:root {
    --primary-color: #8250df;
    --primary-hover: #6e40c9;
    --banner-color: #001f3f;
    --banner-gradient: #003366;
    --secondary-color: #50e6ff;
    --success-color: #13a10e;
    --warning-color: #ffb900;
    --danger-color: #d13438;
    --text-primary: #323130;
    --text-secondary: #605e5c;
    --bg-primary: #ffffff;
    --bg-secondary: #f3f2f1;
    --border-color: #d2d0ce;
    --shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 4px 16px rgba(0, 0, 0, 0.15);
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-secondary);
}

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

/* Header */
header {
    background: linear-gradient(135deg, var(--banner-color), var(--banner-gradient));
    color: white;
    padding: 60px 20px;
    text-align: center;
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
}

header .subtitle {
    font-size: 1.2rem;
    opacity: 0.9;
}

/* Navigation */
nav {
    background-color: var(--bg-primary);
    padding: 15px 0;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

nav a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
}

nav a:hover {
    text-decoration: underline;
}

/* Main Content */
main {
    padding: 40px 20px;
}

.intro {
    background-color: var(--bg-primary);
    padding: 30px;
    border-radius: 8px;
    margin-bottom: 40px;
    box-shadow: var(--shadow);
}

.intro h2 {
    color: var(--primary-color);
    margin-bottom: 15px;
}

/* Calculator Grid */
.calculator-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: 60px;
}

.calculator-card {
    background-color: var(--bg-primary);
    padding: 30px;
    border-radius: 8px;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
}

.calculator-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.calculator-card.featured {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: 2px solid #5a67d8;
    position: relative;
    overflow: hidden;
}

.calculator-card.featured::before {
    content: "NEW";
    position: absolute;
    top: 15px;
    right: 15px;
    background: rgba(255, 255, 255, 0.3);
    padding: 4px 12px;
    border-radius: 12px;
    font-size: 0.75rem;
    font-weight: bold;
    letter-spacing: 1px;
}

.calculator-card.featured h3,
.calculator-card.featured p,
.calculator-card.featured .features li {
    color: white;
}

.calculator-card.featured .features li::before {
    color: #fbbf24;
}

.calculator-card.featured:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 30px rgba(102, 126, 234, 0.4);
}

.card-icon {
    font-size: 3rem;
    margin-bottom: 15px;
}

.calculator-card h3 {
    color: var(--primary-color);
    margin-bottom: 15px;
    font-size: 1.5rem;
}

.calculator-card p {
    color: var(--text-secondary);
    margin-bottom: 20px;
    flex-grow: 1;
}

.calculator-card .features {
    list-style: none;
    margin-bottom: 20px;
    padding-left: 0;
}

.calculator-card .features li {
    padding: 5px 0;
    color: var(--text-secondary);
}

.calculator-card .features li::before {
    content: "✓ ";
    color: var(--success-color);
    font-weight: bold;
    margin-right: 8px;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: 4px;
    text-decoration: none;
    font-weight: 600;
    text-align: center;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

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

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

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

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

/* Features Section */
.features-section {
    background-color: var(--bg-primary);
    padding: 40px;
    border-radius: 8px;
    margin-bottom: 40px;
    box-shadow: var(--shadow);
}

.features-section h2 {
    color: var(--primary-color);
    text-align: center;
    margin-bottom: 40px;
}

.feature-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.feature-item h4 {
    color: var(--primary-color);
    margin-bottom: 10px;
}

.feature-item p {
    color: var(--text-secondary);
}

/* CTA Section */
.cta-section {
    background: linear-gradient(135deg, var(--primary-color), #005a9e);
    color: white;
    padding: 50px;
    border-radius: 8px;
    text-align: center;
    box-shadow: var(--shadow);
}

.cta-section h2 {
    margin-bottom: 15px;
}

.cta-section p {
    font-size: 1.1rem;
    margin-bottom: 25px;
    opacity: 0.9;
}

/* Footer */
footer {
    background-color: var(--text-primary);
    color: white;
    padding: 30px 20px;
    text-align: center;
    margin-top: 60px;
}

footer a {
    color: var(--secondary-color);
    text-decoration: none;
}

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

/* Calculator Page Styles */
.calculator-container {
    max-width: 900px;
    margin: 40px auto;
    background-color: var(--bg-primary);
    padding: 40px;
    border-radius: 8px;
    box-shadow: var(--shadow);
}

.calculator-header {
    text-align: center;
    margin-bottom: 40px;
}

.calculator-header h1 {
    color: var(--primary-color);
    margin-bottom: 10px;
}

.calculator-header p {
    color: var(--text-secondary);
}

.form-section {
    margin-bottom: 30px;
    padding: 20px;
    background-color: var(--bg-secondary);
    border-radius: 8px;
}

.form-section h3 {
    color: var(--primary-color);
    margin-bottom: 20px;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 10px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: var(--text-primary);
    font-weight: 600;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 1rem;
    font-family: inherit;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 120, 212, 0.1);
}

.form-group small {
    display: block;
    margin-top: 5px;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.results-section {
    margin-top: 40px;
    padding: 30px;
    background: linear-gradient(135deg, #f3f2f1, #e1dfdd);
    border-radius: 8px;
    border-left: 4px solid var(--primary-color);
}

.results-section h3 {
    color: var(--primary-color);
    margin-bottom: 20px;
}

.result-card {
    background-color: white;
    padding: 20px;
    margin-bottom: 15px;
    border-radius: 4px;
    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.1);
}

.result-card h4 {
    color: var(--primary-color);
    margin-bottom: 10px;
}

.result-value {
    font-size: 2rem;
    font-weight: bold;
    color: var(--primary-color);
    margin: 10px 0;
}

.result-positive {
    color: var(--success-color);
}

.result-negative {
    color: var(--danger-color);
}

.result-warning {
    color: var(--warning-color);
}

/* Responsive */
@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }

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

    .feature-list {
        grid-template-columns: 1fr;
    }

    .calculator-container {
        padding: 20px;
    }
}