/* --- CSS Variables & Resets --- */
:root {
    --primary-blue: #0A2540;     /* Biru Tua */
    --sea-blue: #0077B6;         /* Biru Laut */
    --light-blue: #90E0EF;       
    --text-dark: #333333;
    --text-light: #666666;
    --bg-light: #F8F9FA;
    --white: #FFFFFF;
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Poppins', sans-serif;
    color: var(--text-dark);
    line-height: 1.6;
    background-color: var(--white);
}

a {
    text-decoration: none;
    color: inherit;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
}

.section {
    padding: 80px 0;
}

.bg-light {
    background-color: var(--bg-light);
}

/* --- Typography & Elements --- */
.section-title {
    text-align: center;
    margin-bottom: 50px;
}

.section-title h2 {
    font-size: 36px;
    color: var(--primary-blue);
    margin-bottom: 10px;
}

.underline {
    width: 80px;
    height: 4px;
    background: linear-gradient(to right, var(--sea-blue), var(--primary-blue));
    margin: 0 auto;
    border-radius: 2px;
}

.btn {
    display: inline-block;
    padding: 12px 30px;
    font-size: 16px;
    font-weight: 600;
    border-radius: 5px;
    transition: var(--transition);
    cursor: pointer;
    border: 2px solid transparent;
}

.btn-primary {
    background: linear-gradient(45deg, var(--sea-blue), var(--primary-blue));
    color: var(--white);
}

.btn-primary:hover {
    box-shadow: 0 8px 15px rgba(0, 119, 182, 0.3);
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: var(--white);
    border: 2px solid var(--white);
}

.btn-secondary:hover {
    background: var(--white);
    color: var(--primary-blue);
}

.card {
    background: var(--white);
    border-radius: 10px;
    padding: 30px;
    box-shadow: 0 5px 20px rgba(0,0,0,0.05);
    transition: var(--transition);
}

/* --- Header & Navigation --- */
header {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    background: transparent;
    transition: var(--transition);
    padding: 20px 0;
}

header.scrolled {
    background: var(--primary-blue);
    padding: 15px 0;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

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

.logo img {
    height: 50px;
    filter: brightness(0) invert(1); /* Makes logo white on transparent/dark bg. Adjust based on your actual logo */
    transition: var(--transition);
}

.nav-links a {
    color: var(--white);
    margin-left: 30px;
    font-weight: 500;
    font-size: 16px;
    position: relative;
    transition: var(--transition);
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0%;
    height: 2px;
    background-color: var(--sea-blue);
    transition: var(--transition);
}

.nav-links a:hover::after {
    width: 100%;
}

.hamburger {
    display: none;
    color: var(--white);
    font-size: 24px;
    cursor: pointer;
}

/* --- Hero Section --- */
.hero {
    height: 100vh;
    background: linear-gradient(rgba(10, 37, 64, 0.7), rgba(0, 119, 182, 0.6)), url('images/hero.jpg') center/cover no-repeat;
    /* Unsplash fallback URL */
    background: linear-gradient(rgba(10, 37, 64, 0.7), rgba(0, 119, 182, 0.6)), url('https://images.unsplash.com/photo-1578575437130-527eed3abbec?auto=format&fit=crop&w=1920&q=80') center/cover no-repeat;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--white);
    padding: 0 20px;
}

.hero-content h1 {
    font-size: 56px;
    font-weight: 700;
    margin-bottom: 20px;
    line-height: 1.2;
}

.hero-content p {
    font-size: 22px;
    margin-bottom: 40px;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
}

/* --- About Us --- */
.about-text {
    text-align: center;
    max-width: 800px;
    margin: 0 auto 50px auto;
    font-size: 18px;
    color: var(--text-light);
}

.about-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

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

.about-card i {
    font-size: 40px;
    color: var(--sea-blue);
    margin-bottom: 20px;
}

.about-card h3 {
    color: var(--primary-blue);
    margin-bottom: 15px;
}

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

.service-card {
    text-align: center;
    border-bottom: 4px solid transparent;
}

.service-card:hover {
    transform: translateY(-10px);
    border-bottom: 4px solid var(--sea-blue);
}

.service-card i {
    font-size: 50px;
    color: var(--sea-blue);
    margin-bottom: 20px;
}

.service-card h3 {
    color: var(--primary-blue);
    margin-bottom: 15px;
}

/* --- Projects --- */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.project-item {
    position: relative;
    overflow: hidden;
    border-radius: 10px;
    height: 250px;
}

.project-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.project-info {
    position: absolute;
    bottom: -100%;
    left: 0;
    width: 100%;
    padding: 20px;
    background: linear-gradient(to top, rgba(10,37,64,0.9), transparent);
    color: var(--white);
    transition: bottom 0.4s ease;
}

.project-item:hover img {
    transform: scale(1.1);
}

.project-item:hover .project-info {
    bottom: 0;
}

/* --- Gallery --- */
.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 15px;
}

.gallery-grid img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: 10px;
    transition: var(--transition);
    cursor: pointer;
}

.gallery-grid img:hover {
    transform: scale(1.05);
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
}

/* --- Contact --- */
.contact-wrapper {
    display: flex;
    flex-wrap: wrap;
    gap: 50px;
}

.contact-info, .contact-form {
    flex: 1;
    min-width: 300px;
}

.contact-info h3 {
    font-size: 28px;
    color: var(--primary-blue);
    margin-bottom: 15px;
}

.info-item {
    display: flex;
    align-items: center;
    margin-bottom: 20px;
}

.info-item i {
    font-size: 20px;
    color: var(--sea-blue);
    width: 30px;
}

.map-container {
    margin-top: 30px;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--primary-blue);
}

.form-group input, .form-group textarea {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-family: 'Poppins', sans-serif;
    outline: none;
    transition: var(--transition);
}

.form-group input:focus, .form-group textarea:focus {
    border-color: var(--sea-blue);
    box-shadow: 0 0 5px rgba(0,119,182,0.3);
}

/* --- Footer --- */
.footer {
    background: var(--primary-blue);
    color: var(--white);
    padding: 60px 0 20px 0;
}

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

.footer-logo {
    height: 60px;
    margin-bottom: 20px;
    filter: brightness(0) invert(1);
}

.footer-col h4 {
    font-size: 20px;
    margin-bottom: 20px;
    position: relative;
    padding-bottom: 10px;
}

.footer-col h4::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    width: 40px;
    height: 3px;
    background: var(--sea-blue);
}

.footer-col ul {
    list-style: none;
}

.footer-col ul li {
    margin-bottom: 10px;
}

.footer-col ul li a {
    transition: var(--transition);
}

.footer-col ul li a:hover {
    color: var(--sea-blue);
    padding-left: 5px;
}

.social-icons {
    margin-top: 20px;
}

.social-icons a {
    display: inline-block;
    width: 40px;
    height: 40px;
    background: rgba(255,255,255,0.1);
    text-align: center;
    line-height: 40px;
    border-radius: 50%;
    margin-right: 10px;
    transition: var(--transition);
}

.social-icons a:hover {
    background: var(--sea-blue);
    transform: translateY(-3px);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255,255,255,0.1);
    font-size: 14px;
}

/* --- WhatsApp Button --- */
.wa-float {
    position: fixed;
    width: 60px;
    height: 60px;
    bottom: 30px;
    right: 30px;
    background-color: #25d366;
    color: #FFF;
    border-radius: 50px;
    text-align: center;
    font-size: 35px;
    box-shadow: 2px 2px 10px rgba(0,0,0,0.2);
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.wa-float:hover {
    transform: scale(1.1);
    box-shadow: 2px 2px 15px rgba(37, 211, 102, 0.5);
}

/* --- Responsive Design --- */
@media (max-width: 768px) {
    .nav-links {
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background: var(--primary-blue);
        flex-direction: column;
        display: none;
        padding: 20px 0;
    }

    .nav-links.active {
        display: flex;
    }

    .nav-links a {
        margin: 15px 0;
        text-align: center;
    }

    .hamburger {
        display: block;
    }

    .hero-content h1 {
        font-size: 40px;
    }
    
    .hero-buttons {
        flex-direction: column;
    }
}