;
        }

        .social-links {
            display: flex;
            justify-content: center;
            gap: 1rem;
            margin-top: 2rem;
        }

        .social-link {
            display: inline-block;
            width: 40px;
            height: 40px;
            background: rgba(255, 255, 255, 0.1);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            color: white;
            text-decoration: none;
            transition: var(--transition);
        }

        .social-link:hover {
            background: var(--primary-color);
            transform: translateY(-2px);
        }

        /*ANIMATIONS*/
        @keyframes fadeInUp {
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        .fade-in {
            opacity: 0;
            transform: translateY(20px);
            transition: all 0.6s ease;
        }

        .fade-in.visible {
            opacity: 1;
            transform: translateY(0);
        }

        /* RESPONSIVE DESIGN */
        @media (max-width: 768px) {
            .nav-menu {
                position: fixed;
                top: 100%;
                left: 0;
                right: 0;
                background: white;
                flex-direction: column;
                padding: 2rem;
                box-shadow: var(--shadow);
                transform: translateX(-100%);
                transition: var(--transition);
            }

            .nav-menu.active {
                transform: translateX(0);
            }

            .menu-toggle {
                display: flex;
            }

            .hero h1 {
                font-size: 2.5rem;
            }

            .hero p {
                font-size: 1.1rem;
            }

            .section {
                padding: 3rem 1rem;
            }

            .nav {
                padding: 1rem;
            }

            .grid {
                grid-template-columns: 1fr;
            }
        }

        /* UTILITY CLASSES  */
        .text-center { text-align: center; }
        .mt-2 { margin-top: 1rem; }
        .mb-2 { margin-bottom: 1rem; }
        .hidden { display: none; }
        .visible { display: block; }

        /*  LOADING ANIMATION  */
        .loading {
            display: inline-block;
            width: 20px;
            height: 20px;
            border: 3px solid rgba(255, 255, 255, 0.3);
            border-radius: 50%;
            border-top-color: white;
            animation: spin 1s ease-in-out infinite;
        }

        @keyframes spin {
            to { transform: rotate(360deg); }
        }