/* =========================================
   PD Engineering - Design System & Styles
   ========================================= */

/* --- CSS Variables --- */
:root {
    /* Colors */
    --color-primary: #121A2F;      /* Deep Industrial Navy */
    --color-primary-light: #1F2C4C; 
    --color-accent: #F4C430;       /* Warning/Safety Yellow */
    --color-accent-hover: #E0B120;
    
    --color-text-dark: #333333;
    --color-text-light: #666666;
    --color-white: #FFFFFF;
    --color-bg-light: #F8F9FA;
    --color-border: #E2E8F0;

    /* Typography */
    --font-heading: 'Outfit', sans-serif;
    --font-body: 'Inter', sans-serif;
    
    /* Spacing */
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 2rem;
    --space-xl: 4rem;
    --space-xxl: 6rem;
    
    /* Utilities */
    --border-radius: 8px;
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --shadow-sm: 0 2px 4px rgba(0,0,0,0.05);
    --shadow-md: 0 10px 20px rgba(0,0,0,0.1);
    --shadow-lg: 0 20px 40px rgba(0,0,0,0.15);
}

/* --- Reset & Global --- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

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

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--space-md);
    color: var(--color-primary);
}

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

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

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

ul {
    list-style: none;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-md);
}

.section-padding {
    padding: var(--space-xxl) 0;
}

.text-center { text-align: center; }
.mt-2 { margin-top: var(--space-lg); }
.mt-3 { margin-top: calc(var(--space-lg) * 1.5); }
.mt-4 { margin-top: var(--space-xl); }
.bg-light { background-color: var(--color-bg-light); }
.bg-navy { background-color: var(--color-primary); }
.bg-yellow { background-color: var(--color-accent); }
.text-white { color: var(--color-white); }
.text-light-gray { color: #A0AEC0; }

/* --- Buttons --- */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    font-family: var(--font-heading);
    font-weight: 600;
    text-align: center;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all var(--transition-fast);
    border: none;
}

.btn-primary {
    background-color: var(--color-accent);
    color: var(--color-primary);
}
.btn-primary:hover {
    background-color: var(--color-accent-hover);
    color: var(--color-primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-primary-dark {
    background-color: var(--color-primary);
    color: var(--color-white);
}
.btn-primary-dark:hover {
    background-color: var(--color-primary-light);
    color: var(--color-white);
}

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

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

.btn-large {
    padding: 1rem 2rem;
    font-size: 1.125rem;
}

.btn-text {
    background: none;
    color: var(--color-accent);
    padding: 0;
    font-weight: 700;
    display: inline-flex;
    align-items: center;
}
.bg-light .btn-text {
    color: var(--color-primary);
}
.bg-light .btn-text:hover {
    color: var(--color-accent);
}

/* --- Header & Navigation --- */
#main-header {
    background-color: var(--color-white);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    width: 100%;
    z-index: 1000;
    transition: all var(--transition-fast);
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
}

.logo-text {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    color: var(--color-primary);
    letter-spacing: 0.5px;
}
.logo-text strong {
    color: var(--color-accent);
    font-weight: 800;
}

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

.main-nav a {
    font-family: var(--font-heading);
    font-weight: 600;
    color: var(--color-primary);
    font-size: 0.95rem;
}

.main-nav a:hover, .main-nav a.active {
    color: var(--color-accent);
}

/* Dropdown */
.dropdown {
    position: relative;
}
.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    background: var(--color-white);
    box-shadow: var(--shadow-md);
    min-width: 220px;
    border-radius: var(--border-radius);
    padding: 0.5rem 0;
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: all var(--transition-fast);
    z-index: 100;
}
.dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}
.dropdown-menu li {
    padding: 0;
}
.dropdown-menu a {
    display: block;
    padding: 0.5rem 1.5rem;
    font-weight: 500;
    border-bottom: 1px solid var(--color-border);
}
.dropdown-menu li:last-child a { border-bottom: none; }
.dropdown-menu a:hover {
    background-color: var(--color-bg-light);
    padding-left: 1.75rem; /* slight indent on hover */
}

.mobile-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    flex-direction: column;
    gap: 5px;
}
.mobile-toggle span {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--color-primary);
    transition: var(--transition-fast);
}

/* --- Hero Section --- */
.hero {
    position: relative;
    padding: 6rem 0;
    min-height: 450px;
    display: flex;
    align-items: center;
    background-color: var(--color-primary);
    background-image: 
        radial-gradient(circle at 15% 50%, rgba(244, 196, 48, 0.15), transparent 25%),
        radial-gradient(circle at 85% 30%, rgba(244, 196, 48, 0.1), transparent 25%),
        linear-gradient(135deg, var(--color-primary) 0%, #0d1222 100%);
    color: var(--color-white);
    overflow: hidden;
}
.hero::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background-image: radial-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px);
    background-size: 20px 20px;
    z-index: 1;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at center, rgba(0,0,0,0.2) 0%, rgba(18,26,47,0.8) 100%);
    z-index: 1;
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 900px;
    text-align: center;
    margin: 0 auto;
}

.hero-badge {
    display: inline-block;
    padding: 0.5rem 1.25rem;
    background-color: rgba(244, 196, 48, 0.1);
    border: 1px solid var(--color-accent);
    color: var(--color-accent);
    border-radius: 50px;
    font-weight: 600;
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
    letter-spacing: 1px;
    text-transform: uppercase;
}

.hero h1 {
    color: var(--color-white);
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    line-height: 1.1;
}

.hero-subtitle {
    font-size: 1.5rem;
    color: var(--color-accent);
    font-weight: 500;
    margin-bottom: 2.5rem;
}

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

/* --- Split Layouts (About, Quality) --- */
.split-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}
.split-layout.reverse .split-content {
    order: 2;
}
.split-layout.reverse .split-image {
    order: 1;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    position: relative;
    padding-bottom: 1rem;
}
.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 60px;
    height: 4px;
    background-color: var(--color-accent);
    border-radius: 2px;
}
.text-center .section-title::after {
    left: 50%;
    transform: translateX(-50%);
}

.split-content p {
    margin-bottom: 1.5rem;
    color: var(--color-text-light);
    font-size: 1.1rem;
}
.bg-navy .split-content p { color: var(--color-white); }
.bg-navy .section-title { color: var(--color-white); }

.feature-list {
    margin-bottom: 2rem;
}
.feature-list li {
    position: relative;
    padding-left: 2rem;
    margin-bottom: 0.75rem;
    font-weight: 600;
    color: var(--color-primary);
}
.feature-list li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--color-accent);
    font-weight: bold;
}

.placeholder-image {
    background-color: #E2E8F0;
    border-radius: var(--border-radius);
    height: 400px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #A0AEC0;
    font-weight: bold;
    box-shadow: var(--shadow-lg);
    border: 1px dashed #CBD5E0;
}

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

.product-card {
    background: var(--color-white);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-border);
    transition: all var(--transition-normal);
}
.product-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
    border-color: var(--color-accent);
}

.card-img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    background-color: #EDF2F7;
    border-radius: 0; /* overrides placeholder default */
    border: none;
    border-bottom: 1px solid var(--color-border);
}

.card-content {
    padding: 1.5rem;
}

.card-content h3 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
}
.card-content p {
    color: var(--color-text-light);
    font-size: 0.95rem;
    margin-bottom: 1.5rem;
}

.card-link {
    font-family: var(--font-heading);
    font-weight: 700;
    color: var(--color-primary);
    text-transform: uppercase;
    font-size: 0.85rem;
    letter-spacing: 0.5px;
    display: inline-flex;
    align-items: center;
}
.card-link::after {
    content: '→';
    margin-left: 5px;
    transition: transform var(--transition-fast);
}
.product-card:hover .card-link {
    color: var(--color-accent);
}
.product-card:hover .card-link::after {
    transform: translateX(5px);
}

/* --- Advantages --- */
.advantages-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 4rem;
}

.advantage-item {
    text-align: center;
    padding: 2rem;
    background: rgba(255,255,255,0.05);
    border-radius: var(--border-radius);
    border: 1px solid rgba(255,255,255,0.1);
    transition: var(--transition-normal);
}
.advantage-item:hover {
    background: rgba(255,255,255,0.1);
    transform: translateY(-5px);
    border-color: var(--color-accent);
}

.advantage-item .icon {
    font-size: 3rem;
    margin-bottom: 1.5rem;
    color: var(--color-accent);
}
.advantage-item h3 {
    color: var(--color-white);
    font-size: 1.25rem;
    margin-bottom: 1rem;
}
.advantage-item p {
    color: var(--color-text-light);
}
.bg-navy .advantage-item p { color: #CBD5E0; }

/* --- Industries Cards --- */
.industries-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.industry-card {
    background: var(--color-white);
    border: 1px solid var(--color-border);
    padding: 2.5rem 1.5rem;
    border-radius: var(--border-radius);
    text-align: center;
    transition: var(--transition-normal);
    box-shadow: var(--shadow-sm);
    position: relative;
    overflow: hidden;
}
.industry-card::before {
    content: '';
    position: absolute;
    top: 0; left: 0; width: 100%; height: 4px;
    background-color: var(--color-accent);
    transform: scaleX(0);
    transition: transform var(--transition-normal);
    transform-origin: left;
}
.industry-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--color-border);
}
.industry-card:hover::before {
    transform: scaleX(1);
}
.industry-card .icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    display: inline-block;
}
.industry-card h4 {
    font-size: 1.25rem;
    margin-bottom: 0;
    color: var(--color-primary);
}
.industry-card .icon svg {
    color: var(--color-primary);
    transition: var(--transition-normal);
}
.industry-card:hover .icon svg {
    color: var(--color-accent);
}

/* --- FAQ --- */
.faq-container {
    max-width: 800px;
    margin: 3rem auto 0;
}

.faq-item {
    margin-bottom: 1rem;
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius);
    overflow: hidden;
}

.faq-question {
    width: 100%;
    background: var(--color-bg-light);
    border: none;
    padding: 1.5rem;
    text-align: left;
    font-family: var(--font-heading);
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--color-primary);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: background var(--transition-fast);
}
.faq-question:hover {
    background: #E2E8F0;
}

.faq-question .icon {
    font-size: 1.5rem;
    color: var(--color-accent);
    transition: transform var(--transition-fast);
}

.faq-answer {
    padding: 0;
    max-height: 0;
    overflow: hidden;
    background: var(--color-white);
    transition: max-height 0.3s ease, padding 0.3s ease;
}

.faq-answer p {
    color: var(--color-text-light);
}

/* Active FAQ State */
.faq-item.active .faq-answer {
    padding: 1.5rem;
    max-height: 500px; /* arbitrary large value for smooth transition */
    border-top: 1px solid var(--color-border);
}
.faq-item.active .faq-question .icon {
    transform: rotate(45deg);
}

/* --- Footer --- */
.site-footer {
    background: var(--color-primary);
    color: var(--color-white);
    padding-top: 4rem;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 4rem;
    margin-bottom: 3rem;
}

.footer-logo {
    margin-bottom: 1rem;
}
.footer-logo .logo-text { color: var(--color-white); }
.brand-col p { color: #A0AEC0; }

.footer-col h4 {
    color: var(--color-white);
    font-size: 1.25rem;
    margin-bottom: 1.5rem;
    position: relative;
    padding-bottom: 0.5rem;
}
.footer-col h4::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 30px;
    height: 3px;
    background: var(--color-accent);
}

.footer-links li, .contact-info-list li {
    margin-bottom: 0.75rem;
    color: #A0AEC0;
}
.footer-links a {
    color: #A0AEC0;
}
.footer-links a:hover {
    color: var(--color-accent);
}

.footer-bottom {
    background: #0d1222;
    padding: 1.5rem 0;
    color: #A0AEC0;
    font-size: 0.9rem;
}

/* --- Internal Pages --- */
.page-hero {
    min-height: 350px;
    height: auto;
    padding: 6rem 0 3rem;
}
.page-hero h1 {
    font-size: 3rem;
}
.page-hero .hero-badge {
    margin-bottom: 1rem;
}

/* --- Forms --- */
.contact-form {
    background: var(--color-white);
    padding: 3rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--color-border);
}
.form-group {
    margin-bottom: 1.5rem;
}
.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--color-primary);
}
.form-control {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius);
    font-family: var(--font-body);
    font-size: 1rem;
    transition: var(--transition-fast);
    background-color: var(--color-bg-light);
}
.form-control:focus {
    outline: none;
    border-color: var(--color-accent);
    background-color: var(--color-white);
    box-shadow: 0 0 0 3px rgba(244, 196, 48, 0.2);
}
textarea.form-control {
    resize: vertical;
    min-height: 120px;
}

/* --- Tables --- */
.table-container {
    overflow-x: auto;
    margin-top: 2rem;
    box-shadow: var(--shadow-sm);
    border-radius: var(--border-radius);
    border: 1px solid var(--color-border);
}
.spec-table {
    width: 100%;
    border-collapse: collapse;
    background: var(--color-white);
}
.spec-table th, .spec-table td {
    padding: 1rem 1.5rem;
    text-align: left;
    border-bottom: 1px solid var(--color-border);
}
.spec-table th {
    background-color: var(--color-primary);
    color: var(--color-white);
    font-family: var(--font-heading);
    font-weight: 600;
    text-transform: uppercase;
    font-size: 0.9rem;
    letter-spacing: 0.5px;
}
.spec-table tr:hover {
    background-color: var(--color-bg-light);
}

/* --- Responsive Design --- */
@media (max-width: 992px) {
    .split-layout {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    .split-layout.reverse .split-content { order: 1; }
    .split-layout.reverse .split-image { order: 2; }
    
    .hero h1 { font-size: 2.8rem; }
    
    .footer-grid {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    .main-nav {
        display: none; /* simple hidden for now, can implement mobile menu via JS */
        position: absolute;
        top: 80px;
        left: 0;
        width: 100%;
        background: var(--color-white);
        padding: 2rem;
        box-shadow: var(--shadow-md);
    }
    .main-nav.active {
        display: block;
    }
    .main-nav .nav-links {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    .dropdown-menu {
        position: static;
        opacity: 1;
        visibility: visible;
        transform: none;
        box-shadow: none;
        background: var(--color-bg-light);
        margin-top: 0.5rem;
        width: 100%;
    }
    .header-cta { display: none; }
    .mobile-toggle { display: flex; }
    
    .hero h1 { font-size: 2.2rem; }
    .hero-actions { flex-direction: column; width: 100%; }
    .hero-actions .btn { width: 100%; }
    
    .footer-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
}