:root {
    --primary-blue: #1e3a8a;
    --primary-purple: #7c3aed;
    --primary-cyan: #06b6d4;
    --gradient-header: linear-gradient(135deg, #1e3a8a, #7c3aed, #06b6d4);
    --bg-light: #ffffff;
    --text-dark: #1f2937;
    --text-muted: #4b5563;
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --max-width: 1200px;
}

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

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-light);
    overflow-x: hidden;
}

body.menu-open {
    overflow: hidden;
}

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

ul {
    list-style: none;
}

/* Header & Navigation */
.header-gradient {
    background: var(--gradient-header);
    height: 5px;
    width: 100%;
}

header {
    background: white;
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 1rem 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    background: var(--gradient-header);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.025em;
}

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

.nav-links a {
    font-weight: 500;
    color: var(--text-muted);
}

.nav-links a:hover {
    color: var(--primary-purple);
}

.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 30px;
    height: 21px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 2001;
}

.menu-toggle span {
    width: 100%;
    height: 3px;
    background-color: var(--primary-blue);
    border-radius: 10px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.menu-toggle.active span:nth-child(1) {
    transform: translateY(9px) rotate(45deg);
}

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

.menu-toggle.active span:nth-child(3) {
    transform: translateY(-9px) rotate(-45deg);
}

/* Footer */
footer {
    background: #f9fafb;
    border-top: 5px solid;
    border-image: var(--gradient-header) 1;
    padding: 4rem 1.5rem 2rem;
    margin-top: 4rem;
}

.footer-container {
    max-width: var(--max-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 3rem;
}

.footer-col h3 {
    margin-bottom: 1.5rem;
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary-blue);
}

.footer-links li {
    margin-bottom: 0.75rem;
}

/* Tool Side Selection & Related */
.related-tools-section {
    margin-top: 6rem;
    padding-top: 4rem;
    border-top: 1px solid var(--border-color);
}

.footer-bottom {
    max-width: var(--max-width);
    margin: 3rem auto 0;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
    text-align: center;
    color: var(--text-muted);
    font-size: 0.875rem;
}

/* Hero Section */
.hero {
    background: var(--gradient-header);
    color: white;
    padding: 6rem 1.5rem;
    text-align: center;
}

.hero h1 {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    line-height: 1.1;
}

.hero p {
    font-size: 1.25rem;
    max-width: 800px;
    margin: 0 auto 2.5rem;
    opacity: 0.9;
}

.btn {
    display: inline-block;
    padding: 1rem 2rem;
    border-radius: 0.5rem;
    font-weight: 600;
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

/* Testimonial Slider (Infinite Scroll) */
.testimonial-section {
    padding: 6rem 0;
    overflow: hidden;
    background: #ffffff;
    position: relative;
}

.testimonial-section::before,
.testimonial-section::after {
    content: "";
    position: absolute;
    top: 0;
    width: 250px;
    height: 100%;
    z-index: 2;
    pointer-events: none;
}

.testimonial-section::before {
    left: 0;
    background: linear-gradient(to right, #ffffff, rgba(255, 255, 255, 0));
}

.testimonial-section::after {
    right: 0;
    background: linear-gradient(to left, #ffffff, rgba(255, 255, 255, 0));
}

.testimonial-row {
    display: flex;
    width: max-content;
    animation: marquee 30s linear infinite;
}

.testimonial-row:hover {
    animation-play-state: paused;
}

.testimonial-card {
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 1.5rem;
    padding: 2rem;
    margin: 0 1.5rem;
    width: 350px;
    flex-shrink: 0;
    box-shadow: 0 10px 30px rgba(0,0,0,0.03);
    transition: transform 0.3s ease;
}

.testimonial-card:hover {
    transform: translateY(-5px);
    border-color: var(--primary-purple);
}

.testimonial-header {
    display: flex;
    align-items: center;
    gap: 1.25rem;
    margin-bottom: 1.5rem;
}

.testimonial-img {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    object-fit: cover;
    border: 3px solid #f1f5f9;
}

.testimonial-name {
    font-weight: 800;
    font-size: 1.1rem;
    color: var(--text-dark);
}

.stars {
    color: #f59e0b; /* Warmer amber star color */
    font-size: 1rem;
    margin-top: 0.3rem;
    letter-spacing: 2px;
}

@keyframes marquee {
    0% { transform: translateX(0); }
    100% { transform: translateX(-50%); }
}

/* Tool Grid */
.section-container {
    max-width: var(--max-width);
    margin: 4rem auto;
    padding: 0 1.5rem;
}

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

.card {
    background: white;
    border-radius: 1rem;
    padding: 2rem;
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-cyan);
}

.card-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: var(--primary-purple);
}

.card-title {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    color: var(--primary-blue);
}

.card-desc {
    color: var(--text-muted);
    font-size: 0.9375rem;
    margin-bottom: 1.5rem;
    flex-grow: 1;
}

.btn-sm {
    padding: 0.75rem 1.5rem;
    font-size: 0.875rem;
    background: var(--gradient-header);
    color: white;
    text-align: center;
}

/* Calculator Form */
.calculator-container {
    max-width: 700px;
    margin: 4rem auto;
    padding: 3rem;
    background: white;
    border-radius: 1.5rem;
    box-shadow: var(--shadow-lg);
}

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

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text-dark);
}

.form-control {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    font-size: 1rem;
}

.calculate-btn {
    width: 100%;
    padding: 1rem;
    background: var(--gradient-header);
    color: white;
    border: none;
    border-radius: 0.5rem;
    font-weight: 700;
    font-size: 1.125rem;
    cursor: pointer;
    margin-top: 1rem;
}

.result-display {
    margin-top: 2rem;
    padding: 2rem;
    background: #f0f9ff;
    border-radius: 1rem;
    text-align: center;
    display: none;
}

.result-value {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--primary-blue);
}

/* Breadcrumbs */
.breadcrumb {
    max-width: var(--max-width);
    margin: 1.5rem auto 0;
    padding: 0 1.5rem;
    font-size: 0.875rem;
    color: var(--text-muted);
}

.breadcrumb a {
    color: var(--primary-blue);
}

.breadcrumb span {
    margin: 0 0.5rem;
}

/* Tool Top Dropdown */
.tool-nav-top {
    background: #f8fafc;
    border-bottom: 1px solid var(--border-color);
    padding: 0.5rem 0;
}

.tool-nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    justify-content: flex-end;
}

.tool-select {
    padding: 0.4rem 1rem;
    border-radius: 0.25rem;
    border: 1px solid var(--border-color);
    font-size: 0.9rem;
    color: var(--text-dark);
}
/* Responsive Design */
@media (max-width: 1024px) {
    .hero h1 {
        font-size: 3rem;
    }
}

@media (max-width: 768px) {
    .menu-toggle {
        display: flex;
    }

    .nav-links {
        display: flex;
        position: fixed;
        top: 0;
        right: -100%;
        width: 100%;
        height: 100vh;
        background: white;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        padding: 4rem 2rem;
        gap: 2rem;
        transition: right 0.4s cubic-bezier(0.4, 0, 0.2, 1);
        box-shadow: -10px 0 30px rgba(0,0,0,0.1);
        z-index: 2000;
        margin: 0;
    }

    .nav-links.active {
        right: 0;
    }

    .nav-links li {
        width: 100%;
        text-align: center;
    }

    .nav-links a {
        display: block;
        padding: 1rem;
        font-size: 1.25rem;
        width: 100%;
    }
    
    .hero {
        padding: 4rem 1.5rem;
    }
    
    .hero h1 {
        font-size: 2.25rem;
    }
    
    .hero p {
        font-size: 1.1rem;
    }

    .section-container {
        margin: 2rem auto;
    }

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

    .calculator-container {
        padding: 1.5rem;
        margin: 2rem auto;
    }

    .footer-container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .social-links {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .hero h1 {
        font-size: 1.75rem;
    }
    
    .card {
        padding: 1.5rem;
    }

    .result-value {
        font-size: 2rem;
    }
}