/* ============================================
   Prakash Eco Energy — Corporate Bio Fuel Website
   ============================================ */

/* --- Design Tokens --- */
:root {
    --color-primary: #1B3D2F;
    --color-primary-light: #2A5C47;
    --color-primary-dark: #0F2A1E;
    --color-accent: #C8965A;
    --color-accent-light: #D4A76E;
    --color-surface: #FAFAF7;
    --color-surface-warm: #F5F2EC;
    --color-text: #2C2C2C;
    --color-text-secondary: #6B6B6B;
    --color-text-muted: #9A9A9A;
    --color-border: #E5E2DC;
    --color-white: #FFFFFF;
    --color-dark: #1A1A1A;

    --font-display: 'DM Serif Display', Georgia, serif;
    --font-body: 'Plus Jakarta Sans', -apple-system, sans-serif;

    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 1.5rem;
    --space-lg: 3rem;
    --space-xl: 5rem;
    --space-2xl: 8rem;

    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 16px;
    --radius-xl: 24px;

    --shadow-sm: 0 1px 3px rgba(27,61,47,0.06);
    --shadow-md: 0 4px 16px rgba(27,61,47,0.08);
    --shadow-lg: 0 12px 40px rgba(27,61,47,0.1);
    --shadow-xl: 0 24px 60px rgba(27,61,47,0.12);

    --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

/* --- Reset & Base --- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-body);
    color: var(--color-text);
    background-color: var(--color-surface);
    line-height: 1.7;
    font-size: 16px;
    overflow-x: hidden;
}

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

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

ul { list-style: none; }

address { font-style: normal; }

.container {
    width: 92%;
    max-width: 1200px;
    margin: 0 auto;
}

/* --- Typography --- */
h1, h2, h3, h4 {
    font-family: var(--font-display);
    font-weight: 400;
    line-height: 1.15;
}

h1 { font-size: clamp(2.6rem, 5.5vw, 4.2rem); }
h2 { font-size: clamp(2rem, 4vw, 3rem); }
h3 { font-size: 1.25rem; font-family: var(--font-body); font-weight: 600; }
h4 { font-size: 1rem; font-family: var(--font-body); font-weight: 600; letter-spacing: 0.02em; }

em { font-style: italic; color: var(--color-accent); }

/* --- Section Foundations --- */
.section {
    padding: var(--space-2xl) 0;
    position: relative;
}

.section-header {
    text-align: center;
    max-width: 640px;
    margin: 0 auto var(--space-xl);
}

.section-tag {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--color-accent);
    margin-bottom: var(--space-sm);
    position: relative;
    padding-left: 2rem;
}

.section-tag::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    width: 1.25rem;
    height: 2px;
    background: var(--color-accent);
}

.section-header h2 {
    color: var(--color-primary);
    margin-bottom: var(--space-sm);
}

.section-desc {
    color: var(--color-text-secondary);
    font-size: 1.05rem;
}

/* --- Buttons --- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.85rem 2rem;
    border-radius: var(--radius-sm);
    font-family: var(--font-body);
    font-weight: 600;
    font-size: 0.9rem;
    letter-spacing: 0.02em;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.btn-primary {
    background: var(--color-primary);
    color: var(--color-white);
    border-color: var(--color-primary);
}

.btn-primary:hover {
    background: var(--color-primary-light);
    border-color: var(--color-primary-light);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

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

.btn-light:hover {
    background: var(--color-surface-warm);
    border-color: var(--color-surface-warm);
    transform: translateY(-1px);
}

.btn-outline {
    background: transparent;
    color: var(--color-white);
    border-color: rgba(255,255,255,0.4);
}

.btn-outline:hover {
    background: rgba(255,255,255,0.1);
    border-color: rgba(255,255,255,0.8);
}

.btn-full {
    width: 100%;
}

/* ============================
   HEADER / NAVIGATION
   ============================ */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(250,250,247,0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid transparent;
    transition: all var(--transition-base);
}

header.scrolled {
    background: rgba(250,250,247,0.95);
    border-bottom-color: var(--color-border);
    box-shadow: var(--shadow-sm);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 76px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.65rem;
    color: var(--color-primary);
    z-index: 1001;
}

.logo-icon {
    color: var(--color-primary);
}

.logo span {
    font-family: var(--font-display);
    font-size: 1.35rem;
    font-weight: 400;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 2.25rem;
}

.nav-links a {
    font-size: 0.88rem;
    font-weight: 500;
    color: var(--color-text-secondary);
    position: relative;
    padding: 0.25rem 0;
}

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

.nav-links a:hover {
    color: var(--color-primary);
}

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

.nav-cta {
    background: var(--color-primary) !important;
    color: var(--color-white) !important;
    padding: 0.6rem 1.4rem !important;
    border-radius: var(--radius-sm);
    font-weight: 600 !important;
}

.nav-cta::after { display: none !important; }

.nav-cta:hover {
    background: var(--color-primary-light) !important;
    transform: translateY(-1px);
}

/* Mobile Toggle */
.mobile-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 6px;
    z-index: 1001;
}

.mobile-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-primary);
    transition: all var(--transition-base);
    border-radius: 2px;
}

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

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

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

/* ============================
   HERO SECTION
   ============================ */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    background: var(--color-primary);
    color: var(--color-white);
    overflow: hidden;
    padding-top: 76px;
}

.hero-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
}

.hero-pattern {
    position: absolute;
    inset: 0;
    background-image:
        radial-gradient(circle at 20% 50%, rgba(200,150,90,0.12) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(42,92,71,0.3) 0%, transparent 40%),
        radial-gradient(circle at 60% 80%, rgba(200,150,90,0.08) 0%, transparent 40%);
}

.hero-gradient {
    position: absolute;
    inset: 0;
    background: linear-gradient(165deg, var(--color-primary-dark) 0%, var(--color-primary) 40%, var(--color-primary-light) 100%);
    opacity: 0.9;
}

.hero-inner {
    position: relative;
    z-index: 1;
    text-align: center;
    padding: var(--space-xl) 0;
}

.hero-badge {
    display: inline-block;
    font-size: 0.72rem;
    font-weight: 700;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--color-accent-light);
    border: 1px solid rgba(200,150,90,0.3);
    padding: 0.5rem 1.5rem;
    border-radius: 100px;
    margin-bottom: var(--space-md);
}

.hero h1 {
    max-width: 800px;
    margin: 0 auto var(--space-md);
    color: var(--color-white);
}

.hero h1 em {
    color: var(--color-accent-light);
}

.hero-sub {
    max-width: 580px;
    margin: 0 auto var(--space-lg);
    font-size: 1.1rem;
    line-height: 1.8;
    color: rgba(255,255,255,0.7);
}

.hero-actions {
    display: flex;
    gap: var(--space-sm);
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: var(--space-xl);
}

.hero-stats {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-lg);
    padding-top: var(--space-lg);
    border-top: 1px solid rgba(255,255,255,0.1);
}

.stat { text-align: center; }

.stat-num {
    display: block;
    font-family: var(--font-display);
    font-size: 1.75rem;
    color: var(--color-accent-light);
    margin-bottom: 0.15rem;
}

.stat-label {
    font-size: 0.78rem;
    font-weight: 500;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: rgba(255,255,255,0.5);
}

.stat-divider {
    width: 1px;
    height: 40px;
    background: rgba(255,255,255,0.12);
}

/* ============================
   PRODUCTS SECTION
   ============================ */
.products {
    background: var(--color-surface-warm);
}

.product-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-md);
}

.product-card {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
    border: 1px solid var(--color-border);
}

.product-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}

.product-featured {
    grid-column: span 2;
    display: grid;
    grid-template-columns: 1fr 1fr;
}

.product-visual {
    padding: var(--space-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--color-surface-warm) 0%, var(--color-white) 100%);
    position: relative;
    min-height: 200px;
}

.product-visual::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 50% 50%, var(--accent, var(--color-accent)) 0%, transparent 70%);
    opacity: 0.06;
}

.product-icon {
    width: 90px;
    height: 90px;
    color: var(--accent, var(--color-primary));
}

.product-featured .product-icon {
    width: 110px;
    height: 110px;
}

.product-info {
    padding: var(--space-md) var(--space-md) var(--space-md);
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.product-num {
    font-family: var(--font-display);
    font-size: 2rem;
    color: var(--color-border);
    display: block;
    margin-bottom: 0.25rem;
    line-height: 1;
}

.product-info h3 {
    color: var(--color-primary);
    margin-bottom: 0.5rem;
    font-size: 1.2rem;
}

.product-info p {
    color: var(--color-text-secondary);
    font-size: 0.9rem;
    line-height: 1.65;
}

/* ============================
   SERVICES SECTION
   ============================ */
.services {
    background: var(--color-white);
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-md);
}

.service-card {
    padding: var(--space-lg);
    background: var(--color-surface);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 0;
    background: var(--color-primary);
    transition: height var(--transition-slow);
    border-radius: 0 0 4px 0;
}

.service-card:hover::before {
    height: 100%;
}

.service-card:hover {
    border-color: transparent;
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.service-icon {
    width: 48px;
    height: 48px;
    color: var(--color-primary);
    margin-bottom: var(--space-md);
}

.service-icon svg {
    width: 100%;
    height: 100%;
}

.service-card h3 {
    color: var(--color-primary);
    margin-bottom: 0.75rem;
}

.service-card p {
    color: var(--color-text-secondary);
    font-size: 0.92rem;
    line-height: 1.7;
}

/* ============================
   ABOUT SECTION
   ============================ */
.about {
    background: var(--color-surface-warm);
}

.about-layout {
    display: grid;
    grid-template-columns: 0.9fr 1.1fr;
    gap: var(--space-xl);
    align-items: center;
}

.about-visual {
    display: flex;
    align-items: center;
    justify-content: center;
}

.about-graphic {
    width: 100%;
    max-width: 400px;
    aspect-ratio: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.about-svg {
    width: 100%;
    height: 100%;
    color: var(--color-primary);
}

.about-content .section-tag {
    margin-bottom: var(--space-md);
}

.about-content h2 {
    color: var(--color-primary);
    margin-bottom: var(--space-md);
}

.about-content > p {
    color: var(--color-text-secondary);
    margin-bottom: var(--space-sm);
    font-size: 1rem;
    line-height: 1.8;
}

.about-values {
    margin-top: var(--space-lg);
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.value {
    padding: var(--space-sm) 0;
    border-bottom: 1px solid var(--color-border);
}

.value strong {
    display: block;
    color: var(--color-primary);
    font-size: 0.95rem;
    margin-bottom: 0.15rem;
}

.value span {
    font-size: 0.88rem;
    color: var(--color-text-secondary);
}

/* ============================
   CONTACT SECTION
   ============================ */
.contact {
    background: var(--color-white);
}

.contact-layout {
    display: grid;
    grid-template-columns: 1fr 1.6fr;
    gap: var(--space-xl);
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
}

.info-block h3 {
    color: var(--color-primary);
    margin-bottom: 0.6rem;
    font-size: 1.1rem;
}

.info-block p,
.info-block address {
    color: var(--color-text-secondary);
    font-size: 0.92rem;
    line-height: 1.75;
}

.info-block strong {
    color: var(--color-text);
}

/* Contact Form */
.contact-form-wrap {
    background: var(--color-surface);
    padding: var(--space-lg);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-sm);
}

.form-group {
    margin-bottom: var(--space-md);
}

.form-group label {
    display: block;
    font-size: 0.82rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 0.4rem;
    letter-spacing: 0.02em;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 0.8rem 1rem;
    font-family: var(--font-body);
    font-size: 0.92rem;
    color: var(--color-text);
    background: var(--color-white);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
    outline: none;
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: var(--color-text-muted);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(27,61,47,0.08);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

.form-group select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg width='12' height='8' viewBox='0 0 12 8' fill='none' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M1 1.5L6 6.5L11 1.5' stroke='%236B6B6B' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 1rem center;
    padding-right: 2.5rem;
}

.form-status {
    margin-top: var(--space-sm);
    font-size: 0.88rem;
    font-weight: 500;
    text-align: center;
}

.form-status.success {
    color: var(--color-primary-light);
}

.form-status.error {
    color: #B94A3E;
}

/* ============================
   FOOTER
   ============================ */
footer {
    background: var(--color-primary-dark);
    color: rgba(255,255,255,0.85);
    padding: var(--space-xl) 0 var(--space-lg);
}

.footer-top {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1fr;
    gap: var(--space-lg);
    padding-bottom: var(--space-lg);
    border-bottom: 1px solid rgba(255,255,255,0.08);
}

.footer-logo {
    color: var(--color-white);
}

.footer-logo .logo-icon {
    color: var(--color-white);
}

.footer-tagline {
    margin-top: var(--space-sm);
    color: rgba(255,255,255,0.5);
    font-size: 0.9rem;
    line-height: 1.7;
    max-width: 280px;
}

.footer-nav h4,
.footer-contact h4 {
    color: var(--color-accent-light);
    font-size: 0.78rem;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    margin-bottom: var(--space-sm);
}

.footer-nav ul {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.footer-nav a {
    font-size: 0.88rem;
    color: rgba(255,255,255,0.55);
    transition: color var(--transition-fast);
}

.footer-nav a:hover {
    color: var(--color-white);
}

.footer-contact address,
.footer-contact p {
    font-size: 0.88rem;
    color: rgba(255,255,255,0.55);
    line-height: 1.7;
    margin-bottom: 0.35rem;
}

.footer-bottom {
    padding-top: var(--space-md);
    text-align: center;
}

.footer-bottom p {
    font-size: 0.8rem;
    color: rgba(255,255,255,0.35);
}

/* ============================
   SCROLL ANIMATIONS
   ============================ */
[data-animate] {
    opacity: 0;
    transform: translateY(28px);
    transition: opacity 0.7s cubic-bezier(0.16, 1, 0.3, 1),
                transform 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}

[data-animate].visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============================
   RESPONSIVE
   ============================ */
@media (max-width: 1024px) {
    .product-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .product-featured {
        grid-column: span 2;
    }

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

@media (max-width: 768px) {
    :root {
        --space-2xl: 5rem;
        --space-xl: 3.5rem;
    }

    .mobile-toggle {
        display: flex;
    }

    #main-nav {
        position: fixed;
        inset: 0;
        background: rgba(250,250,247,0.98);
        backdrop-filter: blur(20px);
        -webkit-backdrop-filter: blur(20px);
        display: flex;
        align-items: center;
        justify-content: center;
        opacity: 0;
        visibility: hidden;
        transition: all var(--transition-base);
        z-index: 999;
    }

    #main-nav.open {
        opacity: 1;
        visibility: visible;
    }

    #main-nav .nav-links {
        flex-direction: column;
        gap: var(--space-md);
        text-align: center;
    }

    #main-nav .nav-links a {
        font-size: 1.25rem;
        color: var(--color-primary);
    }

    .nav-cta {
        margin-top: var(--space-sm);
    }

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

    .product-featured {
        grid-column: span 1;
        grid-template-columns: 1fr;
    }

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

    .about-layout {
        grid-template-columns: 1fr;
        gap: var(--space-lg);
    }

    .about-visual {
        order: -1;
    }

    .about-graphic {
        max-width: 260px;
    }

    .contact-layout {
        grid-template-columns: 1fr;
        gap: var(--space-lg);
    }

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

    .hero-stats {
        gap: var(--space-md);
    }

    .hero-actions .btn {
        width: 100%;
    }

    .footer-top {
        grid-template-columns: 1fr;
        gap: var(--space-lg);
    }
}

@media (max-width: 480px) {
    .hero-sub {
        font-size: 1rem;
    }

    .stat-num {
        font-size: 1.35rem;
    }

    .contact-form-wrap {
        padding: var(--space-md);
    }
}