/* 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: #fef5f0;
}

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

/* Header Styles */
.header {
    background: linear-gradient(135deg, #b83c3c 0%, #e05252 100%);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

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

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

.logo img {
    width: 50px;
    height: 50px;
}

.logo h1 {
    color: white;
    font-size: 1.8rem;
    font-weight: 700;
}

.nav {
    display: flex;
    gap: 2rem;
}

.nav a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: opacity 0.3s ease;
    padding: 0.5rem 1rem;
    border-radius: 5px;
}

.nav a:hover,
.nav a.active {
    background-color: rgba(255, 255, 255, 0.2);
}

/* Mobile Menu Toggle */
.menu-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
    z-index: 1001;
}

.menu-toggle span {
    width: 25px;
    height: 3px;
    background-color: white;
    margin: 3px 0;
    transition: 0.3s;
    border-radius: 3px;
}

.menu-toggle.active span:nth-child(1) {
    transform: rotate(-45deg) translate(-5px, 6px);
}

.menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.menu-toggle.active span:nth-child(3) {
    transform: rotate(45deg) translate(-5px, -6px);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #b83c3c 0%, #e05252 100%);
    padding: 4rem 0;
    text-align: center;
    color: white;
}

.hero-title {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero-subtitle {
    font-size: 1.3rem;
    opacity: 0.95;
}

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

.details-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.detail-card {
    background: linear-gradient(135deg, #fef5f0 0%, #fff 100%);
    padding: 2.5rem;
    border-radius: 20px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    text-align: center;
}

.detail-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
}

.detail-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
}

.detail-card h3 {
    font-size: 1.5rem;
    color: #b83c3c;
    margin-bottom: 1rem;
}

.detail-highlight {
    font-size: 1.8rem;
    font-weight: 700;
    color: #ffd700;
    background: linear-gradient(135deg, #b83c3c 0%, #e05252 100%);
    padding: 0.8rem;
    border-radius: 10px;
    margin-bottom: 1rem;
}

.detail-card p {
    font-size: 1rem;
    color: #666;
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.detail-list {
    list-style: none;
    text-align: left;
}

.detail-list li {
    padding: 0.5rem 0;
    padding-left: 1.5rem;
    position: relative;
    font-size: 0.95rem;
    color: #555;
}

.detail-list li:before {
    content: "•";
    position: absolute;
    left: 0;
    color: #b83c3c;
    font-size: 1.5rem;
    line-height: 1;
}

/* Example Section */
.example-section {
    padding: 4rem 0;
    background: linear-gradient(135deg, #fef5f0 0%, #ffe4d6 100%);
}

.section-title {
    font-size: 2.5rem;
    color: #b83c3c;
    text-align: center;
    margin-bottom: 1rem;
    font-weight: 700;
}

.section-subtitle {
    font-size: 1.2rem;
    color: #666;
    text-align: center;
    margin-bottom: 3rem;
}

.example-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-bottom: 3rem;
}

.example-params h3,
.example-calc h3 {
    font-size: 1.8rem;
    color: #b83c3c;
    margin-bottom: 1.5rem;
}

.param-box {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
}

.param-item {
    display: flex;
    justify-content: space-between;
    padding: 1rem 0;
    border-bottom: 1px solid #eee;
}

.param-item:last-child {
    border-bottom: none;
}

.param-label {
    font-weight: 600;
    color: #555;
}

.param-value {
    font-weight: 700;
    color: #b83c3c;
}

.calc-steps {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.calc-step {
    background: white;
    padding: 1.5rem;
    border-radius: 15px;
    box-shadow: 0 3px 15px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s ease;
}

.calc-step:hover {
    transform: translateX(5px);
}

.calc-step.highlight {
    background: linear-gradient(135deg, #fff3e0 0%, #ffe4cc 100%);
    border-left: 4px solid #ff9800;
}

.calc-label {
    font-weight: 600;
    color: #555;
    margin-bottom: 0.5rem;
}

.calc-formula {
    font-size: 1.2rem;
    font-weight: 700;
    color: #b83c3c;
    font-family: 'Courier New', monospace;
}

.example-summary {
    background: white;
    padding: 2.5rem;
    border-radius: 20px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
}

.example-summary h3 {
    font-size: 2rem;
    color: #b83c3c;
    text-align: center;
    margin-bottom: 2rem;
}

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

.summary-item {
    text-align: center;
    padding: 1.5rem;
    background: #fef5f0;
    border-radius: 15px;
}

.summary-label {
    display: block;
    font-size: 1rem;
    color: #666;
    margin-bottom: 0.5rem;
}

.summary-value {
    display: block;
    font-size: 2rem;
    font-weight: 700;
    color: #333;
}

.summary-value.green {
    color: #4caf50;
}

.summary-value.red {
    color: #b83c3c;
}

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

.calculator-box {
    background: linear-gradient(135deg, #fef5f0 0%, #fff 100%);
    padding: 3rem;
    border-radius: 20px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
}

.input-group {
    margin-bottom: 2rem;
}

.input-group label {
    display: block;
    font-size: 1.1rem;
    font-weight: 600;
    color: #555;
    margin-bottom: 0.5rem;
}

.input-group input {
    width: 100%;
    padding: 1rem;
    font-size: 1.2rem;
    border: 2px solid #ddd;
    border-radius: 10px;
    transition: border-color 0.3s ease;
}

.input-group input:focus {
    outline: none;
    border-color: #b83c3c;
}

.input-range {
    display: flex;
    justify-content: space-between;
    margin-top: 0.5rem;
    font-size: 0.9rem;
    color: #999;
}

.calc-button {
    width: 100%;
    padding: 1.2rem;
    background: linear-gradient(135deg, #b83c3c 0%, #e05252 100%);
    color: white;
    font-size: 1.3rem;
    font-weight: 700;
    border: none;
    border-radius: 50px;
    cursor: pointer;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    box-shadow: 0 5px 20px rgba(184, 60, 60, 0.3);
}

.calc-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(184, 60, 60, 0.4);
}

.calculator-result h3 {
    font-size: 1.8rem;
    color: #b83c3c;
    margin-bottom: 1.5rem;
}

.result-content {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 3px 15px rgba(0, 0, 0, 0.08);
}

.result-item {
    display: flex;
    justify-content: space-between;
    padding: 1rem 0;
    border-bottom: 1px solid #eee;
}

.result-item:last-child {
    border-bottom: none;
}

.result-item.highlight {
    background: linear-gradient(135deg, #fff3e0 0%, #ffe4cc 100%);
    padding: 1rem;
    border-radius: 10px;
    margin: 0.5rem 0;
    border-bottom: none;
}

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

.result-value {
    font-weight: 700;
    color: #b83c3c;
}

.result-value.total {
    font-size: 1.3rem;
    color: #e05252;
}

/* CTA Section */
.cta-section {
    background: linear-gradient(135deg, #b83c3c 0%, #e05252 100%);
    padding: 4rem 0;
    text-align: center;
}

.cta-content h2 {
    font-size: 2.5rem;
    color: white;
    margin-bottom: 1rem;
}

.cta-content p {
    font-size: 1.2rem;
    color: white;
    margin-bottom: 2rem;
}

.cta-button {
    display: inline-block;
    background: linear-gradient(135deg, #ffd700 0%, #ffed4e 100%);
    color: #333;
    padding: 1rem 3rem;
    border-radius: 50px;
    text-decoration: none;
    font-size: 1.2rem;
    font-weight: 700;
    box-shadow: 0 5px 20px rgba(255, 215, 0, 0.4);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.cta-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(255, 215, 0, 0.6);
}

/* Footer */
.footer {
    background: #2c2c2c;
    color: white;
    padding: 3rem 0 1rem;
}

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

.footer-section h3,
.footer-section h4 {
    color: #ffd700;
    margin-bottom: 1rem;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 1rem;
}

.footer-logo img {
    width: 40px;
    height: 40px;
}

.footer-section p {
    color: #ccc;
    line-height: 1.8;
}

.footer-section p a {
    color: #ccc;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section p a:hover {
    color: #ffd700;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section ul li a {
    color: #ccc;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section ul li a:hover {
    color: #ffd700;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #444;
    color: #999;
}

/* Responsive Design */
@media (max-width: 768px) {
    .header .container {
        flex-wrap: wrap;
    }

    .menu-toggle {
        display: flex;
        order: 2;
    }

    .logo {
        order: 1;
    }

    .nav {
        order: 3;
        width: 100%;
        flex-direction: column;
        gap: 0;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.3s ease;
        margin-top: 1rem;
    }

    .nav.active {
        max-height: 500px;
    }

    .nav a {
        padding: 1rem;
        border-radius: 0;
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    }

    .hero-title {
        font-size: 2rem;
    }

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

    .example-content {
        grid-template-columns: 1fr;
    }

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

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

    .footer-content {
        grid-template-columns: 1fr;
    }
}