/**
 * Sentra Aplikasi - Main Stylesheet
 * Modern, minimalist, professional design
 * Mobile-first responsive approach
 */

/* ============================================
   CSS VARIABLES - INDUSTRIAL THEME
   ============================================ */
:root {
    /* Colors - Premium Modern Palette */
    --color-primary: #09090B;
    --color-secondary: #18181B;
    --color-accent: #2563EB;
    --color-dark: #050507;
    --color-light: #F5F5F5;
    --color-white: #FFFFFF;
    --color-gray-100: #F8F9FA;
    --color-gray-200: #E8EAED;
    --color-gray-300: #DADCE0;
    --color-gray-400: #BDC1C6;
    --color-gray-500: #9AA0A6;
    --color-gray-600: #80868B;
    --color-gray-700: #5F6368;
    --color-gray-800: #3C4043;
    --color-gray-900: #202124;
    
    /* Status Colors - Industrial */
    --color-success: #10B981;
    --color-warning: #F59E0B;
    --color-danger: #EF4444;
    --color-info: #3B82F6;
    
    /* Premium Accents */
    --color-steel: #6B7280;
    --color-iron: #4B5563;
    --color-zinc: #71717A;
    --color-copper: #1D4ED8;
    
    /* Typography */
    --font-primary: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-heading: 'Segoe UI', system-ui, sans-serif;
    --font-mono: 'Courier New', monospace;
    
    /* Font Sizes */
    --text-xs: 0.75rem;
    --text-sm: 0.875rem;
    --text-base: 1rem;
    --text-lg: 1.125rem;
    --text-xl: 1.25rem;
    --text-2xl: 1.5rem;
    --text-3xl: 1.875rem;
    --text-4xl: 2.25rem;
    --text-5xl: 3rem;
    
    /* Spacing */
    --spacing-1: 0.25rem;
    --spacing-2: 0.5rem;
    --spacing-3: 0.75rem;
    --spacing-4: 1rem;
    --spacing-5: 1.25rem;
    --spacing-6: 1.5rem;
    --spacing-8: 2rem;
    --spacing-10: 2.5rem;
    --spacing-12: 3rem;
    --spacing-16: 4rem;
    --spacing-20: 5rem;
    
    /* Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.375rem;
    --radius-lg: 0.5rem;
    --radius-xl: 0.75rem;
    --radius-2xl: 1rem;
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    
    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-base: 300ms ease-in-out;
    --transition-slow: 500ms ease-in-out;
    
    /* Max Width */
    --max-width-sm: 640px;
    --max-width-md: 768px;
    --max-width-lg: 1024px;
    --max-width-xl: 1280px;
    --max-width-2xl: 1536px;
}

/* ============================================
   RESET & BASE STYLES
   ============================================ */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-primary);
    font-size: var(--text-base);
    line-height: 1.6;
    color: var(--color-gray-900);
    background-color: #FAFAFA;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ============================================
   TYPOGRAPHY
   ============================================ */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 600;
    line-height: 1.2;
    color: var(--color-dark);
    margin-bottom: var(--spacing-4);
}

h1 { font-size: var(--text-4xl); }
h2 { font-size: var(--text-3xl); }
h3 { font-size: var(--text-2xl); }
h4 { font-size: var(--text-xl); }
h5 { font-size: var(--text-lg); }
h6 { font-size: var(--text-base); }

p {
    margin-bottom: var(--spacing-4);
}

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

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

/* ============================================
   LAYOUT
   ============================================ */
.container {
    width: 100%;
    max-width: var(--max-width-xl);
    margin: 0 auto;
    padding: 0 var(--spacing-4);
}

.container-sm { max-width: var(--max-width-sm); }
.container-md { max-width: var(--max-width-md); }
.container-lg { max-width: var(--max-width-lg); }
.container-xl { max-width: var(--max-width-xl); }

.section {
    padding: var(--spacing-20) 0;
}

.section-sm { padding: var(--spacing-12) 0; }
.section-lg { padding: var(--spacing-20) 0; }

.section-title {
    text-align: center;
    margin-bottom: var(--spacing-12);
}

.section-title h2 {
    font-size: var(--text-4xl);
    font-weight: 700;
    margin-bottom: var(--spacing-6);
    color: var(--color-dark);
    position: relative;
    padding-bottom: var(--spacing-4);
}

.section-title h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: var(--color-accent);
    border-radius: 2px;
}

.section-title p {
    font-size: var(--text-lg);
    color: var(--color-gray-600);
    max-width: 600px;
    margin: 0 auto;
}

/* Grid System */
.grid {
    display: grid;
    gap: var(--spacing-6);
}

.grid-cols-1 { grid-template-columns: repeat(1, 1fr); }
.grid-cols-2 { grid-template-columns: repeat(2, 1fr); }
.grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
.grid-cols-4 { grid-template-columns: repeat(4, 1fr); }

/* Flexbox Utilities */
.flex {
    display: flex;
}

.flex-col {
    flex-direction: column;
}

.items-center {
    align-items: center;
}

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

.justify-between {
    justify-content: space-between;
}

.gap-2 { gap: var(--spacing-2); }
.gap-4 { gap: var(--spacing-4); }
.gap-6 { gap: var(--spacing-6); }
.gap-8 { gap: var(--spacing-8); }

/* ============================================
   HEADER & NAVIGATION
   ============================================ */
.header {
    background: var(--color-primary);
    border-bottom: 2px solid var(--color-accent);
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
}

.navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-3) 0;
    gap: var(--spacing-6);
}

.logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-size: var(--text-lg);
    font-weight: 700;
    color: var(--color-white);
    letter-spacing: 0.5px;
    text-transform: uppercase;
    text-decoration: none;
    flex-shrink: 0;
}

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

.logo::after {
    display: none;
}

.nav-menu {
    display: flex;
    list-style: none;
    align-items: center;
    gap: var(--spacing-6);
    margin: 0;
    padding: 0;
}

.nav-link {
    color: var(--color-gray-300);
    font-weight: 500;
    font-size: var(--text-sm);
    transition: all var(--transition-fast);
    padding-bottom: 2px;
    border-bottom: 2px solid transparent;
    white-space: nowrap;
}

.nav-link:hover {
    color: var(--color-white);
    border-bottom-color: var(--color-accent);
}

.nav-link.active {
    color: var(--color-accent);
    border-bottom-color: var(--color-accent);
}

.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-2);
    color: var(--color-white);
}

.mobile-menu-toggle svg {
    stroke: var(--color-white);
}

/* ============================================
   HERO SECTION
   ============================================ */
.hero {
    background: linear-gradient(135deg, #18181B 0%, #09090B 100%);
    padding: var(--spacing-20) 0;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: repeating-linear-gradient(
        90deg,
        transparent 0px,
        rgba(230, 126, 34, 0.03) 1px,
        transparent 2px,
        transparent 40px
    );
    z-index: 0;
}

.hero-title {
    font-size: var(--text-5xl);
    color: var(--color-white);
    margin-bottom: var(--spacing-6);
    line-height: 1.1;
    position: relative;
    z-index: 1;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.hero-subtitle {
    font-size: var(--text-xl);
    color: var(--color-gray-300);
    margin-bottom: var(--spacing-8);
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
    position: relative;
    z-index: 1;
}

.hero-actions {
    display: flex;
    gap: var(--spacing-4);
    justify-content: center;
    align-items: center;
    position: relative;
    z-index: 1;
}

/* ============================================
   SECTIONS
   ============================================ */
.section {
    padding: var(--spacing-16) 0;
}

.section.bg-light {
    background: var(--color-gray-100);
}

.section-title {
    text-align: center;
    margin-bottom: var(--spacing-12);
}

.section-title h2 {
    font-size: var(--text-3xl);
    font-weight: 600;
    color: var(--color-dark);
    margin-bottom: var(--spacing-3);
    position: relative;
    display: inline-block;
    padding-bottom: var(--spacing-4);
}

.section-title h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: var(--color-accent);
    border-radius: 2px;
}

.section-title p {
    font-size: var(--text-lg);
    color: var(--color-gray-600);
    max-width: 700px;
    margin: 0 auto;
}

/* ============================================
   CARDS
   ============================================ */
.card {
    background: var(--color-white);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--radius-lg);
    padding: var(--spacing-6);
    transition: all var(--transition-base);
}

.card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

.card-title {
    font-size: var(--text-xl);
    font-weight: 600;
    margin-bottom: var(--spacing-3);
    color: var(--color-dark);
}

.card-text {
    color: var(--color-gray-600);
    font-size: var(--text-sm);
    line-height: 1.6;
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
    background: var(--color-primary);
    color: var(--color-gray-400);
    padding: var(--spacing-12) 0 var(--spacing-6);
    margin-top: 0;
    border-top: 2px solid var(--color-accent);
    position: relative;
    overflow: hidden;
}

.footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(37, 99, 235, 0.6), transparent);
}

.footer-content {
    display: grid;
    grid-template-columns: 1.6fr 1fr 1fr 1.2fr;
    gap: var(--spacing-10);
    margin-bottom: var(--spacing-8);
    position: relative;
    z-index: 1;
}

.footer-section {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-3);
}

.footer-section h3 {
    color: var(--color-white);
    font-size: var(--text-base);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.6px;
    margin-bottom: var(--spacing-2);
}

.footer-description {
    color: var(--color-gray-400);
    line-height: 1.7;
}

.footer-highlight {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-2);
    padding: var(--spacing-2) var(--spacing-3);
    background: rgba(230, 126, 34, 0.12);
    color: var(--color-accent);
    border-radius: var(--radius-md);
    font-size: var(--text-sm);
    font-weight: 600;
}

.footer-links {
    list-style: none;
    padding: 0;
    margin: 0;
}

.footer-links li + li {
    margin-top: var(--spacing-2);
}

.footer-links a {
    color: var(--color-gray-400);
    transition: color var(--transition-fast);
    font-size: var(--text-sm);
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-2);
}

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

.footer-contact-link {
    color: var(--color-gray-300);
    gap: var(--spacing-3);
}

.footer-contact-link span:last-child {
    line-height: 1.4;
}

.footer-icon {
    width: 36px;
    height: 36px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-md);
    color: var(--color-accent);
}

.footer-icon svg {
    display: block;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    padding-top: var(--spacing-4);
    text-align: center;
    position: relative;
    z-index: 1;
}

.footer-bottom p {
    color: var(--color-gray-500);
    font-size: var(--text-sm);
    margin: 0;
}

/* Language Switcher */
.language-switcher {
    display: inline-flex;
    gap: var(--spacing-1);
    background: rgba(255, 255, 255, 0.05);
    padding: var(--spacing-1);
    border-radius: var(--radius-md);
    border: 1px solid rgba(230, 126, 34, 0.2);
}

.lang-option {
    padding: var(--spacing-2) var(--spacing-3);
    font-size: var(--text-xs);
    font-weight: 600;
    color: var(--color-gray-300);
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    cursor: pointer;
}

.lang-option.active {
    background: var(--color-accent);
    color: var(--color-white);
    box-shadow: 0 2px 4px rgba(230, 126, 34, 0.3);
}

.lang-option:hover:not(.active) {
    color: var(--color-white);
    background: rgba(255, 255, 255, 0.1);
}

/* ============================================
   RESPONSIVE
   ============================================ */
@media (max-width: 768px) {
    .hero-title {
        font-size: var(--text-3xl);
    }
    
    .hero-subtitle {
        font-size: var(--text-lg);
    }
    
    .grid-cols-2,
    .grid-cols-3,
    .grid-cols-4 {
        grid-template-columns: 1fr;
    }
    
    .nav-menu {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background: var(--color-secondary);
        flex-direction: column;
        padding: var(--spacing-4);
        gap: var(--spacing-2);
        box-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
        display: none;
        z-index: 999;
    }
    
    .nav-menu.active {
        display: flex;
    }
    
    .mobile-menu-toggle {
        display: block;
    }
    
    .section {
        padding: var(--spacing-12) 0;
    }
    
    .hero {
        padding: var(--spacing-16) 0;
    }
    
    .hero-actions {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: var(--spacing-6);
    }
    
    .footer-section {
        text-align: left;
    }
    
    .footer-contact-link {
        width: 100%;
        justify-content: flex-start;
    }
    
    .footer-icon {
        width: 32px;
        height: 32px;
    }
    
    .footer {
        padding: var(--spacing-8) 0 var(--spacing-3);
    }
}

/* ============================================
   PRODUCT GRID - LANDING PAGE
   ============================================ */
.product-grid-landing {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-top: 2.5rem;
}

.product-card {
    background: var(--color-white);
    border-radius: var(--radius-xl);
    overflow: hidden;
    transition: all var(--transition-base);
    border: 1px solid var(--color-gray-200);
    box-shadow: var(--shadow-sm);
}

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

.product-card-image {
    position: relative;
    width: 100%;
    aspect-ratio: 16/10;
    overflow: hidden;
    background: var(--color-gray-100);
}

.product-card-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-base);
}

.product-card:hover .product-card-image img {
    transform: scale(1.05);
}

.product-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-gray-400);
}

.product-card-body {
    padding: 1.5rem;
}

.product-card-category {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    background: rgba(230, 126, 34, 0.1);
    color: var(--color-accent);
    border-radius: var(--radius-full);
    font-size: var(--text-xs);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.75rem;
}

.product-card-title {
    font-size: var(--text-lg);
    font-weight: 700;
    color: var(--color-gray-900);
    margin: 0 0 0.75rem 0;
    line-height: 1.4;
    min-height: 2.8rem;
}

.product-card-description {
    font-size: var(--text-sm);
    color: var(--color-gray-600);
    line-height: 1.6;
    margin-bottom: 1.25rem;
    min-height: 3.2rem;
}

.product-card-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: 1rem;
    border-top: 1px solid var(--color-gray-200);
}

.product-card-price {
    font-size: var(--text-xl);
    font-weight: 700;
    color: var(--color-accent);
}

@media (min-width: 769px) and (max-width: 1024px) {
    .grid-cols-3,
    .grid-cols-4 {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .product-grid-landing {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-content {
        grid-template-columns: 1.4fr 1fr;
        gap: var(--spacing-8);
    }
}

@media (max-width: 768px) {
    .product-grid-landing {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
}

/* ============================================
   TESTIMONIALS SECTION
   ============================================ */
.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-top: 2.5rem;
}

.testimonial-card {
    background: var(--color-white);
    border-radius: var(--radius-xl);
    padding: 2rem;
    border: 1px solid var(--color-gray-200);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

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

.testimonial-rating {
    display: flex;
    gap: 0.25rem;
}

.testimonial-rating .star {
    color: var(--color-gray-300);
}

.testimonial-rating .star.filled {
    color: #FBBF24;
}

.testimonial-text {
    font-size: var(--text-base);
    line-height: 1.7;
    color: var(--color-gray-700);
    font-style: italic;
    flex: 1;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--color-gray-200);
}

.author-photo {
    width: 50px;
    height: 50px;
    border-radius: var(--radius-full);
    object-fit: cover;
    flex-shrink: 0;
}

.author-placeholder {
    background: linear-gradient(135deg, var(--color-accent) 0%, var(--color-copper) 100%);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--text-xl);
    font-weight: 700;
}

.author-info {
    flex: 1;
}

.author-name {
    font-weight: 700;
    color: var(--color-gray-900);
    font-size: var(--text-base);
    margin-bottom: 0.25rem;
}

.author-position {
    font-size: var(--text-sm);
    color: var(--color-gray-600);
}

@media (max-width: 1024px) {
    .testimonials-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .testimonials-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .testimonial-card {
        padding: 1.5rem;
    }
}