:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --secondary-color: #64748b;
    --secondary-hover: #475569;
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --text-color: #1e293b;
    --border-color: #e2e8f0;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
}

header {
    background-color: var(--card-bg);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
}

nav {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 1.5rem;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.2s;
}

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

main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

section {
    margin-bottom: 4rem;
}

.hero {
    text-align: center;
    padding: 4rem 2rem;
    background: linear-gradient(135deg, #eff6ff 0%, #ffffff 100%);
    border-radius: 12px;
}

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

.hero p {
    font-size: 1.25rem;
    color: var(--secondary-color);
    margin-bottom: 2rem;
}

.btn-primary,
.btn-secondary {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
}

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

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

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

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

button:active {
    transform: scale(0.98);
}

.hidden {
    display: none;
}

#cta-message {
    margin-top: 1rem;
    color: var(--primary-color);
    font-weight: 600;
}

.features h2,
.test-area h2,
.contact h2 {
    text-align: center;
    margin-bottom: 2rem;
    font-size: 2rem;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
}

.feature-card {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.feature-card h3 {
    color: var(--primary-color);
    margin-bottom: 0.75rem;
}

.test-area {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.test-box {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.test-box label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.test-box input,
.test-box textarea {
    width: 100%;
    padding: 0.75rem;
    margin-bottom: 1rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
}

#counter-value {
    font-size: 3rem;
    font-weight: 700;
    color: var(--primary-color);
    text-align: center;
    margin: 1rem 0;
}

.counter-controls {
    display: flex;
    justify-content: center;
    gap: 0.75rem;
}

.contact form {
    max-width: 600px;
    margin: 0 auto;
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.contact label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.contact input,
.contact textarea {
    width: 100%;
    padding: 0.75rem;
    margin-bottom: 1rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    font-family: inherit;
}

#form-status {
    margin-top: 1rem;
    font-weight: 600;
}

footer {
    text-align: center;
    padding: 2rem;
    background-color: var(--card-bg);
    border-top: 1px solid var(--border-color);
    color: var(--secondary-color);
}

@media (max-width: 768px) {
    .hero h1 {
        font-size: 2rem;
    }

    .nav-links {
        gap: 1rem;
        font-size: 0.9rem;
    }

    main {
        padding: 1rem;
    }
}