* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
/* 
        change the color style */
        :root {
            --primary-color: #7f70ca;
            --secondary-color: #5a4982;
            --accent-color: #06d6a0;
            --text-light: #f8fafc;
            --text-dark: #080c13;
            --bg-dark: #0f172a;
            --bg-light: #ffffff;
            --glass-bg: rgba(255, 255, 255, 0.1);
            --shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
        }

        body {
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
            background: linear-gradient(135deg, var(--bg-dark) 0%, #1e1b4b 50%, #312e81 100%);
            /* background-color: blue; */
            color: var(--text-light);
            overflow-x: hidden;
            line-height: 1.6;
        }

        /* Animated background particles */
        .bg-animation {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            z-index: -1;
            overflow: hidden;
        }

        .particle {
            position: absolute;
            width: 4px;
            height: 4px;
            background: var(--accent-color);
            border-radius: 50%;
            opacity: 0.6;
            animation: float 8s infinite linear;
        }

        @keyframes float {
            0% {
                transform: translateY(100vh) rotate(0deg);
                opacity: 0;
            }

            10% {
                opacity: 0.6;
            }

            90% {
                opacity: 0.6;
            }

            100% {
                transform: translateY(-100vh) rotate(360deg);
                opacity: 0;
            }
        }

        /* Navigation */
        nav {
            position: fixed;
            top: 0;
            width: 100%;
            background: rgba(15, 23, 42, 0.8);
            backdrop-filter: blur(20px);
            border-bottom: 1px solid rgba(255, 255, 255, 0.1);
            z-index: 1000;
            transition: all 0.3s ease;
        }
#dark-mode-toggle {
            background: none;
            border: none;
            color: var(--text-light);
            font-size: 1.5rem;
            cursor: pointer;
            position: absolute;
            right: 20px;
            top: 15px;
            transition: color 0.3s ease;
        }
        .nav-container {
            max-width: 1200px;
            margin: 0 auto;
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 1rem 2rem;
        }

        .logo {
            font-size: 1.5rem;
            font-weight: 700;
            background: linear-gradient(45deg, var(--primary-color), var(--accent-color));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;

        }



        .nav-links {
            display: flex;
            list-style: none;
            gap: 2rem;
        }

        .nav-links a {
            color: var(--text-light);
            text-decoration: none;
            font-weight: 500;
            transition: all 0.3s ease;
            position: relative;
        }

        .nav-links a:hover {
            color: var(--accent-color);
            transform: translateY(-2px);
        }

        .nav-links a::after {
            content: '';
            position: absolute;
            bottom: -5px;
            left: 0;
            width: 0;
            height: 2px;
            background: var(--accent-color);
            transition: width 0.3s ease;
        }

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

        /* Hero Section */
        /* Extra CSS for Home Section Image and Buttons */

        .hero {
            display: flex;
            justify-content: center;
            align-items: center;
            padding: 60px 20px;
            /* background: linear-gradient(135deg, #0f172a, #064e3b); dark gradient background */
            color: white;
            min-height: 80vh;
            text-align: center;
            flex-direction: column;
            gap: 20px;
        }

        .hero-content {
            max-width: 600px;
            width: 100%;
        }

        .profile-pic {
            width: 180px;
            height: 180px;
            border-radius: 50%;
            object-fit: cover;
            margin: 11px auto 20px auto;
            box-shadow: 0 8px 20px rgba(6, 214, 160, 0.5);
            border: 4px solid #06d6a0;
            transition: transform 0.3s ease;
        }

        .profile-pic:hover {
            transform: scale(1.05);
        }

        .hero h1 {
            font-size: 2.8rem;
            font-weight: 700;
            margin-bottom: 10px;
            font-family: 'Poppins', sans-serif;
        }

        .highlight {
            color: #06d6a0;
        }

        .hero h3 {
            font-weight: 500;
            font-size: 1.3rem;
            margin-bottom: 15px;
            font-family: 'Poppins', sans-serif;
            color: #a3a3a3;
        }

        .hero p {
            font-size: 1.1rem;
            font-weight: 400;
            margin-bottom: 30px;
            color: #cbd5e1;
            font-family: 'Poppins', sans-serif;
        }

        .buttons {
            display: flex;
            justify-content: center;
            gap: 15px;
            flex-wrap: wrap;
        }

        .btn {
            padding: 12px 25px;
            border-radius: 30px;
            font-weight: 600;
            font-size: 1rem;
            text-decoration: none;
            color: white;
            background-color: transparent;
            border: 2px solid white;
            transition: background-color 0.3s ease, color 0.3s ease;
            cursor: pointer;
            font-family: 'Poppins', sans-serif;
        }

        .btn:hover {
            background-color: #06d6a0;
            border-color: #06d6a0;
            color: #0f172a;
        }

        .btn.primary {
            background: linear-gradient(45deg, #06d6a0, #10b981);
            border: none;
        }

        .btn.primary:hover {
            background: linear-gradient(45deg, #10b981, #06d6a0);
            color: white;
        }

        /* Responsive tweaks */
        @media (max-width: 600px) {
            .hero-content {
                padding: 0 10px;
            }

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

            .profile-pic {
                width: 140px;
                height: 140px;
            }

            .buttons {
                flex-direction: column;
                gap: 10px;
            }

            .btn {
                width: 100%;
                text-align: center;
            }
        }

        .cta-buttons {
            display: flex;
            gap: 1rem;
            justify-content: center;
            flex-wrap: wrap;
            opacity: 0;
            transform: translateY(50px);
            animation: fadeInUp 1s ease 0.6s forwards;
        }

        .btn {
            padding: 12px 30px;
            border: none;
            border-radius: 50px;
            font-weight: 600;
            text-decoration: none;
            display: inline-block;
            transition: all 0.3s ease;
            position: relative;
            overflow: hidden;
            cursor: pointer;
        }

        .btn-primary {
            background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
            color: white;
        }

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

        .btn:hover {
            transform: translateY(-3px);
            box-shadow: var(--shadow);
        }

        .btn::before {
            content: '';
            position: absolute;
            top: 0;
            left: -100%;
            width: 100%;
            height: 100%;
            background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
            transition: left 0.5s;
        }

        .btn:hover::before {
            left: 100%;
        }

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

        /* Sections */
        section {
            padding: 5rem 2rem;
            max-width: 1200px;
            margin: 0 auto;
        }

        .section-title {
            text-align: center;
            font-size: 2.5rem;
            margin-bottom: 3rem;
            background: linear-gradient(45deg, var(--primary-color), var(--accent-color));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        /* About Section */
        .about-content {
            display: grid;
            grid-template-columns: 1fr 2fr;
            gap: 3rem;
            align-items: center;
        }

        .about-image {
            position: relative;
        }

        .about-image::before {
            content: '';
            position: absolute;
            top: -20px;
            left: -20px;
            right: 20px;
            bottom: 20px;
            background: linear-gradient(45deg, var(--primary-color), var(--accent-color));
            border-radius: 20px;
            z-index: -1;
        }

        .about-image img {
            width: 100%;
            border-radius: 20px;
            box-shadow: var(--shadow);
        }

        .about-text {
            font-size: 1.1rem;
            line-height: 1.8;
        }

        .skills {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 2rem;
            margin-top: 3rem;
        }

        .skill-card {
            background: var(--glass-bg);
            backdrop-filter: blur(20px);
            border: 1px solid rgba(255, 255, 255, 0.1);
            border-radius: 20px;
            padding: 2rem;
            text-align: center;
            transition: all 0.3s ease;
        }

        .skill-card:hover {
            transform: translateY(-10px);
            box-shadow: var(--shadow);
            border-color: var(--accent-color);
        }

        .skill-icon {
            font-size: 2.5rem;
            margin-bottom: 1rem;
            background: linear-gradient(45deg, var(--primary-color), var(--accent-color));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
/* Filter Buttons */
.project-filters {
    text-align: center;
    margin-bottom: 1.5rem;
}

.filter-btn {
    background: rgba(99, 102, 241, 0.2);
    color: var(--primary-color);
    padding: 0.5rem 1rem;
    margin: 0.3rem;
    border: 1px solid var(--primary-color);
    border-radius: 20px;
    cursor: pointer;
    transition: background 0.3s;
}

.filter-btn:hover,
.filter-btn.active {
    background: var(--primary-color);
    color: white;
}

.project-card {
    transition: opacity 0.3s ease, transform 0.3s ease;
}

.project-card.hide {
    opacity: 0;
    transform: scale(0.9);
    pointer-events: none;
}
/* Add this (simple + reliable). If you already had a .hide rule, keep this too. */
.project-link.hide { display: none; }

        /* Projects Section */
       .projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.project-card {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 20px;
    overflow: hidden;
    transition: all 0.3s ease;
    position: relative;

    display: flex;
    flex-direction: column; /* Stack image & content vertically */
    height: 100%; /* Fill equal height in grid */
    min-height: 420px; /* Ensures consistent card height */
}

.project-card:hover {
    transform: translateY(-10px) scale(1.02);
    box-shadow: var(--shadow);
}

.project-image {
    height: 200px;
    background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
    color: white;
}

.project-content {
    padding: 2rem;
    flex-grow: 1; /* Push footer tags to bottom if space available */
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.project-title {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--accent-color);
}

.project-tech {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 1rem;
}

.tech-tag {
    background: rgba(99, 102, 241, 0.2);
    color: var(--primary-color);
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.8rem;
    border: 1px solid var(--primary-color);
}

.project-image i {
    font-size: 2rem;
    line-height: 1;
}

.project-link {
    text-decoration: none;
    color: white;
    display: block;
}

.project-link:hover,
.project-link:visited {
    color: white;
}


        /* Contact Section */
        .contact-form {
            max-width: 600px;
            margin: 0 auto;
        }

        .form-group {
            margin-bottom: 2rem;
        }

        .form-group label {
            display: block;
            margin-bottom: 0.5rem;
            color: var(--accent-color);
            font-weight: 500;
        }

        .form-group input,
        .form-group textarea {
            width: 100%;
            padding: 1rem;
            background: var(--glass-bg);
            border: 1px solid rgba(255, 255, 255, 0.1);
            border-radius: 10px;
            color: var(--text-light);
            font-family: inherit;
            transition: all 0.3s ease;
        }

        .form-group input:focus,
        .form-group textarea:focus {
            outline: none;
            border-color: var(--accent-color);
            box-shadow: 0 0 0 3px rgba(6, 214, 160, 0.1);
        }

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

        /* Mobile Responsiveness */
        @media (max-width: 768px) {
            .nav-links {
                display: none;
            }

            .about-content {
                grid-template-columns: 1fr;
                text-align: center;
            }

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

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

            .cta-buttons {
                flex-direction: column;
                align-items: center;
            }
        }

        /* Scroll animations */
        .fade-in {
            opacity: 0;
            transform: translateY(50px);
            transition: all 0.8s ease;
        }

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


        /* footer */
        .first-footer {
            background-color: #0f172af2;
            width: 100%;
            height: 60px;
            display: flex;
            justify-content: center;
            align-items: center;
            font-weight: 700;
        }
      
/* back to top     */
#backToTop {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background: var(--primary-color, #6366f1); /* fallback color if --primary-color not set */
    color: white;
    font-size: 1.5rem;
    padding: 10px 15px;
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
    display: none; /* hidden by default */
    transition: opacity 0.3s, transform 0.3s;
    z-index: 999;
}

#backToTop:hover {
    transform: scale(1.1);
    background: var(--secondary-color, #4f46e5);
}
/* chatbot support */
#chatButton {
    position: fixed;
    bottom: 20px;
    left: 20px; /* moved from right to left */
    background: var(--primary-color, #6366f1);
    color: white;
    font-size: 1.8rem;
    padding: 12px 16px;
    border-radius: 50%;
    text-decoration: none;
    box-shadow: 0 4px 10px rgba(0,0,0,0.3);
    transition: transform 0.2s ease, background 0.3s ease;
    z-index: 999;
}

#chatButton:hover {
    transform: scale(1.1);
    background: var(--secondary-color, #4f46e5);
}


/* for light mode */
/* Light Mode Overrides */
body.light-mode {
    background: linear-gradient(135deg, var(--bg-light) 0%, #f1f5f9 50%, #e2e8f0 100%);
    color: var(--text-dark);
}

body.light-mode nav {
    background: rgba(255, 255, 255, 0.8);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

body.light-mode .nav-links a {
    color: var(--text-dark);
}

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

body.light-mode #dark-mode-toggle {
    color: var(--text-dark);
}
/* Light Mode Overrides */
body.light-mode {
    background: linear-gradient(135deg, var(--bg-light) 0%, #f1f5f9 50%, #e2e8f0 100%);
    color: var(--text-dark);
}

/* Navbar in Light Mode (soft blue) */
body.light-mode nav {
    background: #4f46e5; /* light sky blue */
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

body.light-mode .nav-links a {
    color: var(--text-dark);
}

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

body.light-mode #dark-mode-toggle {
    color: var(--text-dark);
}

/* Footer in Light Mode (soft blue tone) */
body.light-mode .first-footer {
    background-color: #4f46e5; /* light blue footer */
    color: var(--text-dark);
}
nav.light-mode .nav-container {
    background: #4f46e5; /* light sky blue */
}


/* Education Section */
#education {
  padding: 5rem 2rem;
  max-width: 1200px;
  margin: 0 auto;
}

.education-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
}

.edu-card {
  background: var(--glass-bg);
  backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 20px;
  padding: 2rem;
  transition: all 0.3s ease;
  box-shadow: var(--shadow);
}

.edu-card:hover {
  transform: translateY(-10px) scale(1.02);
  border-color: var(--accent-color);
  box-shadow: 0 20px 40px rgba(0,0,0,0.3);
}

.edu-card h3 {
  font-size: 1.3rem;
  margin-bottom: 0.5rem;
  background: linear-gradient(45deg, var(--primary-color), var(--accent-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.edu-card p {
  margin-bottom: 0.3rem;
  color: var(--text-light);
  font-size: 1rem;
}

.edu-card span {
  font-size: 0.9rem;
  color: #94a3b8;
}

/* Achievements Section */
#achievements {
  padding: 5rem 2rem;
  max-width: 1200px;
  margin: 0 auto;
}

.achievements-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
}

.achievement-card {
  background: var(--glass-bg);
  backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 20px;
  padding: 2rem;
  transition: all 0.3s ease;
  box-shadow: var(--shadow);
}

.achievement-card:hover {
  transform: translateY(-10px) scale(1.02);
  border-color: var(--accent-color);
  box-shadow: 0 20px 40px rgba(0,0,0,0.3);
}

.achievement-card h3 {
  font-size: 1.3rem;
  margin-bottom: 0.5rem;
  background: linear-gradient(45deg, var(--primary-color), var(--accent-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.achievement-card p {
  margin-bottom: 0.3rem;
  color: var(--text-light);
  font-size: 1rem;
}

.achievement-card span {
  font-size: 0.9rem;
  color: #94a3b8;
}