/* ============================================
   PORTFOLIO WEBSITE - MAIN STYLESHEET
   Design: Cloud Architect (Modern Minimalist with Glassmorphism)
   Author: Shakil Md. Rezwanul Bari Portfolio
   ============================================ */

/* ============================================
   1. ROOT VARIABLES & RESET
   ============================================ */

:root {
    /* Colors */
    --color-white: #FAFAFA;
    --color-teal: #0891B2;
    --color-teal-dark: #0E7490;
    --color-gray-light: #E5E7EB;
    --color-gray-medium: #D1D5DB;
    --color-gray-dark: #6B7280;
    --color-slate: #1F2937;
    --color-slate-light: #374151;
    --color-slate-dark: #111827;
    --color-green: #10B981;
    --color-orange: #F97316;
    --color-purple: #7C3AED;
    
    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #7C3AED 0%, #0891B2 100%);
    --gradient-secondary: linear-gradient(135deg, #0891B2 0%, #06B6D4 100%);
    
    /* Typography */
    --font-primary: 'Poppins', sans-serif;
    --font-secondary: 'Inter', sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    --spacing-4xl: 6rem;
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    
    /* 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), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    
    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-base: 0.3s ease;
    --transition-slow: 0.5s ease;
}

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

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

body {
    font-family: var(--font-secondary);
    color: var(--color-slate);
    background-color: var(--color-white);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ============================================
   2. CONTAINER & LAYOUT
   ============================================ */

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

/* ============================================
   3. NAVIGATION
   ============================================ */

.navbar {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(250, 250, 250, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    box-shadow: var(--shadow-sm);
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-lg) var(--spacing-xl);
    height: 70px;
}

.nav-brand {
    flex-shrink: 0;
}

.logo {
    font-family: var(--font-primary);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-teal);
    text-decoration: none;
    transition: color var(--transition-base);
}

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

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-2xl);
    margin: 0;
    padding: 0;
}

.nav-link {
    font-family: var(--font-primary);
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--color-slate);
    text-decoration: none;
    position: relative;
    transition: color var(--transition-base);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-teal);
    transition: width var(--transition-base);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

.nav-link:hover,
.nav-link.active {
    color: var(--color-teal);
}

.hamburger {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    gap: 5px;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--color-slate);
    border-radius: 2px;
    transition: all var(--transition-base);
}

/* ============================================
   4. HERO SECTION
   ============================================ */

.hero {
    padding: var(--spacing-4xl) 0;
    background: linear-gradient(135deg, rgba(250, 250, 250, 0.5) 0%, rgba(8, 145, 178, 0.05) 100%);
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-4xl);
    align-items: center;
}

.hero-text h1 {
    font-family: var(--font-primary);
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1.2;
    color: var(--color-slate-dark);
    margin-bottom: var(--spacing-lg);
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-title {
    font-size: 3rem;
    margin-bottom: var(--spacing-md);
}

.hero-subtitle {
    font-family: var(--font-primary);
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--color-teal);
    margin-bottom: var(--spacing-lg);
}

.hero-description {
    font-size: 1.1rem;
    color: var(--color-gray-dark);
    margin-bottom: var(--spacing-2xl);
    line-height: 1.8;
}

.hero-cta {
    display: flex;
    gap: var(--spacing-lg);
    flex-wrap: wrap;
}

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

.hero-image {
    width: 100%;
    aspect-ratio: 1;
    border-radius: var(--radius-xl);
    background: var(--gradient-secondary);
    box-shadow: var(--shadow-xl);
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0px);
    }
    50% {
        transform: translateY(-20px);
    }
}

/* ============================================
   5. BUTTONS
   ============================================ */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.75rem;
    border-radius: var(--radius-lg);
    font-family: var(--font-primary);
    font-weight: 600;
    font-size: 1rem;
    text-decoration: none;
    border: none;
    cursor: pointer;
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.3);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn:hover::before {
    width: 300px;
    height: 300px;
}

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

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

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

.btn-secondary:hover {
    background: rgba(8, 145, 178, 0.1);
    transform: translateY(-2px);
}

.btn-large {
    padding: 1rem 2.5rem;
    font-size: 1.1rem;
}

/* ============================================
   6. STATS SECTION
   ============================================ */

.stats {
    padding: var(--spacing-4xl) 0;
    background: var(--color-white);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-2xl);
}

.stat-card {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(0, 0, 0, 0.1);
    border-radius: var(--radius-lg);
    padding: var(--spacing-2xl);
    text-align: center;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-md);
}

.stat-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--color-teal);
}

.stat-number {
    font-family: var(--font-primary);
    font-size: 2.5rem;
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: var(--spacing-md);
}

.stat-label {
    font-size: 1rem;
    color: var(--color-gray-dark);
    font-weight: 500;
}

/* ============================================
   7. SECTION STYLING
   ============================================ */

section {
    padding: var(--spacing-4xl) 0;
}

.section-title {
    font-family: var(--font-primary);
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--color-slate-dark);
    margin-bottom: var(--spacing-2xl);
    text-align: center;
}

.section-subtitle {
    font-size: 1.1rem;
    color: var(--color-gray-dark);
    text-align: center;
    margin-bottom: var(--spacing-2xl);
}

/* ============================================
   8. EXPERTISE SECTION
   ============================================ */

.expertise {
    background: linear-gradient(135deg, rgba(250, 250, 250, 0.5) 0%, rgba(8, 145, 178, 0.03) 100%);
}

.expertise-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-2xl);
}

.expertise-card {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(0, 0, 0, 0.1);
    border-radius: var(--radius-lg);
    padding: var(--spacing-2xl);
    transition: all var(--transition-base);
    box-shadow: var(--shadow-md);
}

.expertise-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--color-teal);
}

.expertise-icon {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-lg);
}

.expertise-card h3 {
    font-family: var(--font-primary);
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--color-slate-dark);
    margin-bottom: var(--spacing-md);
}

.expertise-card p {
    color: var(--color-gray-dark);
    line-height: 1.7;
}

/* ============================================
   9. FEATURED PROJECTS SECTION
   ============================================ */

.featured-projects {
    background: var(--color-white);
}

.projects-preview {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: var(--spacing-2xl);
    margin-bottom: var(--spacing-3xl);
}

.project-preview-card {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(0, 0, 0, 0.1);
    border-radius: var(--radius-lg);
    padding: var(--spacing-2xl);
    transition: all var(--transition-base);
    box-shadow: var(--shadow-md);
    position: relative;
    overflow: hidden;
}

.project-preview-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transition: left 0.5s ease;
}

.project-preview-card:hover::before {
    left: 100%;
}

.project-preview-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--color-teal);
}

.project-badge {
    display: inline-block;
    background: rgba(8, 145, 178, 0.1);
    color: var(--color-teal);
    padding: 0.5rem 1rem;
    border-radius: 999px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
}

.project-preview-card h3 {
    font-family: var(--font-primary);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-slate-dark);
    margin-bottom: var(--spacing-md);
}

.project-preview-card p {
    color: var(--color-gray-dark);
    margin-bottom: var(--spacing-lg);
    line-height: 1.7;
}

.project-tags {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.tag {
    display: inline-block;
    background: rgba(8, 145, 178, 0.15);
    color: var(--color-teal);
    padding: 0.35rem 0.85rem;
    border-radius: 999px;
    font-size: 0.8rem;
    font-weight: 500;
}

.view-all {
    text-align: center;
}

/* ============================================
   10. CERTIFICATIONS SECTION
   ============================================ */

.certifications-highlight {
    background: linear-gradient(135deg, rgba(250, 250, 250, 0.5) 0%, rgba(8, 145, 178, 0.03) 100%);
}

.certifications-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-3xl);
}

.cert-badge {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(10px);
    border: 2px solid var(--color-teal);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    text-align: center;
    font-family: var(--font-primary);
    font-weight: 600;
    color: var(--color-teal);
    transition: all var(--transition-base);
    box-shadow: var(--shadow-sm);
}

.cert-badge:hover {
    background: var(--color-teal);
    color: white;
    transform: scale(1.05);
    box-shadow: var(--shadow-lg);
}

/* ============================================
   11. CTA SECTION
   ============================================ */

.cta-section {
    background: var(--gradient-primary);
    color: white;
    text-align: center;
    padding: var(--spacing-4xl) 0;
}

.cta-section h2 {
    font-family: var(--font-primary);
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-lg);
}

.cta-section p {
    font-size: 1.1rem;
    margin-bottom: var(--spacing-2xl);
    opacity: 0.95;
}

/* ============================================
   12. FOOTER
   ============================================ */

.footer {
    background: var(--color-slate-dark);
    color: white;
    padding: var(--spacing-3xl) 0 var(--spacing-lg);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-2xl);
    margin-bottom: var(--spacing-2xl);
}

.footer-section h4 {
    font-family: var(--font-primary);
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
}

.footer-section p {
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: var(--spacing-md);
}

.footer-section ul {
    list-style: none;
    padding: 0;
}

.footer-section ul li {
    margin-bottom: var(--spacing-sm);
}

.footer-section a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: color var(--transition-base);
}

.footer-section a:hover {
    color: var(--color-teal);
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: var(--spacing-lg);
    text-align: center;
    color: rgba(255, 255, 255, 0.6);
}

/* ============================================
   13. ANIMATIONS & TRANSITIONS
   ============================================ */

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

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

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

.fade-in-up {
    animation: fadeInUp 0.8s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
}

.slide-in-left {
    animation: slideInLeft 0.8s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
}

.slide-in-right {
    animation: slideInRight 0.8s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
}

/* ============================================
   14. UTILITY CLASSES
   ============================================ */

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

.text-muted {
    color: var(--color-gray-dark);
}

.mt-lg {
    margin-top: var(--spacing-2xl);
}

.mb-lg {
    margin-bottom: var(--spacing-2xl);
}

.py-lg {
    padding-top: var(--spacing-2xl);
    padding-bottom: var(--spacing-2xl);
}