/* Base Styles */
:root {
    --primary-color: #0066ff;
    --primary-rgb: 0, 102, 255;
    --secondary-color: #4f46e5;
    --accent-color: #6366f1;
    --background-color: #ffffff;
    --text-color: #333;
    --text-light: #6b7280;
    --card-bg: #ffffff;
    --nav-bg: rgba(255, 255, 255, 0.95);
    --footer-bg: #1f2937;
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    --gradient-primary: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    
    /* Responsive Font Sizes */
    --font-size-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
    --font-size-sm: clamp(0.875rem, 0.8rem + 0.375vw, 1rem);
    --font-size-base: clamp(1rem, 0.9rem + 0.5vw, 1.125rem);
    --font-size-lg: clamp(1.125rem, 1rem + 0.625vw, 1.25rem);
    --font-size-xl: clamp(1.25rem, 1.1rem + 0.75vw, 1.5rem);
    --font-size-2xl: clamp(1.5rem, 1.3rem + 1vw, 2rem);
    --font-size-3xl: clamp(2rem, 1.8rem + 1.25vw, 2.5rem);
    
    /* Spacing Variables */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 3rem;
    --spacing-xl: 4rem;
    
    /* Container Max Width */
    --container-max-width: min(1200px, 90%);
}

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

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

body {
    font-family: 'Inter', sans-serif;
    color: var(--text-color);
    line-height: 1.6;
    background-color: #f8fafc;
    overflow-x: hidden;
}

/* Container */
.container {
    width: min(90%, var(--container-max-width));
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* Sections */
.section {
    padding: var(--spacing-xl) 0;
    margin-top: var(--spacing-lg);
}

/* Cards */
.card {
    background: var(--card-bg);
    border-radius: 8px;
    padding: var(--spacing-md);
    box-shadow: var(--shadow-md);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

/* Responsive Grid Layouts */
.grid-2, .grid-3, .grid-4 {
    display: grid;
    gap: var(--spacing-md);
}

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

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: 6px;
    font-weight: 500;
    text-decoration: none;
    transition: all 0.3s ease;
}

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

.btn-secondary {
    background: rgba(var(--primary-rgb), 0.1);
    color: var(--primary-color);
}

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

/* Form Styles */
.form-group {
    margin-bottom: var(--spacing-md);
}

.form-control {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #e2e8f0;
    border-radius: 6px;
    font-size: var(--font-size-base);
    transition: border-color 0.3s ease;
}

.form-control:focus {
    border-color: var(--primary-color);
    outline: none;
}

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

.timeline-item {
    margin-bottom: var(--spacing-xl);
    position: relative;
    padding-left: var(--spacing-xl);
}

.timeline-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    height: 100%;
    width: 2px;
    background: var(--primary-color);
}

/* Project Cards */
.project-card {
    position: relative;
    overflow: hidden;
    border-radius: 8px;
}

.project-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.project-content {
    padding: var(--spacing-md);
}

/* Responsive Design */
@media (max-width: 1200px) {
    :root {
        --container-max-width: 1140px;
    }
    
    .grid-4 {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 992px) {
    :root {
        --container-max-width: 960px;
    }
    
    .grid-3, .grid-4 {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .timeline {
        padding: 0 var(--spacing-md);
    }
}

@media (max-width: 768px) {
    :root {
        --container-max-width: 720px;
        --spacing-xl: 3rem;
        --spacing-lg: 2rem;
    }
    
    .grid-2, .grid-3, .grid-4 {
        grid-template-columns: 1fr;
    }
    
    .section {
        padding: var(--spacing-lg) 0;
        margin-top: var(--spacing-md);
    }
    
    .hero-section {
        padding: var(--spacing-xl) 0;
    }
    
    .hero-title {
        font-size: var(--font-size-2xl);
    }
    
    .hero-subtitle {
        font-size: var(--font-size-lg);
    }
    
    .hero-buttons {
        flex-direction: column;
        gap: var(--spacing-sm);
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
    
    .timeline-item {
        padding-left: var(--spacing-lg);
    }
}

@media (max-width: 576px) {
    :root {
        --container-max-width: 540px;
        --spacing-md: 1.5rem;
        --spacing-sm: 0.75rem;
    }
    
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .card {
        padding: var(--spacing-sm);
    }
    
    .section-title {
        font-size: var(--font-size-xl);
        margin-bottom: var(--spacing-lg);
    }
    
    .nav-logo {
        font-size: var(--font-size-lg);
    }
    
    .project-image {
        height: 160px;
    }
    
    .form-control {
        padding: 0.5rem;
    }
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--nav-bg);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 1rem;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: #007bff;
    text-decoration: none;
}

.nav-logo i {
    color: #007bff;
}

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

.nav-link {
    color: var(--text-color);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

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

.mobile-nav-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
    position: relative;
    z-index: 2000;
}

.mobile-nav-toggle span {
    display: block;
    width: 25px;
    height: 2px;
    background-color: #007bff;
    margin: 5px auto;
    transition: all 0.3s ease-in-out;
}

@media (max-width: 768px) {
    .mobile-nav-toggle {
        display: block;
        margin-right: 1rem;
    }

    .nav-links {
        position: fixed;
        inset: 0 0 0 30%;
        background: var(--background-color);
        padding: min(30vh, 10rem) 2rem;
        flex-direction: column;
        gap: 2rem;
        transform: translateX(100%);
        transition: transform 0.3s ease-out;
        z-index: 1000;
        text-align: center;
        align-items: center;
        justify-content: center;
    }

    .nav-link {
        font-size: var(--font-size-lg);
        width: 100%;
        text-align: center;
        padding: 0.75rem 0;
    }

    .nav-links[data-visible="true"] {
        transform: translateX(0%);
        box-shadow: -5px 0 15px rgba(0, 0, 0, 0.1);
    }

    .mobile-nav-toggle[aria-expanded="true"] span {
        background-color: #007bff;
    }

    .mobile-nav-toggle[aria-expanded="true"] span:nth-child(1) {
        transform: translateY(7px) rotate(45deg);
    }

    .mobile-nav-toggle[aria-expanded="true"] span:nth-child(2) {
        opacity: 0;
    }

    .mobile-nav-toggle[aria-expanded="true"] span:nth-child(3) {
        transform: translateY(-7px) rotate(-45deg);
    }

    /* About page mobile responsiveness */
    .about-section {
        padding: 6rem 1rem 3rem;
    }

    .about-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

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

    .about-image {
        max-width: 80%;
        margin: 0 auto;
    }

    .about-image::after {
        display: none;
    }

    .skills-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
        padding: 0 1rem;
    }

    .skill-category {
        padding: 1.5rem;
    }

    .progress-container {
        margin-bottom: 1.5rem;
    }

    .social-links {
        display: flex;
        flex-direction: column;
        gap: 1rem;
        align-items: center;
    }

    .social-links .btn {
        width: 100%;
        max-width: 200px;
        margin: 0 !important;
    }
}

/* Sections */
.section {
    padding: var(--spacing-xl) 0;
    margin-top: var(--spacing-xl);
}

.section-title {
    text-align: center;
    margin-bottom: var(--spacing-xl);
    font-size: var(--font-size-2xl);
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

/* Cards */
.card {
    background: var(--card-bg);
    border-radius: 16px;
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

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

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

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

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

/* Footer */
.footer {
    background: var(--footer-bg);
    color: white;
    padding: var(--spacing-xl) 0 var(--spacing-lg);
}

.footer-container {
    width: min(90%, var(--container-max-width));
    margin: 0 auto;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.footer-section h3 {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-md);
    color: white;
}

.footer-section p {
    color: #e2e8f0;
    margin-bottom: var(--spacing-md);
    font-size: var(--font-size-sm);
}

.footer-section span {
    color: #e2e8f0;
    text-decoration: none;
    font-size: var(--font-size-sm);
    transition: color 0.3s ease;
}

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

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

.footer-links a {
    color: #e2e8f0;
    text-decoration: none;
    font-size: var(--font-size-sm);
    transition: color 0.3s ease;
}

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

.social-links {
    display: flex;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-md);
}

.social-link {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    text-decoration: none;
    transition: all 0.3s ease;
    font-size: var(--font-size-base);
}

.social-link:hover {
    background: var(--primary-color);
    transform: translateY(-3px);
}

.footer-bottom {
    padding-top: var(--spacing-md);
    text-align: center;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    font-size: var(--font-size-sm);
    color: #e2e8f0;
}

@media (max-width: 992px) {
    .footer-content {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-lg);
    }
}

@media (max-width: 576px) {
    .footer-content {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
        text-align: center;
    }

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

    .footer-section {
        margin-bottom: var(--spacing-lg);
    }
}

/* Responsive Design */
@media (max-width: 1200px) {
    .grid-4 {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 992px) {
    .grid-3, .grid-4 {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-content {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-lg);
    }
}

@media (max-width: 768px) {
    /* Grids */
    .grid-2 {
        grid-template-columns: 1fr;
    }

    /* Section Spacing */
    .section {
        padding: var(--spacing-lg) 0;
        margin-top: var(--spacing-lg);
    }

    /* Typography */
    .section-title {
        margin-bottom: var(--spacing-lg);
    }
}

@media (max-width: 576px) {
    /* Grid */
    .grid-3, .grid-4 {
        grid-template-columns: 1fr;
    }

    /* Footer */
    .footer-content {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }

    /* Spacing */
    .container {
        padding: 0 var(--spacing-sm);
    }

    /* Typography */
    h1 {
        font-size: var(--font-size-2xl);
    }

    h2 {
        font-size: var(--font-size-xl);
    }

    h3 {
        font-size: var(--font-size-lg);
    }
}

/* Animation Classes */
.fade-up {
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.6s ease;
}

.fade-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.hidden {
    display: none;
}

.visible {
    display: block;
}

/* Form Elements */
.form-group {
    margin-bottom: var(--spacing-md);
}

.form-label {
    display: block;
    margin-bottom: var(--spacing-xs);
    font-weight: 500;
}

.form-control {
    width: 100%;
    padding: var(--spacing-sm);
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: var(--font-size-base);
    transition: all 0.3s ease;
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: 8px;
    font-weight: 500;
    text-decoration: none;
    transition: all 0.3s ease;
    cursor: pointer;
    font-size: var(--font-size-sm);
}

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    border: none;
}

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

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

/* Responsive Images */
img {
    max-width: 100%;
    height: auto;
}

/* Progress Bars */
.progress-container {
    margin-bottom: var(--spacing-md);
}

.progress-bar {
    height: 8px;
    background: #e2e8f0;
    border-radius: 4px;
    overflow: hidden;
}

.progress {
    height: 100%;
    background: var(--gradient-primary);
    border-radius: 4px;
    transition: width 1s ease;
}

/* Project Cards */
.project-card {
    position: relative;
    overflow: hidden;
    border-radius: 16px;
    background: var(--background-color);
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
}

.project-card:hover {
    transform: translateY(-5px) scale(1.02);
    box-shadow: var(--shadow-lg);
}

.project-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.project-card:hover img {
    transform: scale(1.1);
}

.project-content {
    padding: var(--spacing-md);
}

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

.project-tag {
    background: rgba(37, 99, 235, 0.1);
    color: var(--primary-color);
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: var(--font-size-xs);
    transition: all 0.3s ease;
}

.project-tag:hover {
    background: var(--primary-color);
    color: white;
}

/* Education Timeline Cards */
.timeline-card {
    background: var(--background-color);
    border-radius: 16px;
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
    border-left: 4px solid var(--primary-color);
}

.timeline-card:hover {
    transform: translateX(10px);
    box-shadow: var(--shadow-lg);
}

/* Skill Cards */
.skill-card {
    background: var(--background-color);
    border-radius: 16px;
    padding: var(--spacing-md);
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
}

.skill-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    background: var(--gradient-primary);
    color: white;
}

.skill-card:hover .skill-icon {
    color: white;
}

.skill-icon {
    font-size: var(--font-size-2xl);
    color: var(--primary-color);
    margin-bottom: var(--spacing-sm);
    transition: all 0.3s ease;
}

/* Certificate Cards */
.certificate-card {
    background: var(--background-color);
    border-radius: 16px;
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.certificate-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.certificate-icon {
    font-size: var(--font-size-2xl);
    color: var(--primary-color);
    background: rgba(37, 99, 235, 0.1);
    padding: var(--spacing-sm);
    border-radius: 12px;
    transition: all 0.3s ease;
}

.certificate-card:hover .certificate-icon {
    background: var(--primary-color);
    color: white;
    transform: rotate(360deg);
}

/* Responsive Grid Layouts */
.grid {
    display: grid;
    gap: var(--spacing-lg);
}

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

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

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

@media (max-width: 1200px) {
    .grid-4 {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 992px) {
    .grid-3, .grid-4 {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .grid-2, .grid-3, .grid-4 {
        grid-template-columns: 1fr;
    }
    
    .certificate-card {
        flex-direction: column;
        text-align: center;
    }
}

/* Animation Classes */
.fade-up {
    opacity: 0;
    transform: translateY(20px);
    animation: fadeUp 0.5s ease forwards;
}

@keyframes fadeUp {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}