:root {
    --primary: #1bac91;
    --secondary: 2bb49a;
    --accent: #56cdb7;
    --light: #f8f9fa;
    --dark: #212529;
}

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

body {
    background-color: #f5f7ff;
    color: var(--dark);
    line-height: 1.6;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
header {
    background: white;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

header h1 {
    color: var(--primary);
}

/* Main Converter Section */
.converter-hero {
    text-align: center;
    padding: 3rem 0;
}

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

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

/* Converter Box */
.converter-box {
    background: white;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    padding: 2rem;
    margin-bottom: 3rem;
}

/* Drop Zone */
.drop-zone {
    border: 3px dashed #ddd;
    border-radius: 10px;
    padding: 3rem 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s;
    margin-bottom: 2rem;
    position: relative;
    background: #f9f9f9;
}

.drop-zone:hover {
    border-color: var(--accent);
    background: #f0f5ff;
}

.drop-zone.active {
    border-color: var(--primary);
    background-color: #e6f0ff;
}

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

.file-input {
    display: none;
}

/* Preview Section */
.preview-section {
    display: none;
    margin-bottom: 2rem;
}

.preview-container {
    display: flex;
    gap: 2rem;
    flex-wrap: wrap;
}

.file-info {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: #f5f5f5;
    border-radius: 8px;
    width: 100%;
}

.file-info i {
    font-size: 2.5rem;
    color: var(--primary);
}

.file-info h4 {
    margin-bottom: 0.25rem;
}

/* Conversion Options */
.conversion-options {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.option-card {
    background: white;
    border-radius: 8px;
    padding: 1.5rem;
    box-shadow: 0 3px 10px rgba(0,0,0,0.05);
    border: 2px solid transparent;
    transition: all 0.3s;
}

.option-card.active {
    border-color: var(--primary);
    background: #f0f5ff;
}

.option-card i {
    font-size: 1.5rem;
    color: var(--primary);
    margin-bottom: 0.5rem;
}

/* Quality Control */
.quality-control {
    margin: 2rem 0;
}

.slider-container {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.slider-container select {
    flex: 1;
    padding: 0.5rem;
    border: 1px solid #ddd;
    border-radius: 5px;
}

/* Action Buttons */
.action-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    padding: 0.8rem 1.5rem;
    border-radius: 50px;
    border: none;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

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

.btn-primary:hover {
    background: var(--secondary);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(43, 87, 154, 0.3);
}

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

.btn-outline:hover {
    background: #f0f5ff;
}

/* Features Section */
.features-section {
    padding: 4rem 0;
    background: white;
}

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

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.feature-card {
    padding: 1.5rem;
    border-radius: 10px;
    background: #f9f9f9;
}

.feature-card i {
    font-size: 2rem;
    color: var(--primary);
    margin-bottom: 1rem;
}

/* How It Works */
.how-it-works {
    padding: 4rem 0;
    background: #f5f7ff;
}

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

.step {
    text-align: center;
    padding: 1.5rem;
}

.step-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--primary);
    color: white;
    border-radius: 50%;
    font-weight: bold;
    margin-bottom: 1rem;
}

/* Responsive */
@media (max-width: 768px) {
    .converter-hero h1 {
        font-size: 2rem;
    }
    
    .steps {
        grid-template-columns: 1fr;
    }
}