/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

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

/* Header Styles */
header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 1rem 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

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

.logo {
    font-size: 1.8rem;
    font-weight: bold;
}

/* Navigation */
nav ul {
    display: flex;
    list-style: none;
    gap: 2rem;
}

nav a {
    color: white;
    text-decoration: none;
    transition: opacity 0.3s;
}

nav a:hover {
    opacity: 0.8;
}

/* Hero Section */
.hero {
    text-align: center;
    padding: 4rem 0;
    background: white;
    margin: 2rem 0;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: #333;
}

.hero p {
    font-size: 1.2rem;
    color: #666;
}

/* Categories Grid */
.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 3rem 0;
}

.category-card {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}

.category-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.15);
}

.category-card h2 {
    color: #667eea;
    margin-bottom: 1.5rem;
    border-bottom: 2px solid #667eea;
    padding-bottom: 0.5rem;
}

.tools-list {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.tools-list a {
    color: #555;
    text-decoration: none;
    padding: 0.5rem;
    border-radius: 5px;
    transition: all 0.3s;
}

.tools-list a:hover {
    background: #f0f4ff;
    color: #667eea;
    padding-left: 1rem;
}

/* Calculator Form Styles */
.calculator-form {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    margin: 2rem 0;
}

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

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: #555;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 0.8rem;
    border: 2px solid #e1e5e9;
    border-radius: 5px;
    font-size: 1rem;
    transition: border-color 0.3s;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: #667eea;
}

.btn {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 1rem 2rem;
    border-radius: 5px;
    font-size: 1rem;
    cursor: pointer;
    transition: transform 0.3s, box-shadow 0.3s;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

/* Results Section */
.results {
    background: #f8f9ff;
    padding: 2rem;
    border-radius: 10px;
    margin-top: 2rem;
    border-left: 4px solid #667eea;
}

.result-item {
    display: flex;
    justify-content: between;
    margin-bottom: 1rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid #e1e5e9;
}

.result-label {
    font-weight: 600;
    color: #555;
    flex: 1;
}

.result-value {
    font-weight: bold;
    color: #667eea;
    flex: 1;
    text-align: right;
}

/* Footer */
footer {
    background: #333;
    color: white;
    text-align: center;
    padding: 2rem 0;
    margin-top: 4rem;
}