/*
===========================================
MODERN SOFTWARE ENGINEER PORTFOLIO
Professional Design by GitHub Copilot
===========================================
*/

/* ===== ROOT VARIABLES ===== */
:root {
    --primary-color: #0066FF;
    --secondary-color: #00D4FF;
    --accent-color: #FF6B35;
    --dark-bg: #0F1419;
    --light-bg: #F5F7FA;
    --text-dark: #1A1A1A;
    --text-light: #666666;
    --text-muted: #999999;
    --border-color: #E0E0E0;
    --success-color: #00C896;
    --warning-color: #FFB81C;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.15);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.2);
    --transition: all 0.3s ease;
}

/* ===== BASE STYLES ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    color: var(--text-dark);
    background-color: #ffffff;
    line-height: 1.6;
    overflow-x: hidden;
}

/* ===== PRELOADER ===== */
.preloader {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 99999;
    display: flex;
    flex-flow: row nowrap;
    justify-content: center;
    align-items: center;
    background: #ffffff;
}

.spinner {
    border: 1px solid transparent;
    border-radius: 5px;
    position: relative;
}

.spinner:before {
    content: '';
    box-sizing: border-box;
    position: absolute;
    top: 50%;
    left: 50%;
    width: 40px;
    height: 40px;
    margin-top: -20px;
    margin-left: -20px;
    border-radius: 50%;
    border: 3px solid transparent;
    border-top-color: var(--primary-color);
    border-right-color: var(--secondary-color);
    animation: spinner 0.8s linear infinite;
}

@keyframes spinner {
    to { transform: rotate(360deg); }
}

/* ===== TYPOGRAPHY ===== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: 1rem;
}

h1 {
    font-size: 3rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}

h2 {
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: -0.01em;
}

h3 {
    font-size: 1.75rem;
    font-weight: 600;
}

h4 {
    font-size: 1.25rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    font-size: 0.85rem;
}

p {
    color: var(--text-light);
    font-size: 1rem;
    line-height: 1.8;
    margin-bottom: 1rem;
}

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

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

strong {
    font-weight: 600;
    color: var(--text-dark);
}

/* ===== BUTTONS ===== */
.btn-modern {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 32px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.95rem;
    letter-spacing: 0.5px;
    text-transform: uppercase;
    border: 2px solid transparent;
    cursor: pointer;
    transition: var(--transition);
    gap: 8px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: #ffffff;
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(0, 102, 255, 0.4);
}

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

.btn-secondary:hover {
    background: var(--primary-color);
    color: #ffffff;
    transform: translateY(-2px);
}

/* ===== NAVIGATION ===== */
.custom-navbar {
    background-color: #ffffff;
    padding: 0;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
    border-bottom: 1px solid var(--border-color);
    transition: var(--transition);
}

.custom-navbar.top-nav-collapse {
    box-shadow: var(--shadow-md);
    padding: 8px 0;
}

.navbar-brand {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--primary-color) !important;
    text-shadow: none !important;
    letter-spacing: 0.5px;
    margin-right: 2rem;
}

.logo-icon {
    color: var(--secondary-color);
    margin: 0 4px;
}

.navbar-nav > li > a {
    color: var(--text-light) !important;
    font-size: 0.9rem;
    font-weight: 500;
    letter-spacing: 0.5px;
    text-transform: uppercase;
    transition: var(--transition);
    position: relative;
    margin: 0 8px;
}

.navbar-nav > li > a:before {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -5px;
    left: 0;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    transition: width 0.3s ease;
}

.navbar-nav > li > a:hover:before,
.navbar-nav > li.active > a:before {
    width: 100%;
}

.navbar-nav > li > a:hover,
.navbar-nav > li.active > a {
    color: var(--primary-color) !important;
}

.navbar-toggle {
    border: none;
    padding: 5px 10px;
}

.navbar-toggle .icon-bar {
    background: var(--primary-color);
    border-color: transparent;
    height: 3px;
}

/* ===== SECTION STYLES ===== */
section {
    padding: 80px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-header h2 {
    position: relative;
    display: inline-block;
    margin-bottom: 20px;
}

.section-header.light h2 {
    color: #ffffff;
}

.divider {
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    margin: 0 auto;
    border-radius: 2px;
}

/* ===== HERO SECTION ===== */
.hero-section {
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, #ffffff 0%, var(--light-bg) 100%);
    position: relative;
    overflow: hidden;
    padding: 120px 0 80px;
}

.stars {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    overflow: hidden;
}

.stars:before,
.stars:after {
    content: '';
    position: absolute;
    width: 2px;
    height: 2px;
    background: var(--primary-color);
    box-shadow: 0 0 0 0 var(--secondary-color);
    border-radius: 50%;
    animation: twinkle 3s infinite;
}

@keyframes twinkle {
    0%, 100% { opacity: 0.3; }
    50% { opacity: 1; }
}

.hero-content {
    display: flex;
    align-items: center;
    gap: 40px;
}

.hero-text {
    z-index: 2;
}

.hero-box {
    position: relative;
}

.hero-box h4 {
    color: var(--primary-color);
    margin-bottom: 10px;
    font-size: 0.85rem;
}

.hero-box h1 {
    color: var(--text-dark);
    font-size: 3.5rem;
    margin-bottom: 20px;
    line-height: 1.2;
}

.highlight {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-box > p:first-of-type {
    font-size: 1.2rem;
    color: var(--text-light);
    font-weight: 500;
    margin-bottom: 15px;
}

.hero-description {
    color: var(--text-light);
    font-size: 1rem;
    max-width: 500px;
}

.hero-buttons {
    display: flex;
    gap: 15px;
    margin-top: 30px;
    flex-wrap: wrap;
}

.hero-buttons .btn-modern {
    font-size: 0.85rem;
    padding: 14px 28px;
}

.hero-image {
    position: relative;
}

.image-wrapper {
    position: relative;
    width: 100%;
    height: 500px;
    border-radius: 20px;
    overflow: hidden;
    box-shadow: var(--shadow-lg);
}

.hero-img {
    background: url('../images/home-img.jpg') center/cover no-repeat;
    width: 100%;
    height: 100%;
    transition: transform 0.3s ease;
}

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

.scroll-indicator {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 1;
}

.scroll-indicator span {
    display: block;
    width: 3px;
    height: 20px;
    background: var(--primary-color);
    border-radius: 2px;
    animation: scroll-down 2s infinite;
}

@keyframes scroll-down {
    0%, 20%, 50%, 80%, 100% { transform: translateY(0); }
    40% { transform: translateY(10px); }
    60% { transform: translateY(5px); }
}

/* ===== ABOUT SECTION ===== */
.about-section {
    background-color: #ffffff;
    padding: 80px 0;
}

.about-section .row {
    align-items: center;
}

.about-image {
    position: relative;
    height: 450px;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    margin-bottom: 30px;
}

.about-img {
    background: url('../images/about-img.jpg') center/cover no-repeat;
    width: 100%;
    height: 100%;
}

.about-content h3 {
    color: var(--text-dark);
    margin-bottom: 20px;
    font-size: 2rem;
}

.about-content p {
    margin-bottom: 20px;
    line-height: 1.8;
}

.about-stats {
    display: flex;
    gap: 40px;
    margin-top: 40px;
    padding-top: 30px;
    border-top: 2px solid var(--border-color);
}

.stat {
    text-align: center;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    color: var(--text-light);
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-top: 5px;
}

/* ===== SKILLS SECTION ===== */
.skills-section {
    background-color: var(--light-bg);
    padding: 80px 0;
}

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

.skill-category {
    background: #ffffff;
    padding: 30px;
    border-radius: 12px;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.skill-category:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-md);
    border-color: var(--primary-color);
}

.category-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 20px;
}

.category-header i {
    font-size: 1.8rem;
    color: var(--primary-color);
    background: rgba(0, 102, 255, 0.1);
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 10px;
}

.category-header h4 {
    margin: 0;
    font-size: 1.1rem;
}

.skills-list {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.skill-badge {
    display: inline-block;
    background: linear-gradient(135deg, rgba(0, 102, 255, 0.1), rgba(0, 212, 255, 0.1));
    color: var(--primary-color);
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
    border: 1px solid var(--primary-color);
    transition: var(--transition);
}

.skill-badge:hover {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: #ffffff;
    border-color: transparent;
    transform: scale(1.05);
}

/* ===== EXPERIENCE SECTION ===== */
.experience-section {
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    padding: 80px 0;
}

.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
}

.timeline:before {
    content: '';
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 3px;
    height: 100%;
    background: linear-gradient(180deg, var(--primary-color), var(--secondary-color));
}

.timeline-item {
    margin-bottom: 50px;
    position: relative;
}

.timeline-item:nth-child(odd) .timeline-content {
    margin-left: 0;
    margin-right: auto;
    width: 48%;
    text-align: right;
    padding-right: 30px;
}

.timeline-item:nth-child(even) .timeline-content {
    margin-left: auto;
    margin-right: 0;
    width: 48%;
    padding-left: 30px;
}

.timeline-marker {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 16px;
    height: 16px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 50%;
    top: 0;
    box-shadow: 0 0 0 8px rgba(0, 102, 255, 0.2);
}

.timeline-content {
    background: rgba(255, 255, 255, 0.05);
    padding: 25px;
    border-radius: 10px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    transition: var(--transition);
}

.timeline-content:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: var(--primary-color);
}

.experience-header {
    margin-bottom: 15px;
}

.experience-header h3 {
    color: #ffffff;
    margin-bottom: 8px;
}

.company-badge {
    display: inline-block;
    background: rgba(0, 102, 255, 0.2);
    color: var(--secondary-color);
    padding: 4px 12px;
    border-radius: 4px;
    font-size: 0.8rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.timeline-date,
.location {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.9rem;
    margin: 4px 0;
}

.timeline-date i,
.location i {
    margin-right: 6px;
    color: var(--secondary-color);
}

.experience-description {
    text-align: left;
    color: rgba(255, 255, 255, 0.8);
}

.experience-description p {
    color: rgba(255, 255, 255, 0.9);
    margin: 12px 0;
    font-size: 0.95rem;
    font-weight: 500;
}

.experience-description ul {
    margin: 12px 0 12px 20px;
    padding-left: 0;
}

.experience-description li {
    color: rgba(255, 255, 255, 0.8);
    margin: 8px 0;
    list-style: circle;
    font-size: 0.95rem;
}

.experience-link {
    color: var(--secondary-color);
    font-weight: 600;
    text-decoration: underline;
}

/* ===== EDUCATION SECTION ===== */
.education-section {
    background-color: #ffffff;
    padding: 80px 0;
}

.education-card {
    background: linear-gradient(135deg, rgba(0, 102, 255, 0.05), rgba(0, 212, 255, 0.05));
    padding: 40px;
    border-radius: 15px;
    border: 2px solid var(--border-color);
    text-align: center;
    transition: var(--transition);
    height: 100%;
}

.education-card:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-md);
    transform: translateY(-8px);
}

.education-icon {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 20px;
}

.education-card h3 {
    color: var(--text-dark);
    margin-bottom: 10px;
}

.education-university {
    color: var(--primary-color);
    font-weight: 600;
    font-size: 1rem;
    margin-bottom: 10px;
}

.education-period {
    color: var(--text-light);
    font-size: 0.95rem;
    margin-bottom: 15px;
    font-weight: 500;
}

.education-details {
    color: var(--text-light);
    font-size: 0.95rem;
    line-height: 1.6;
}

/* ===== REFERENCES SECTION ===== */
.references-section {
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    padding: 80px 0;
}

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

.reference-card {
    background: rgba(255, 255, 255, 0.05);
    padding: 30px;
    border-radius: 12px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    transition: var(--transition);
    text-align: center;
}

.reference-card:hover {
    border-color: var(--primary-color);
    background: rgba(255, 255, 255, 0.08);
    transform: translateY(-8px);
}

.reference-header h4 {
    color: #ffffff;
    margin-bottom: 5px;
    font-size: 1.1rem;
    text-transform: none;
}

.reference-title {
    color: var(--secondary-color);
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 15px;
}

.reference-bio {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.95rem;
    margin-bottom: 20px;
}

.reference-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(0, 102, 255, 0.2);
    color: var(--secondary-color);
    padding: 10px 20px;
    border-radius: 6px;
    transition: var(--transition);
    font-weight: 600;
}

.reference-link:hover {
    background: rgba(0, 102, 255, 0.3);
    transform: translateX(5px);
}

/* ===== CONTACT SECTION ===== */
.contact-section {
    background-color: #ffffff;
    padding: 80px 0;
}

.contact-info-block h3,
.social-links h3 {
    color: var(--text-dark);
    margin-bottom: 30px;
    font-size: 1.8rem;
}

.contact-item {
    display: flex;
    gap: 20px;
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
}

.contact-item:last-child {
    border-bottom: none;
}

.contact-icon {
    flex-shrink: 0;
}

.contact-icon i {
    font-size: 1.8rem;
    color: var(--primary-color);
    background: rgba(0, 102, 255, 0.1);
    width: 60px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 12px;
}

.contact-details h4 {
    color: var(--text-dark);
    margin-bottom: 8px;
    text-transform: none;
    font-weight: 600;
    font-size: 1rem;
}

.contact-details p {
    color: var(--text-light);
    margin: 0;
}

.contact-details a {
    color: var(--primary-color);
    font-weight: 600;
}

.contact-details a:hover {
    color: var(--secondary-color);
}

.social-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 15px;
}

.social-link {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 10px;
    padding: 20px;
    border: 2px solid var(--border-color);
    border-radius: 10px;
    transition: var(--transition);
    text-decoration: none !important;
}

.social-link i {
    font-size: 1.8rem;
}

.social-link span {
    font-size: 0.9rem;
    font-weight: 600;
}

.social-link.linkedin {
    color: #0077B5;
}

.social-link.github {
    color: #333;
}

.social-link.stackoverflow {
    color: #F48024;
}

.social-link.medium {
    color: #000;
}

.social-link.instagram {
    color: #E4405F;
}

.social-link:hover {
    border-color: currentColor;
    background: rgba(0, 0, 0, 0.03);
    transform: translateY(-5px);
}

/* ===== FOOTER ===== */
.footer-section {
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    color: rgba(255, 255, 255, 0.7);
    text-align: center;
    padding: 30px 0;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-section p {
    margin: 0;
    font-size: 0.95rem;
}

.heart {
    display: inline-block;
    animation: pulse 1.5s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.2); }
}

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 992px) {
    h1 {
        font-size: 2.5rem;
    }

    h2 {
        font-size: 2rem;
    }

    .hero-box h1 {
        font-size: 2.5rem;
    }

    .hero-buttons {
        flex-direction: column;
    }

    .timeline:before {
        left: 10px;
    }

    .timeline-item:nth-child(odd) .timeline-content,
    .timeline-item:nth-child(even) .timeline-content {
        width: 100%;
        margin: 0;
        padding-left: 60px;
        text-align: left;
    }

    .timeline-marker {
        left: 0;
    }

    .about-stats {
        flex-wrap: wrap;
        gap: 20px;
    }
}

@media (max-width: 768px) {
    section {
        padding: 60px 0;
    }

    .section-header {
        margin-bottom: 40px;
    }

    h1 {
        font-size: 2rem;
    }

    h2 {
        font-size: 1.8rem;
    }

    .hero-section {
        padding: 100px 0 40px;
    }

    .hero-content {
        flex-direction: column;
        gap: 30px;
    }

    .hero-box h1 {
        font-size: 2rem;
    }

    .hero-image {
        width: 100%;
    }

    .image-wrapper {
        height: 300px;
    }

    .navbar-brand {
        font-size: 1.1rem;
    }

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

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

    .about-stats {
        justify-content: space-around;
    }

    .contact-info-block,
    .social-links {
        margin-bottom: 40px;
    }
}

@media (max-width: 480px) {
    body {
        font-size: 14px;
    }

    h1 {
        font-size: 1.8rem;
    }

    h2 {
        font-size: 1.5rem;
    }

    h3 {
        font-size: 1.3rem;
    }

    section {
        padding: 40px 0;
    }

    .hero-box h1 {
        font-size: 1.6rem;
    }

    .hero-description {
        font-size: 0.95rem;
    }

    .hero-buttons {
        flex-direction: column;
    }

    .btn-modern {
        width: 100%;
    }

    .timeline-content {
        padding: 20px;
    }

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

    .contact-item {
        flex-direction: column;
        gap: 15px;
    }

    .contact-icon i {
        font-size: 1.5rem;
        width: 50px;
        height: 50px;
    }
}

/* ===== UTILITIES ===== */
.container-fluid {
    max-width: 1400px;
    margin: 0 auto;
}

.wow {
    visibility: hidden;
}

.wow.animated {
    visibility: visible;
}