/* General Resets and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    /* Use a single transition property for all elements for consistency */
    transition: all 0.5s ease;
}

:root {
    /* Dark Mode Defaults */
    --background-color: #0d1117;
    --primary-color: #58a6ff;
    --secondary-color: #8b949e;
    --text-color: #ffffff;
    --glass-bg: rgba(255, 255, 255, 0.1);
    --glass-border: rgba(255, 255, 255, 0.2);
    --card-bg: rgba(255, 255, 255, 0.05);
    --card-border: rgba(255, 255, 255, 0.1);
    --btn-bg: #21262d;
    --btn-hover-bg: #30363d;
    --accent-color1: #bb86fc;
    --accent-color2: #03dac6;
    --accent-color3: #ff6347;
    --box-shadow-dark: 0 10px 30px rgba(0, 0, 0, 0.2);
    --box-shadow-light: 0 10px 30px rgba(0, 0, 0, 0.1);
}

/* Light Mode Theme */
.light-mode {
    --background-color: #f8f9fa;
    --primary-color: #007bff;
    --secondary-color: #6c757d;
    --text-color: #343a40;
    --glass-bg: rgba(0, 0, 0, 0.1);
    --glass-border: rgba(0, 0, 0, 0.2);
    --card-bg: #ffffff;
    --card-border: rgba(0, 0, 0, 0);
    --btn-bg: #e9ecef;
    --btn-hover-bg: #ced4da;
    --accent-color1: #6f42c1;
    --accent-color2: #17a2b8;
    --accent-color3: #dc3545;
}

html {
    scroll-behavior: smooth;
    font-size: 16px; /* Base font size for better accessibility */
}

body {
    font-family: 'Poppins', sans-serif;
    color: var(--text-color);
    background-color: var(--background-color);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
    /* Add a subtle background gradient for visual depth */
    background: linear-gradient(135deg, var(--background-color) 0%, #151d27 100%);
}

.light-mode body {
    background: linear-gradient(135deg, var(--background-color) 0%, #e0e0e0 100%);
}

main {
    flex-grow: 1;
}

section {
    padding: 5rem 5%; /* Use rem for consistent spacing */
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
}

h1, h2 {
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: var(--primary-color);
}

h1 {
    font-size: 3.5rem;
}

.section-title {
    font-size: 2.5rem;
    position: relative;
    margin-bottom: 2.5rem;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -0.625rem;
    left: 50%;
    transform: translateX(-50%);
    width: 3.75rem;
    height: 4px;
    background: var(--primary-color);
    border-radius: 2px;
}

p {
    max-width: 44rem;
    margin: 0 auto 1.25rem;
    font-size: 1.1rem;
    color: var(--secondary-color);
}

/* Header & Navigation */
header {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    backdrop-filter: blur(10px);
    background-color: rgba(13, 17, 23, 0.8);
    padding: 1rem 5%;
    border-bottom: 1px solid var(--card-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.light-mode header {
    background-color: rgba(255, 255, 255, 0.8);
}

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

nav a {
    color: var(--secondary-color);
    text-decoration: none;
    font-weight: 400;
    position: relative;
    transition: color 0.3s ease;
}

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

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

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

.toggle-container {
    /* ... (rest of the toggle styles remain the same) ... */
    position: relative;
    width: 50px;
    height: 25px;
}

.toggle-checkbox {
    display: none;
}

.toggle-label {
    display: block;
    width: 100%;
    height: 100%;
    background: var(--btn-bg);
    border: 1px solid var(--card-border);
    border-radius: 25px;
    cursor: pointer;
    position: relative;
    transition: background-color 0.3s ease;
}

.toggle-label::after {
    content: '\f185'; /* Sun icon */
    font-family: "Font Awesome 6 Pro";
    font-weight: 900;
    position: absolute;
    top: 50%;
    left: 5px;
    transform: translateY(-50%);
    font-size: 1rem;
    color: #f39c12;
    transition: left 0.3s ease;
}

.toggle-checkbox:checked + .toggle-label {
    background: var(--btn-bg);
}

.toggle-checkbox:checked + .toggle-label::after {
    content: '\f186'; /* Moon icon */
    font-family: "Font Awesome 6 Pro";
    font-weight: 900;
    left: calc(100% - 20px);
    color: #34495e;
}

/* Buttons and Links */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: 50px;
    background-color: var(--btn-bg);
    backdrop-filter: blur(8px);
    border: 1px solid var(--card-border);
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    margin: 0.625rem;
    transition: all 0.3s ease;
}

.btn:hover,
.btn:focus {
    background-color: var(--btn-hover-bg);
    transform: translateY(-5px) scale(1.05);
    box-shadow: var(--box-shadow-dark);
    color: var(--text-color);
}

.download-btn {
    color: var(--text-color);
    background: var(--accent-color1);
    border-color: var(--accent-color1);
}

.download-btn:hover,
.download-btn:focus {
    box-shadow: 0 0 20px var(--accent-color1);
}

.submit-btn {
    color: var(--text-color);
    background: var(--accent-color2);
    border-color: var(--accent-color2);
}

.submit-btn:hover,
.submit-btn:focus {
    box-shadow: 0 0 20px var(--accent-color2);
}

.social-links a {
    color: var(--secondary-color);
    font-size: 2rem;
    margin: 0 1rem;
    transition: transform 0.3s ease, color 0.3s ease;
}

.social-links a:hover,
.social-links a:focus {
    transform: translateY(-5px) scale(1.1);
    color: var(--primary-color);
}

/* Home Section */
#hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
}

.hero-intro {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 1.25rem;
}

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

.profile-photo {
    width: 12.5rem;
    height: 12.5rem;
    border-radius: 50%;
    object-fit: cover;
    border: 5px solid var(--card-border);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
}

.hero-buttons {
    margin-top: 1.25rem;
}

/* About Section */
#about {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
}

/* Animations */
.animated {
    opacity: 0;
    transform: translateY(20px);
}

.animated.visible {
    animation: fadeInUp 1s ease forwards;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Skills Section */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
    gap: 1.25rem;
    width: 100%;
    max-width: 56.25rem;
    margin-top: 1.875rem;
}

.skill-card {
    background: var(--card-bg);
    backdrop-filter: blur(8px);
    border: 1px solid var(--card-border);
    border-radius: 15px;
    padding: 1.25rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.625rem;
    transition: all 0.3s ease;
}

/* Multicolored cards */
.python-card { border-color: #306998; }
.java-card { border-color: #e06c75; }
.html-card { border-color: #f7581b; }
.css-card { border-color: #264de4; }
.js-card { border-color: #f7df1e; }
.react-card { border-color: #61dafb; }
.node-card { border-color: #3c873a; }
.mysql-card { border-color: #00758f; }
.aiml-card { border-color: #e06c75; }
.git-card { border-color: #f05033; }

.skill-card:hover {
    transform: translateY(-0.625rem) scale(1.05);
    box-shadow: var(--box-shadow-dark);
}

.light-mode .skill-card:hover {
    box-shadow: var(--box-shadow-light);
}

.skill-card i {
    font-size: 3rem;
    color: var(--primary-color);
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.skill-card p {
    font-size: 1rem;
    margin: 0;
    color: var(--text-color);
    opacity: 1;
}

/* Projects Section */
.project-card {
    background: var(--card-bg);
    backdrop-filter: blur(8px);
    border: 1px solid var(--card-border);
    border-radius: 15px;
    padding: 1.875rem;
    margin-bottom: 1.5625rem;
    max-width: 56.25rem;
    width: 100%;
    text-align: left;
    transition: all 0.3s ease;
}

.project-card:hover {
    transform: translateY(-0.3125rem) scale(1.02);
    box-shadow: var(--box-shadow-dark);
}

.project-card h3 {
    font-size: 1.5rem;
    margin-bottom: 0.625rem;
    color: var(--primary-color);
}

.project-card p {
    font-size: 1rem;
    margin-bottom: 0.9375rem;
    color: var(--secondary-color);
}

/* Certifications Section */
.certificate-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); /* auto responsive */
    gap: 15px;
    margin-top: 20px;
}

.certificate-link {
    display: block;
    padding: 12px 15px;
    background-color: var(--card-bg); /* Use a variable for light/dark mode */
    border: 1px solid var(--card-border); /* Use a variable for light/dark mode */
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    text-decoration: none;
    color: var(--text-color); /* Use a variable for light/dark mode */
    font-size: 14px;
    font-weight: 500;
    transition: transform 0.2s ease, box-shadow 0.2s ease, background-color 0.2s ease;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.certificate-link:hover {
    transform: translateY(-3px);
    box-shadow: var(--box-shadow-dark); /* Use a variable for light/dark mode */
    background-color: var(--btn-hover-bg); /* Use a variable for light/dark mode */
    color: var(--primary-color);
}


/* Contact Form */
#contactForm {
    background: var(--card-bg);
    backdrop-filter: blur(8px);
    border: 1px solid var(--card-border);
    border-radius: 15px;
    padding: 1.875rem;
    max-width: 37.5rem;
    width: 100%;
    margin-bottom: 1.875rem;
    text-align: left;
}

.form-group {
    margin-bottom: 1.25rem;
}

.form-group label {
    display: block;
    color: var(--secondary-color);
    margin-bottom: 0.3125rem;
    font-weight: bold;
    opacity: 0.9;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.625rem;
    border: 1px solid var(--card-border);
    border-radius: 8px;
    background-color: var(--btn-bg);
    color: var(--text-color);
    font-family: 'Poppins', sans-serif;
    font-size: 1rem;
}

.form-group textarea {
    resize: vertical;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 5px var(--primary-color);
}

/* Footer */
footer {
    text-align: center;
    padding: 1.25rem 5%;
    background-color: rgb(236, 230, 245);
    border-top: 1px solid var(--card-border);
    color: var(--secondary-color);
    font-size: 0.9rem;
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
    body {
        font-size: 14px;
    }

    h1 {
        font-size: 2.5rem;
    }

    .section-title {
        font-size: 2rem;
    }
    
    .hero-intro {
        flex-direction: column;
        gap: 1.25rem;
    }
    
    .hero-intro h1 {
        margin-top: 1.25rem;
    }

    .hero-buttons {
        display: flex;
        flex-direction: column;
        width: 100%;
        align-items: center;
    }

    .btn {
        width: 80%;
    }

    .section-title::after {
        left: 50%;
        transform: translateX(-50%);
    }

    nav ul {
        flex-wrap: wrap;
        justify-content: center;
        gap: 1rem;
    }
}

@media (max-width: 480px) {
    h1 {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 1.75rem;
    }

    .hero-intro {
        gap: 1rem;
    }
    
    .profile-photo {
        width: 10rem;
        height: 10rem;
    }
}