/* Global Styles */
:root {
    --bg-primary: #f8f9fa;
    --bg-secondary: #ffffff;
    --text-primary: #2c3e50;
    --text-secondary: #666666;
    --accent-primary: #4CAF50;
    --accent-secondary: #2196F3;
    --border-color: #e0e0e0;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --hover-shadow: rgba(0, 0, 0, 0.15);
    --gradient-start: #4CAF50;
    --gradient-end: #2196F3;
}

[data-theme="dark"] {
    --bg-primary: #1a1a1a;
    --bg-secondary: #2d2d2d;
    --text-primary: #ffffff;
    --text-secondary: #b3b3b3;
    --accent-primary: #66bb6a;
    --accent-secondary: #42a5f5;
    --border-color: #404040;
    --shadow-color: rgba(0, 0, 0, 0.3);
    --hover-shadow: rgba(0, 0, 0, 0.4);
    --gradient-start: #66bb6a;
    --gradient-end: #42a5f5;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 20px;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    text-align: center;
}

h1 {
    color: var(--text-primary);
    margin-bottom: 20px;
    font-size: 2.8em;
    font-weight: 700;
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

p {
    color: var(--text-secondary);
    font-size: 1.2em;
    margin-bottom: 40px;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

/* Converter Container */
.converter-container {
    display: flex;
    justify-content: center;
    gap: 40px;
    margin-top: 60px;
    flex-wrap: wrap;
}

/* Converter Cards */
.converter-card {
    background-color: var(--bg-secondary);
    border-radius: 20px;
    padding: 40px;
    width: 320px;
    box-shadow: 0 8px 25px var(--shadow-color);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
    border: 1px solid var(--border-color);
}

.converter-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--gradient-start), var(--gradient-end));
}

.converter-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 35px var(--hover-shadow);
}

.converter-card h2 {
    color: var(--text-primary);
    margin-bottom: 15px;
    font-size: 1.8em;
}

.converter-card p {
    color: var(--text-secondary);
    margin-bottom: 30px;
    font-size: 1.1em;
}

.converter-card a {
    display: inline-block;
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    color: white;
    padding: 14px 32px;
    text-decoration: none;
    border-radius: 12px;
    font-weight: 600;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-size: 1.1em;
    border: none;
}

.converter-card a:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 15px var(--shadow-color);
    filter: brightness(1.1);
}

/* Theme Toggle Button */
.theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    background-color: var(--bg-secondary);
    border: 2px solid var(--border-color);
    color: var(--text-primary);
    padding: 10px;
    border-radius: 50%;
    cursor: pointer;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
    z-index: 1000;
}

.theme-toggle:hover {
    transform: rotate(30deg);
    border-color: var(--accent-primary);
}

/* Responsive Design */
@media (max-width: 768px) {
    body {
        padding: 20px;
    }
    
    h1 {
        font-size: 2.2em;
    }
    
    .converter-container {
        gap: 20px;
    }
    
    .converter-card {
        width: 100%;
        max-width: 400px;
        padding: 30px;
    }
    
    .theme-toggle {
        top: 10px;
        right: 10px;
    }
}