:root {
    --primary-color: #1d93ab;
    --primary-hover: #177a8f;
    --text-color: #303030;
    --text-light: #666666;
    --bg-color: #ffffff;
    --bg-secondary: #e7f8ff;
    --border-color: #dedede;
    --max-width: 1200px;
    --font-sans: "Noto Sans", "SF Pro SC", "SF Pro Text", "SF Pro Icons", "PingFang SC", "Helvetica Neue", "Helvetica", "Arial", sans-serif;
    --pricing-tag-content: "Most Popular";
}

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

body {
    font-family: var(--font-sans);
    color: var(--text-color);
    line-height: 1.6;
    background-color: var(--bg-color);
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
}

/* Utilities */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
}

.text-center { text-align: center; }
.mt-1 { margin-top: 1rem; }
.mt-2 { margin-top: 2rem; }
.mb-1 { margin-bottom: 1rem; }
.mb-2 { margin-bottom: 2rem; }

/* Components */
.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: 8px;
    font-weight: 600;
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
}

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

.btn-primary:hover {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
}

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

.btn-outline:hover {
    border-color: var(--text-color);
}

/* Header */
header {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid var(--border-color);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
}

.nav-left {
    display: flex;
    align-items: center;
    gap: 40px;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: 8px;
    text-decoration: none;
}

.nav-links {
    display: none;
}

@media (min-width: 768px) {
    .nav-links {
        display: flex;
        gap: 24px;
    }
}

.nav-links a {
    font-weight: 500;
    color: var(--text-color);
    transition: color 0.2s;
}

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

.nav-right {
    display: flex;
    align-items: center;
    gap: 16px;
}

.lang-btn {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 8px 16px;
    border-radius: 20px;
    background-color: var(--bg-secondary);
    color: var(--text-color);
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.2s;
    border: 1px solid transparent;
}

.lang-btn:hover {
    background-color: #e5e7eb;
}

/* Hero Section */
.hero {
    padding: 160px 0 100px;
    text-align: center;
    background: radial-gradient(circle at 50% 50%, rgba(29, 147, 171, 0.08) 0%, rgba(255, 255, 255, 0) 60%);
}

.hero h1 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

.hero p {
    font-size: 1.25rem;
    color: var(--text-light);
    max-width: 700px;
    margin: 0 auto 2.5rem;
}

.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-bottom: 4rem;
}

.hero-image {
    border-radius: 12px;
    box-shadow: 0 20px 40px -12px rgba(0, 0, 0, 0.15);
    border: 1px solid var(--border-color);
    overflow: hidden;
    max-width: 1000px;
    margin: 0 auto;
}

@media (min-width: 768px) {
    .hero h1 {
        font-size: 3.5rem;
    }
}

/* Features Section */
.features {
    padding: 100px 0;
    background-color: var(--bg-secondary);
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 1rem;
    text-align: center;
}

.section-desc {
    color: var(--text-light);
    text-align: center;
    max-width: 600px;
    margin: 0 auto 4rem;
}

.feature-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 40px;
}

@media (min-width: 768px) {
    .feature-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

.feature-card {
    background: white;
    padding: 30px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    transition: transform 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.05);
}

.feature-icon {
    width: 48px;
    height: 48px;
    background: rgba(29, 147, 171, 0.1);
    color: var(--primary-color);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
    font-size: 1.5rem;
}

/* Models Section */
.models {
    padding: 80px 0;
    text-align: center;
    border-bottom: 1px solid var(--border-color);
    background-color: #fafafa;
}

.model-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    max-width: 1000px;
    margin: 40px auto 0;
}

@media (min-width: 768px) {
    .model-grid {
        grid-template-columns: repeat(4, 1fr);
    }
}

.model-card {
    background: white;
    padding: 24px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
    transition: all 0.3s ease;
}

.model-card:hover {
    border-color: var(--primary-color);
    box-shadow: 0 4px 20px rgba(0,0,0,0.05);
    transform: translateY(-2px);
}

.google-icon {
    background: linear-gradient(90deg, #4285F4 0%, #4285F4 25%, #EA4335 25%, #EA4335 50%, #FBBC05 50%, #FBBC05 75%, #34A853 75%, #34A853 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
    display: inline-block;
}

.btn i {
    margin-right: 8px;
}

.login-btn-enhanced {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 20px;
    font-size: 0.95rem;
    box-shadow: 0 4px 6px -1px rgba(29, 147, 171, 0.3), 0 2px 4px -1px rgba(29, 147, 171, 0.1);
}

.login-btn-enhanced i {
    margin-right: 0;
}

.login-btn-enhanced:hover {
    box-shadow: 0 10px 15px -3px rgba(29, 147, 171, 0.3), 0 4px 6px -2px rgba(29, 147, 171, 0.1);
    transform: translateY(-2px);
}

.model-provider {
    font-size: 0.75rem;
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 600;
}

.model-name {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-color);
}

.feature-card h3 {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
}

.feature-card p {
    color: var(--text-light);
}

/* Pricing Section */
.pricing {
    padding: 100px 0;
}

.pricing-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 30px;
    max-width: 900px;
    margin: 0 auto;
}

@media (min-width: 768px) {
    .pricing-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

.pricing-card {
    padding: 40px;
    border-radius: 16px;
    border: 1px solid var(--border-color);
    text-align: center;
    display: flex;
    flex-direction: column;
    height: 100%;
}

.pricing-card .btn {
    margin-top: auto;
    width: 100%;
}

.pricing-card.highlight {
    border-color: var(--primary-color);
    background: linear-gradient(to bottom, rgba(29, 147, 171, 0.05), white);
    position: relative;
}

.pricing-card.highlight::before {
    content: var(--pricing-tag-content);
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--primary-color);
    color: white;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 600;
}

.price {
    font-size: 3rem;
    font-weight: 800;
    margin: 1.5rem 0;
    color: var(--text-color);
}

.price span {
    font-size: 1rem;
    color: var(--text-light);
    font-weight: 400;
}

.features-list {
    margin: 2rem 0;
    text-align: left;
    flex-grow: 1; /* Pushes the button to the bottom */
}

.features-list li {
    margin-bottom: 0.75rem;
    color: var(--text-light);
    display: flex;
    align-items: center;
    gap: 10px;
}

.features-list li::before {
    content: "✓";
    color: var(--primary-color);
    font-weight: bold;
}

/* CTA Section */
.cta {
    padding: 80px 0;
    background: var(--primary-color);
    color: white;
    text-align: center;
}

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

.cta p {
    font-size: 1.25rem;
    opacity: 0.9;
    margin-bottom: 2rem;
}

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

.cta .btn-primary:hover {
    background: #f9fafb;
}

/* Footer */
footer {
    padding: 60px 0;
    border-top: 1px solid var(--border-color);
    background: var(--bg-secondary);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 40px;
}

.footer-col h4 {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
}

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

.footer-col a {
    color: var(--text-light);
}

.footer-col a:hover {
    color: var(--primary-color);
}

.copyright {
    text-align: center;
    margin-top: 60px;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
    color: var(--text-light);
    font-size: 0.875rem;
}