:root {
    /* Dark Theme (Default) */
    --bg-color: #121212;
    --bg-secondary: #1e1e1e;
    --text-color: #e0e0e0;
    --text-secondary: #a0a0a0;
    --accent-color: #4a8fff;
    --accent-hover: #3a7fee;
    --border-color: #333333;
    --card-bg: #1a1a1a;
    --input-bg: #2a2a2a;
    --shadow-color: rgba(0, 0, 0, 0.2);
}

[data-theme="light"] {
    /* Light Theme */
    --bg-color: #f5f5f5;
    --bg-secondary: #ffffff;
    --text-color: #333333;
    --text-secondary: #666666;
    --accent-color: #4a8fff;
    --accent-hover: #3a7fee;
    --border-color: #dddddd;
    --card-bg: #ffffff;
    --input-bg: #f0f0f0;
    --shadow-color: rgba(0, 0, 0, 0.1);
}

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

body {
    font-family: 'Poppins', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    transition: background-color 0.3s, color 0.3s;
}

a {
    color: var(--accent-color);
    text-decoration: none;
    transition: color 0.3s;
}

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

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.center-content {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
}

/* Preloader */
#preloader {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: var(--bg-color);
    z-index: 9999;
    display: flex;
    justify-content: center;
    align-items: center;
}

.loader {
    width: 50px;
    height: 50px;
    border: 5px solid var(--border-color);
    border-top: 5px solid var(--accent-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Header */
.site-header {
    padding: 20px 0;
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    background-color: var(--bg-color);
    z-index: 1000;
    transition: background-color 0.3s;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 24px;
    font-weight: 700;
    color: var(--text-color);
    text-decoration: none;
}

.logo span {
    color: var(--accent-color);
}

.nav-wrapper {
    display: flex;
    align-items: center;
}

.main-navigation {
    margin-right: 20px;
}

.menu-items {
    display: flex;
    list-style: none;
}

.menu-items li {
    margin-left: 20px;
}

.menu-items a {
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s;
}

.menu-items a:hover {
    color: var(--accent-color);
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    color: var(--text-color);
    font-size: 24px;
    cursor: pointer;
}

.overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    z-index: 999;
}

/* Hero Section */
.hero {
    padding: 100px 0;
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 48px;
    margin-bottom: 20px;
    line-height: 1.2;
}

.hero p {
    font-size: 18px;
    margin-bottom: 30px;
    color: var(--text-secondary);
}

.cta-buttons {
    margin-top: 30px;
}

.btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 4px;
    font-weight: 500;
    text-decoration: none;
    transition: all 0.3s;
    margin: 5px;
}

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

.btn-primary:hover {
    background-color: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px var(--shadow-color);
}

.btn-secondary {
    border: 1px solid var(--border-color);
    color: var(--text-color);
}

.btn-secondary:hover {
    background-color: var(--bg-secondary);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px var(--shadow-color);
}

.scroll-indicator {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    animation: bounce 2s infinite;
}

.scroll-indicator a {
    color: var(--text-color);
    opacity: 0.7;
    transition: opacity 0.3s;
}

.scroll-indicator a:hover {
    opacity: 1;
}

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

/* About Section */
.about {
    padding: 80px 0;
    background-color: var(--bg-secondary);
}

.section-title {
    font-size: 32px;
    margin-bottom: 40px;
    text-align: center;
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    width: 50px;
    height: 3px;
    background-color: var(--accent-color);
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
}

.about-content {
    display: flex;
    flex-wrap: wrap;
    gap: 40px;
}

.about-text {
    flex: 1;
    min-width: 300px;
}

.about-text h3 {
    font-size: 24px;
    margin-bottom: 20px;
    color: var(--accent-color);
}

.about-description {
    margin-bottom: 30px;
}

.about-description p {
    margin-bottom: 15px;
}

.skills h4 {
    font-size: 20px;
    margin-bottom: 20px;
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.skill-tag {
    background-color: var(--card-bg);
    color: var(--text-color);
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 14px;
    transition: all 0.3s;
}

.skill-tag:hover {
    background-color: var(--accent-color);
    color: white;
    transform: translateY(-2px);
}

.skill-bars {
    margin-top: 20px;
}

.skill-bar {
    margin-bottom: 20px;
}

.skill-info {
    display: flex;
    justify-content: space-between;
    margin-bottom: 5px;
}

.skill-bar-container {
    height: 10px;
    background-color: var(--card-bg);
    border-radius: 5px;
    overflow: hidden;
}

.skill-progress {
    height: 100%;
    background-color: var(--accent-color);
    border-radius: 5px;
    width: 0;
    transition: width 1s ease-in-out;
}

/* Projects Section */
.projects {
    padding: 80px 0;
}

.projects-filter {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 40px;
}

.filter-btn {
    background: none;
    border: none;
    padding: 8px 16px;
    margin: 5px;
    font-size: 16px;
    color: var(--text-color);
    cursor: pointer;
    transition: all 0.3s;
    border-radius: 4px;
}

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

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

.project-card {
    background-color: var(--card-bg);
    border-radius: 8px;
    overflow: hidden;
    transition: transform 0.3s, box-shadow 0.3s;
}

.project-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 20px var(--shadow-color);
}

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

.project-content {
    padding: 20px;
}

.project-content h3 {
    font-size: 20px;
    margin-bottom: 10px;
}

.project-content p {
    color: var(--text-secondary);
    margin-bottom: 15px;
    font-size: 14px;
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 15px;
}

.project-tag {
    background-color: var(--bg-color);
    color: var(--text-color);
    padding: 4px 10px;
    border-radius: 20px;
    font-size: 12px;
}

.btn-project {
    display: inline-block;
    padding: 8px 16px;
    background-color: var(--accent-color);
    color: white;
    border-radius: 4px;
    font-size: 14px;
    transition: all 0.3s;
}

.btn-project:hover {
    background-color: var(--accent-hover);
    color: white;
}

/* Contact Section */
.contact {
    padding: 80px 0;
    background-color: var(--bg-secondary);
}

.contact-content {
    max-width: 800px;
    margin: 0 auto;
}

.contact-content > p {
    text-align: center;
    margin-bottom: 40px;
}

.contact-info {
    margin-bottom: 40px;
    text-align: center;
}

.contact-info p {
    margin-bottom: 10px;
}

.contact-form {
    background-color: var(--card-bg);
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 5px 15px var(--shadow-color);
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
}

.form-control {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background-color: var(--input-bg);
    color: var(--text-color);
    transition: border-color 0.3s;
}

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

.btn-submit {
    display: inline-block;
    padding: 12px 30px;
    background-color: var(--accent-color);
    color: white;
    border: none;
    border-radius: 4px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s;
}

.btn-submit:hover {
    background-color: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px var(--shadow-color);
}

.alert {
    padding: 15px;
    border-radius: 4px;
    margin-bottom: 20px;
}

.alert-success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.alert-danger {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

/* Footer */
.site-footer {
    padding: 40px 0;
    text-align: center;
    border-top: 1px solid var(--border-color);
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-bottom: 20px;
}

.social-links a {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background-color: var(--bg-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-color);
    transition: all 0.3s;
}

.social-links a:hover {
    background-color: var(--accent-color);
    color: white;
    transform: translateY(-3px);
}

.copyright {
    font-size: 14px;
    color: var(--text-secondary);
}

/* Back to Top Button */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 40px;
    height: 40px;
    background-color: var(--accent-color);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s;
    z-index: 99;
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background-color: var(--accent-hover);
    transform: translateY(-5px);
}

/* Project Single Page */
.project-single {
    padding: 80px 0;
}

.project-article {
    max-width: 800px;
    margin: 0 auto;
}

.project-header {
    margin-bottom: 30px;
}

.project-title {
    font-size: 36px;
    margin-bottom: 15px;
}

.project-categories {
    margin-bottom: 20px;
}

.project-category {
    background-color: var(--accent-color);
    color: white;
    padding: 5px 10px;
    border-radius: 4px;
    font-size: 14px;
}

.project-featured-image {
    margin-bottom: 30px;
    border-radius: 8px;
    overflow: hidden;
}

.project-featured-image img {
    width: 100%;
    height: auto;
}

.project-content {
    margin-bottom: 40px;
    line-height: 1.8;
}

.project-content p {
    margin-bottom: 20px;
}

.project-content h2, .project-content h3 {
    margin-top: 30px;
    margin-bottom: 15px;
}

.project-content ul, .project-content ol {
    margin-bottom: 20px;
    padding-left: 20px;
}

.project-content li {
    margin-bottom: 10px;
}

.project-meta {
    margin-bottom: 40px;
    padding: 20px;
    background-color: var(--card-bg);
    border-radius: 8px;
}

.project-tags h3 {
    font-size: 18px;
    margin-bottom: 15px;
}

.tags-list {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 20px;
}

.project-link {
    margin-top: 20px;
}

.project-navigation {
    display: flex;
    justify-content: space-between;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
}

.nav-previous, .nav-next {
    max-width: 45%;
}

.nav-previous a, .nav-next a {
    display: flex;
    align-items: center;
    color: var(--text-color);
    transition: color 0.3s;
}

.nav-previous a:hover, .nav-next a:hover {
    color: var(--accent-color);
}

.nav-previous i {
    margin-right: 10px;
}

.nav-next i {
    margin-left: 10px;
}

/* Discount Calculator Page */
.discount-page {
    padding: 80px 0;
}

.page-title {
    font-size: 36px;
    margin-bottom: 15px;
    text-align: center;
}

.page-definition {
    text-align: center;
    margin-bottom: 40px;
    color: var(--text-secondary);
    font-weight: normal;
}

.calculator {
    max-width: 600px;
    margin: 0 auto;
    background-color: var(--card-bg);
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 5px 15px var(--shadow-color);
}

.calculator h2 {
    text-align: center;
    margin-bottom: 30px;
}

.discount-inputs {
    margin-bottom: 30px;
}

.input-group {
    margin-bottom: 15px;
}

.input-group input {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background-color: var(--input-bg);
    color: var(--text-color);
}

.extra-discount {
    display: none;
    opacity: 0;
    transform: translateY(-10px);
    transition: opacity 0.4s, transform 0.4s;
}

.extra-discount.active {
    opacity: 1;
    transform: translateY(0);
}

.add-discount-btn {
    background: none;
    border: none;
    color: var(--accent-color);
    cursor: pointer;
    display: flex;
    align-items: center;
    margin-bottom: 20px;
}

.add-discount-btn i {
    margin-left: 5px;
}

.discount-summary {
    background-color: var(--bg-color);
    padding: 10px;
    border-radius: 4px;
    margin-bottom: 20px;
    text-align: center;
    display: none;
}

.calculator button {
    display: block;
    width: 100%;
    padding: 12px;
    background-color: var(--accent-color);
    color: white;
    border: none;
    border-radius: 4px;
    font-weight: 500;
    cursor: pointer;
    transition: background-color 0.3s;
}

.calculator button:hover {
    background-color: var(--accent-hover);
}

.result {
    margin-top: 20px;
    padding: 15px;
    background-color: var(--bg-color);
    border-radius: 4px;
    text-align: center;
    display: none;
}

.discount-info {
    margin-top: 40px;
}

.discount-info h3 {
    margin-bottom: 15px;
}

.tip-box {
    background-color: var(--bg-color);
    padding: 15px;
    border-radius: 4px;
    margin-top: 20px;
}

.tip-box h4 {
    margin-bottom: 10px;
    color: var(--accent-color);
}

/* QR Code Generator Page */
.qr-tool-container {
    padding: 80px 0;
}

.qr-header {
    text-align: center;
    margin-bottom: 40px;
}

.qr-description {
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto 20px;
}

.browser-support {
    background-color: #fff3cd;
    color: #856404;
    padding: 10px;
    border-radius: 4px;
    margin-bottom: 20px;
    text-align: center;
}

.message {
    padding: 15px;
    border-radius: 4px;
    margin-bottom: 20px;
    text-align: center;
}

.error-message {
    background-color: #f8d7da;
    color: #721c24;
}

.qr-form {
    max-width: 600px;
    margin: 0 auto 40px;
}

.qr-settings {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    margin-top: 15px;
}

.qr-setting-group {
    flex: 1;
    min-width: 200px;
}

.qr-setting-group label {
    display: block;
    margin-bottom: 8px;
}

.qr-setting-group select {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background-color: var(--input-bg);
    color: var(--text-color);
}

.qr-result {
    max-width: 600px;
    margin: 0 auto 40px;
    background-color: var(--card-bg);
    padding: 30px;
    border-radius: 8px;
    text-align: center;
}

.qr-result h3 {
    margin-bottom: 20px;
}

.qr-image-container {
    margin-bottom: 20px;
}

.qr-image-container img {
    max-width: 200px;
    height: auto;
    margin-bottom: 15px;
}

.qr-info {
    background-color: var(--bg-color);
    padding: 10px;
    border-radius: 4px;
    font-size: 14px;
    margin-top: 15px;
}

.qr-actions {
    display: flex;
    justify-content: center;
    gap: 10px;
}

.qr-btn {
    display: inline-flex;
    align-items: center;
    padding: 10px 20px;
    background-color: var(--accent-color);
    color: white;
    border-radius: 4px;
    transition: all 0.3s;
}

.qr-btn i {
    margin-right: 8px;
}

.qr-btn:hover {
    background-color: var(--accent-hover);
    color: white;
}

.qr-btn-secondary {
    background-color: var(--bg-color);
    color: var(--text-color);
}

.qr-btn-secondary:hover {
    background-color: var(--border-color);
    color: var(--text-color);
}

.qr-templates {
    margin-bottom: 60px;
}

.qr-templates-title {
    text-align: center;
    margin-bottom: 30px;
}

.qr-templates-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
}

.qr-template-card {
    background-color: var(--card-bg);
    padding: 20px;
    border-radius: 8px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s;
}

.qr-template-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px var(--shadow-color);
}

.qr-template-icon {
    font-size: 24px;
    color: var(--accent-color);
    margin-bottom: 15px;
}

.qr-template-card h3 {
    margin-bottom: 10px;
}

.qr-template-card p {
    font-size: 14px;
    color: var(--text-secondary);
}

.qr-help {
    max-width: 800px;
    margin: 0 auto;
}

.qr-help-title {
    text-align: center;
    margin-bottom: 30px;
}

.qr-help-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 30px;
}

.qr-help-item {
    text-align: center;
}

.qr-help-item h3 {
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.qr-help-item h3 i {
    margin-right: 10px;
    color: var(--accent-color);
}

.qr-help-item p {
    font-size: 14px;
    color: var(--text-secondary);
}

/* Animations */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

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

/* 404 Page */
.error-404 {
    padding: 100px 0;
    text-align: center;
}

.error-content {
    max-width: 600px;
    margin: 0 auto;
}

.error-404 .page-title {
    font-size: 120px;
    margin-bottom: 0;
    color: var(--accent-color);
}

.error-404 .page-subtitle {
    font-size: 36px;
    margin-bottom: 20px;
}

.error-404 p {
    margin-bottom: 30px;
    color: var(--text-secondary);
}

.error-actions {
    margin-top: 30px;
}