:root {
    --primary-color: #fe2c55;
    --secondary-color: #25f4ee;
    --dark-color: #121212;
    --light-color: #ffffff;
    --grey-color: #f7f7f7;
    --text-color: #333333;
    --shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    --border-radius: 12px;
    --transition: all 0.3s ease;
}

/* Dark Theme Variables */
.dark-theme {
    --primary-color: #fe2c55;
    --secondary-color: #25f4ee;
    --dark-color: #f7f7f7;
    --light-color: #1e1e1e;
    --grey-color: #2d2d2d;
    --text-color: #f0f0f0;
    --shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
}

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

body {
    font-family: 'Roboto', sans-serif;
    background-color: var(--grey-color);
    color: var(--text-color);
    transition: var(--transition);
    line-height: 1.6;
}

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

/* Header Styles */
header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
    margin-bottom: 30px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo i {
    font-size: 2rem;
    color: var(--primary-color);
}

.logo h1 {
    font-size: 1.8rem;
    font-weight: 700;
    background: linear-gradient(to right, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.theme-toggle {
    cursor: pointer;
    font-size: 1.5rem;
    transition: var(--transition);
}

.theme-toggle:hover {
    transform: scale(1.1);
}

/* Main Content Styles */
main {
    margin-bottom: 50px;
}

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

.intro h2 {
    font-size: 2rem;
    margin-bottom: 10px;
    color: var(--primary-color);
}

.intro p {
    font-size: 1.1rem;
    color: var(--text-color);
    opacity: 0.8;
}

.downloader-box {
    background-color: var(--light-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 30px;
    margin-bottom: 30px;
}

.input-group {
    display: flex;
    margin-bottom: 20px;
}

.input-group input {
    flex: 1;
    padding: 15px 20px;
    border: 2px solid #e0e0e0;
    border-radius: var(--border-radius) 0 0 var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
    background-color: var(--light-color);
    color: var(--text-color);
}

.input-group input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.input-group button {
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 0 25px;
    border-radius: 0 var(--border-radius) var(--border-radius) 0;
    cursor: pointer;
    transition: var(--transition);
}

.input-group button:hover {
    background-color: #e0254d;
}

.options {
    margin-top: 20px;
}

.options h3 {
    font-size: 1.2rem;
    margin-bottom: 15px;
    font-weight: 500;
}

.option-group {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
}

.option {
    display: flex;
    align-items: center;
    gap: 10px;
}

.option input[type="checkbox"] {
    appearance: none;
    -webkit-appearance: none;
    height: 20px;
    width: 20px;
    border-radius: 5px;
    border: 2px solid var(--primary-color);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    outline: none;
    background-color: var(--light-color);
}

.option input[type="checkbox"]:checked {
    background-color: var(--primary-color);
}

.option input[type="checkbox"]:checked::after {
    content: '✓';
    color: white;
    font-size: 14px;
}

.option label {
    cursor: pointer;
    font-size: 1rem;
}

/* Result Box Styles */
.result {
    background-color: var(--light-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 25px;
    margin-bottom: 30px;
    animation: fadeIn 0.5s ease;
}

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

.video-info {
    display: flex;
    flex-direction: column;
    gap: 20px;
    margin-bottom: 25px;
}

.video-preview {
    display: flex;
    align-items: center;
    gap: 20px;
}

.video-preview img {
    width: 120px;
    height: 120px;
    object-fit: cover;
    border-radius: 10px;
}

.video-details h3 {
    font-size: 1.3rem;
    margin-bottom: 5px;
}

.video-details p {
    font-size: 1rem;
    color: var(--text-color);
    opacity: 0.8;
}

.video-stats {
    display: flex;
    gap: 25px;
}

.stat {
    display: flex;
    align-items: center;
    gap: 8px;
}

.stat i {
    color: var(--primary-color);
}

.download-options {
    display: flex;
    gap: 15px;
}

.download-btn {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    padding: 14px 20px;
    background-color: var(--primary-color);
    color: white;
    text-decoration: none;
    border-radius: var(--border-radius);
    font-weight: 500;
    transition: var(--transition);
}

.download-btn:hover {
    opacity: 0.9;
    transform: translateY(-2px);
}

.download-btn.audio {
    background-color: var(--secondary-color);
}

/* Loader Styles */
.loader {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 30px;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 5px solid var(--grey-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 15px;
}

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

/* Error Message Styles */
.error-message {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    background-color: #ffe9e9;
    color: #d32f2f;
    padding: 15px 20px;
    border-radius: var(--border-radius);
    margin-bottom: 30px;
}

.error-message i {
    font-size: 1.5rem;
}

/* Features Section */
.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-bottom: 50px;
}

.feature {
    background-color: var(--light-color);
    padding: 25px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    text-align: center;
    transition: var(--transition);
}

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

.feature i {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 15px;
}

.feature h3 {
    font-size: 1.3rem;
    margin-bottom: 10px;
}

.feature p {
    color: var(--text-color);
    opacity: 0.8;
}

/* How to Use Section */
.how-to {
    background-color: var(--light-color);
    padding: 40px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    margin-bottom: 50px;
}

.how-to h2 {
    text-align: center;
    margin-bottom: 30px;
    font-size: 1.8rem;
    color: var(--primary-color);
}

.steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 25px;
}

.step {
    display: flex;
    align-items: flex-start;
    gap: 15px;
}

.step-number {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background-color: var(--primary-color);
    color: white;
    font-weight: bold;
    border-radius: 50%;
    flex-shrink: 0;
}

.step-content h3 {
    font-size: 1.1rem;
    margin-bottom: 5px;
}

.step-content p {
    font-size: 0.95rem;
    color: var(--text-color);
    opacity: 0.8;
}

/* Footer Styles */
footer {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 15px;
    padding: 30px 0;
    text-align: center;
    border-top: 1px solid rgba(0, 0, 0, 0.1);
}

.footer-links {
    display: flex;
    gap: 20px;
}

.footer-links a {
    color: var(--text-color);
    opacity: 0.7;
    text-decoration: none;
    transition: var(--transition);
}

.footer-links a:hover {
    opacity: 1;
    color: var(--primary-color);
}

/* Responsive Styles */
@media (max-width: 768px) {
    .video-preview {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .download-options {
        flex-direction: column;
    }
    
    .steps {
        grid-template-columns: 1fr;
    }
    
    .option-group {
        flex-direction: column;
        gap: 10px;
    }
}

@media (max-width: 480px) {
    .logo h1 {
        font-size: 1.4rem;
    }
    
    .intro h2 {
        font-size: 1.6rem;
    }
    
    .downloader-box, .result, .how-to {
        padding: 20px;
    }
    
    .feature {
        padding: 20px 15px;
    }
}