:root {
    --primary-dark: #1e3c72;
    --primary-light: #2a5298;
    --text-dark: #333;
    --background-light: #f8f9fa;
    --white: #ffffff;
    --header-dark: #2d3748;
    --header-light: #4a5568;
}

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

body {
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    scroll-behavior: smooth;
}

h1 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    text-align: center;
}

h2 {
    font-size: 2.5rem;
    margin-bottom: 2rem;
    text-align: center;
}

h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    text-align: center;
}

p {
    font-size: 1.1rem;
    margin-bottom: 1rem;
    text-align: center;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

header {
    background: linear-gradient(135deg, var(--header-dark) 0%, var(--header-light) 100%);
    color: var(--white);
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.nav-menu {
    list-style: none;
    display: flex;
    justify-content: center;
    gap: 30px;
}

.mobile-menu {
    display: none;
}

nav a {
    color: var(--white);
    text-decoration: none;
    font-weight: 500;
    transition: opacity 0.3s;
}

nav a:hover {
    opacity: 0.8;
}

section {
    padding: 100px 0;
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.hero {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-light) 100%);
    color: var(--white);
    text-align: center;
}

.hero h1 {
    animation: fadeInUp 1s ease;
}

.hero p:nth-child(2) {
    animation: fadeInUp 1s ease 0.3s both;
}

.hero p:nth-child(3) {
    animation: fadeInUp 1s ease 0.6s both;
}

.hero p:nth-child(4) {
    animation: fadeInUp 1s ease 0.9s both;
}

.services {
    background: var(--white);
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-top: 50px;
}

.service-card {
    background: var(--background-light);
    padding: 30px;
    border-radius: 10px;
    text-align: center;
    transition: transform 0.3s, box-shadow 0.3s;
}

.service-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.about {
    background: var(--background-light);
}

.skills {
    background: var(--white);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-top: 50px;
}

.skill-card {
    background: var(--background-light);
    padding: 30px;
    border-radius: 10px;
    text-align: center;
    transition: transform 0.3s, box-shadow 0.3s;
}

.skill-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.customers {
    background: var(--background-light);
}

.customers-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-top: 50px;
}

.customer-card {
    background: var(--white);
    padding: 40px 20px;
    border-radius: 12px;
    text-align: center;
    transition: all 0.3s ease;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    border: 2px solid transparent;
    color: var(--text-dark);
}

.customer-link {
    text-decoration: none;
    color: inherit;
    display: inline-block;
    transition: transform 0.3s ease;
}

.customer-link:hover {
    transform: scale(1.05);
}

.customer-header {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    margin-bottom: 1.5rem;
}

.customer-logo {
    font-size: 1.8rem;
    font-weight: 700;
    letter-spacing: 1px;
    margin: 0;
}

.customer-logo-img {
    max-height: 50px;
    height: auto;
}

.customer-info {
    min-height: 100px;
}

.expand-toggle {
    background: var(--primary-light);
    color: var(--white);
    border: none;
    padding: 12px 24px;
    border-radius: 8px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
    margin: 20px auto;
    font-weight: 500;
}

.expand-toggle:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(30, 60, 114, 0.3);
}

.expand-icon {
    font-size: 1.3rem;
    font-weight: bold;
    transition: transform 0.3s ease;
}

.expand-toggle.active .expand-icon {
    transform: rotate(45deg);
}

.customer-details {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.5s ease, opacity 0.3s ease;
    opacity: 0;
    text-align: left;
}

.customer-details.expanded {
    max-height: 1000px;
    opacity: 1;
    margin-top: 20px;
}

.contact {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-light) 100%);
    color: var(--white);
    text-align: center;
}

.contact-info {
    display: inline-block;
    margin-top: 40px;
    color: var(--white);
    text-decoration: none;
}

.contact-info:hover {
    opacity: 0.8;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@media (max-width: 768px) {
    header {
        padding: 1.5rem 0;
    }

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

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

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

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

    .customer-card {
        padding: 30px 15px;
    }

    .customer-logo {
        font-size: 1.5rem;
    }

    .contact-info {
        flex-direction: column;
        gap: 30px;
    }

    .mobile-menu {
        display: flex;
        background: none;
        border: none;
        cursor: pointer;
        flex-direction: column;
        gap: 4px;
        padding: 8px;
        position: absolute;
        right: 20px;
        top: 50%;
        transform: translateY(-50%);
        z-index: 1001;
    }

    .mobile-menu span {
        width: 25px;
        height: 3px;
        background: var(--white);
        border-radius: 2px;
        transition: all 0.3s ease;
    }

    .mobile-menu.active span:nth-child(1) {
        transform: rotate(45deg) translateY(10px);
    }

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

    .mobile-menu.active span:nth-child(3) {
        transform: rotate(-45deg) translateY(-10px);
    }

    .nav-menu {
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background: linear-gradient(135deg, var(--header-dark) 0%, var(--header-light) 100%);
        flex-direction: column;
        gap: 0;
        padding: 0;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.3s ease;
        box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    }

    .nav-menu.active {
        max-height: 300px;
    }

    .nav-menu li {
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    }

    .nav-menu li:last-child {
        border-bottom: none;
    }

    .nav-menu a {
        display: block;
        padding: 15px 20px;
        text-align: center;
        transition: background-color 0.3s ease;
    }

    .nav-menu a:hover {
        background-color: rgba(255, 255, 255, 0.1);
    }
}