:root {
    --bg-color: #0a0f1c;
    --bg-secondary: #111827;
    --text-primary: #f3f4f6;
    --text-secondary: #9ca3af;
    --accent-color: #0ea5e9;
    /* Sky blue */
    --accent-glow: rgba(14, 165, 233, 0.5);
    --gradient-start: #0ea5e9;
    --gradient-end: #22d3ee;
    /* Cyan */

    --font-main: 'Inter', sans-serif;

    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;

    --container-width: 1200px;
    --border-radius: 8px;
    --transition: all 0.3s ease;
}

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

body {
    font-family: var(--font-main);
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

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

ul {
    list-style: none;
}

img {
    max-width: 100%;
    display: block;
}

/* Utilities */
.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 var(--spacing-sm);
}

.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    font-weight: 600;
    cursor: pointer;
    border: none;
    transition: var(--transition);
}

.btn-primary {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    color: #000;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px var(--accent-glow);
}

.btn-secondary {
    background: transparent;
    border: 1px solid var(--text-secondary);
    color: var(--text-primary);
}

.btn-secondary:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
}

.text-gradient {
    background: linear-gradient(to right, var(--gradient-start), var(--gradient-end));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.section {
    padding: var(--spacing-lg) 0;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-md);
    text-align: center;
}

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: rgba(10, 15, 28, 0.9);
    backdrop-filter: blur(10px);
    z-index: 1000;
    padding: 1rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
}

.logo .accent {
    color: var(--accent-color);
}

.nav-list {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.nav-list a:not(.btn) {
    color: var(--text-secondary);
}

.nav-list a:not(.btn):hover {
    color: var(--text-primary);
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
}

.mobile-menu-btn .bar {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--text-primary);
    margin: 5px 0;
    transition: var(--transition);
}

/* Hero */
.hero {
    padding-top: 8rem;
    /* Header offset */
    min-height: 90vh;
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -20%;
    right: -10%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, var(--accent-glow) 0%, transparent 70%);
    opacity: 0.4;
    z-index: -1;
}

.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-md);
    align-items: center;
}

.hero-content h1 {
    font-size: 3.5rem;
    line-height: 1.2;
    margin-bottom: 1.5rem;
}

.hero-content p {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    max-width: 500px;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
}

.data-orb {
    width: 400px;
    height: 400px;
    background: radial-gradient(circle at 30% 30%, var(--bg-secondary), var(--bg-color));
    border-radius: 50%;
    box-shadow: 0 0 60px var(--accent-glow), inset 0 0 20px rgba(255, 255, 255, 0.1);
    position: relative;
    margin: 0 auto;
    animation: float 6s ease-in-out infinite;
}

@keyframes float {

    0%,
    100% {
        transform: translateY(0);
    }

    50% {
        transform: translateY(-20px);
    }
}

/* Services */
.services {
    background-color: var(--bg-secondary);
}

.grid {
    display: grid;
    gap: var(--spacing-md);
}

.services-grid {
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.card {
    background-color: var(--bg-color);
    padding: 2rem;
    border-radius: var(--border-radius);
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: var(--transition);
}

.card:hover {
    border-color: var(--accent-color);
    transform: translateY(-5px);
}

.card .icon {
    margin-bottom: 1rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 60px;
    height: 60px;
    background: rgba(14, 165, 233, 0.1);
    border-radius: 12px;
    color: var(--accent-color);
}

.card .icon svg {
    width: 32px;
    height: 32px;
    filter: drop-shadow(0 0 5px var(--accent-glow));
}

.card h3 {
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

.card p {
    color: var(--text-secondary);
}

/* Tech Stack */
.tech-stack {
    background-color: var(--bg-secondary);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.tech-grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 2rem;
    align-items: center;
}

.tech-item {
    width: 140px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
    color: var(--text-secondary);
    transition: var(--transition);
    opacity: 0.7;
    text-align: center;
}

.tech-item:hover {
    color: var(--text-primary);
    opacity: 1;
    transform: translateY(-5px);
}

.tech-logo {
    width: 60px;
    height: 60px;
    /* Ensure SVGs loaded as images behave well */
    display: block;
    /* Optional: if you want them to be monochrome by default and colored on hover, 
       you can use filters, but standard images usually keep their colors. 
       If the user wants them monochrome, we can use grayscale filter. */
    filter: grayscale(100%);
    transition: var(--transition);
}

.tech-item:hover .tech-logo {
    filter: grayscale(0%);
}

.tech-item span {
    font-size: 1.1rem;
    font-weight: 600;
}

/* Clients */
.clients {
    background-color: var(--bg-secondary);
    padding: var(--spacing-lg) 0;
}

.clients-grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 4rem;
    align-items: center;
    opacity: 0.6;
}

.client-item {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-secondary);
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
}

.client-item:hover {
    opacity: 1;
    color: var(--text-primary);
    transform: scale(1.05);
}

.client-logo-svg {
    width: 100px;
    height: 40px;
    fill: currentColor;
}

.client-name {
    font-family: var(--font-main);
    letter-spacing: -0.02em;
}

/* Benefits */
.benefits-grid {
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.benefit-item {
    padding: 1.5rem;
    border-left: 3px solid var(--accent-color);
}

.benefit-item h3 {
    margin-bottom: 0.5rem;
    font-size: 1.25rem;
}

.benefit-item p {
    color: var(--text-secondary);
}

/* Contact */
.contact-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
}

.contact-info h2 {
    margin-bottom: 1rem;
}

.contact-info p {
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.contact-details li {
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 0.75rem;
}

.contact-icon {
    width: 24px;
    height: 24px;
    color: var(--accent-color);
    flex-shrink: 0;
}

.contact-details a:hover {
    color: var(--accent-color);
}

.contact-form {
    background-color: var(--bg-secondary);
    padding: 2rem;
    border-radius: var(--border-radius);
}

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

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    background-color: var(--bg-color);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 4px;
    color: var(--text-primary);
    font-family: inherit;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent-color);
}

/* Footer */
.footer {
    padding: 2rem 0;
    text-align: center;
    color: var(--text-secondary);
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

/* Responsive */
@media (max-width: 768px) {

    .hero-container,
    .contact-container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-buttons {
        justify-content: center;
    }

    .hero-visual {
        order: -1;
    }

    .nav {
        display: none;
        /* Implement mobile menu logic in JS */
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background-color: var(--bg-secondary);
        padding: 1rem;
    }

    .nav.active {
        display: block;
    }

    .nav-list {
        flex-direction: column;
    }

    .mobile-menu-btn {
        display: block;
    }
}