:root {
    --primary-color: #4a6bff;
    --secondary-color: #f8f9fa;
    --accent-color: #ff6b6b;
    --dark-color: #343a40;
    --light-color: #ffffff;
    --border-radius: 8px;
    --box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background-color: var(--secondary-color);
    color: var(--dark-color);
    line-height: 1.6;
}

header {
    background-color: var(--light-color);
    box-shadow: var(--box-shadow);
    padding: 1rem 2rem;
    position: sticky;
    top: 0;
    z-index: 100;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
}

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

.nav-links {
    display: flex;
    gap: 1.5rem;
}

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

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

.container {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 2rem;
}

.hero {
    text-align: center;
    margin-bottom: 3rem;
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: var(--dark-color);
}

.hero p {
    font-size: 1.1rem;
    color: #666;
    max-width: 700px;
    margin: 0 auto 2rem;
}

.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.tool-card {
    background-color: var(--light-color);
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    padding: 2rem;
    transition: transform 0.3s;
    cursor: pointer;
    text-align: center;
}

.tool-card:hover {
    transform: translateY(-5px);
}

.tool-card i {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.tool-card h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.tool-card p {
    color: #666;
    margin-bottom: 1.5rem;
}

.btn {
    display: inline-block;
    background-color: var(--primary-color);
    color: var(--light-color);
    padding: 0.7rem 1.5rem;
    border-radius: var(--border-radius);
    text-decoration: none;
    font-weight: 500;
    transition: background-color 0.3s;
    border: none;
    cursor: pointer;
}

.btn:hover {
    background-color: #3a5bef;
}

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

.btn-outline:hover {
    background-color: var(--primary-color);
    color: var(--light-color);
}

.tool-section {
    background-color: var(--light-color);
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    padding: 2rem;
    margin-bottom: 3rem;
    display: none;
}

.tool-section.active {
    display: block;
}

.tool-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
}

.tool-header h2 {
    color: var(--primary-color);
}

.back-btn {
    background-color: transparent;
    border: none;
    color: var(--primary-color);
    font-weight: 500;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.file-upload {
    border: 2px dashed #ccc;
    border-radius: var(--border-radius);
    padding: 3rem 2rem;
    text-align: center;
    margin-bottom: 2rem;
    position: relative;
    transition: border-color 0.3s;
}

.file-upload:hover {
    border-color: var(--primary-color);
}

.file-upload input {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    opacity: 0;
    cursor: pointer;
}

.file-upload i {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.file-upload h3 {
    margin-bottom: 0.5rem;
}

.file-upload p {
    color: #666;
}

.file-list {
    margin-bottom: 2rem;
}

.file-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    background-color: var(--secondary-color);
    border-radius: var(--border-radius);
    margin-bottom: 0.5rem;
}

.file-item-info {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.file-icon {
    color: var(--accent-color);
    font-size: 1.5rem;
}

.file-name {
    font-weight: 500;
}

.file-size {
    color: #666;
    font-size: 0.9rem;
}

.remove-file {
    background-color: transparent;
    border: none;
    color: var(--accent-color);
    cursor: pointer;
    font-size: 1.2rem;
}

.options-section {
    margin-bottom: 2rem;
}

.options-section h3 {
    margin-bottom: 1rem;
    color: var(--dark-color);
}

.option-group {
    margin-bottom: 1.5rem;
}

.option-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.option-group select, 
.option-group input[type="range"],
.option-group input[type="number"],
.option-group input[type="text"],
.option-group input[type="color"] {
    width: 100%;
    padding: 0.7rem;
    border: 1px solid #ddd;
    border-radius: var(--border-radius);
    font-size: 1rem;
}

.option-group input[type="range"] {
    padding: 0;
}

.range-value {
    display: inline-block;
    margin-left: 0.5rem;
    font-weight: 500;
}

.checkbox-group {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

.checkbox-group input {
    width: auto;
}

.action-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.preview-container {
    margin-top: 2rem;
    border: 1px solid #ddd;
    border-radius: var(--border-radius);
    padding: 1rem;
    display: none;
}

.preview-container h3 {
    margin-bottom: 1rem;
}

.preview-placeholder {
    background-color: var(--secondary-color);
    height: 300px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: #666;
    border-radius: var(--border-radius);
}

.about-section, .contact-section {
    background-color: var(--light-color);
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    padding: 2rem;
    margin-bottom: 2rem;
}

.about-section h2, .contact-section h2 {
    margin-bottom: 1rem;
    color: var(--primary-color);
}

footer {
    background-color: var(--dark-color);
    color: var(--light-color);
    padding: 2rem;
    text-align: center;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin: 1rem 0;
}

.footer-links a {
    color: var(--light-color);
    text-decoration: none;
}

.footer-links a:hover {
    text-decoration: underline;
}

/* Loading spinner */
.spinner {
    display: none;
    width: 40px;
    height: 40px;
    margin: 0 auto;
    border: 4px solid rgba(0, 0, 0, 0.1);
    border-radius: 50%;
    border-top-color: var(--primary-color);
    animation: spin 1s ease-in-out infinite;
}

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

/* Toast notification */
.toast {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background-color: var(--dark-color);
    color: var(--light-color);
    padding: 1rem 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    transform: translateY(100px);
    opacity: 0;
    transition: all 0.3s ease;
    z-index: 1000;
}

.toast.show {
    transform: translateY(0);
    opacity: 1;
}

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

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

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

    .btn {
        width: 100%;
    }
}