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

:root {
    --primary: #0078d4;
    --secondary: #40e0d0;
    --dark: #1a1a1a;
    --light: #f8f9fa;
    --text: #333333;
    --text-light: #666666;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.15);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.5;
    color: var(--text);
    overflow-x: hidden;
    font-size: 18px;
}

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

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow);
    z-index: 1000;
    transition: all 0.3s ease;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 20px;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 20px;
    font-weight: 600;
    color: var(--dark);
}

.nav-brand .logo {
    width: 32px;
    height: 32px;
}

.nav-links {
    display: flex;
    gap: 30px;
    align-items: center;
}

.nav-links a {
    text-decoration: none;
    color: var(--text);
    font-weight: 500;
    font-size: 17px;
    transition: color 0.3s ease;
}

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

.btn-nav {
    padding: 8px 20px;
    background: var(--primary);
    color: white !important;
    border-radius: 25px;
}

.btn-nav:hover {
    background: #106ebe;
    transform: translateY(-2px);
}

/* Hero Section */
.hero {
    padding: 60px 0 30px;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    min-height: auto;
    display: flex;
    align-items: center;
}

.hero-content {
    text-align: center;
    margin-bottom: 30px;
}

.hero-title {
    font-size: 56px;
    font-weight: 700;
    color: var(--dark);
    margin-bottom: 15px;
    line-height: 1.1;
}

.gradient-text {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    display: block;
}

.hero-subtitle {
    font-size: 22px;
    color: var(--text);
    max-width: 700px;
    margin: 0 auto 25px;
    line-height: 1.4;
}

.hero-actions {
    display: flex;
    gap: 20px;
    justify-content: center;
}

.btn {
    padding: 14px 35px;
    border-radius: 30px;
    text-decoration: none;
    font-weight: 600;
    font-size: 18px;
    transition: all 0.3s ease;
    display: inline-block;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: var(--primary);
    color: white;
    box-shadow: 0 4px 15px rgba(0, 120, 212, 0.3);
}

.btn-primary:hover {
    background: #106ebe;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 120, 212, 0.4);
}

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

.btn-secondary:hover {
    background: var(--primary);
    color: white;
    transform: translateY(-2px);
}

.btn-large {
    padding: 18px 45px;
    font-size: 20px;
}

/* Hero Visual */
.hero-visual {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px 0;
}

/* Visual Demo Section */
.visual-demo {
    background: white;
    padding: 40px 0;
}

/* Features Section */
.features {
    padding: 25px 0;
    background: white;
}

.section-title {
    font-size: 38px;
    text-align: center;
    color: var(--dark);
    margin-bottom: 8px;
}

.section-subtitle {
    text-align: center;
    color: var(--text-light);
    font-size: 18px;
    margin-bottom: 20px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 20px;
}

.feature-card {
    padding: 18px;
    background: var(--light);
    border-radius: 10px;
    text-align: center;
    transition: all 0.3s ease;
}

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

.feature-icon {
    width: 50px;
    height: 50px;
    margin: 0 auto 15px;
}

.feature-card h3 {
    font-size: 20px;
    color: var(--dark);
    margin-bottom: 6px;
}

.feature-card p {
    color: var(--text-light);
    line-height: 1.3;
    font-size: 16px;
}

/* How It Works */
.how-it-works {
    padding: 30px 0;
    background: linear-gradient(to bottom, var(--light), white);
}

.steps {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 900px;
    margin: 0 auto;
}

.step {
    flex: 1;
    text-align: center;
    padding: 15px;
}

.step-number {
    width: 60px;
    height: 60px;
    background: var(--primary);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    font-weight: bold;
    margin: 0 auto 20px;
}

.step h3 {
    font-size: 20px;
    color: var(--dark);
    margin-bottom: 10px;
}

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

.step-arrow {
    font-size: 30px;
    color: var(--primary);
}

/* Installation Section */
.installation {
    padding: 35px 0;
    background: white;
}

.install-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 40px;
    margin-top: 40px;
}

.install-method {
    background: var(--light);
    padding: 20px;
    border-radius: 10px;
}

.install-method h3 {
    color: var(--primary);
    margin-bottom: 20px;
    font-size: 24px;
}

.install-method ol {
    list-style: none;
    counter-reset: step-counter;
}

.install-method li {
    counter-increment: step-counter;
    padding: 10px 0;
    position: relative;
    padding-left: 35px;
    font-size: 18px;
}

.install-method li::before {
    content: counter(step-counter);
    position: absolute;
    left: 0;
    top: 8px;
    background: var(--primary);
    color: white;
    width: 25px;
    height: 25px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    font-weight: bold;
}

/* Download Section */
.download {
    padding: 40px 0;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
}

.download-box {
    text-align: center;
    color: white;
    max-width: 600px;
    margin: 0 auto;
}

.download-box h2 {
    font-size: 48px;
    margin-bottom: 20px;
}

.download-box p {
    font-size: 22px;
    margin-bottom: 30px;
    opacity: 0.9;
}

.download-actions {
    display: flex;
    gap: 20px;
    justify-content: center;
    margin-bottom: 20px;
}

.download-note {
    font-size: 14px;
    opacity: 0.8;
}

/* Footer */
.footer {
    background: var(--dark);
    color: white;
    padding: 25px 0 15px;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 18px;
}

.footer-brand .logo {
    width: 30px;
    height: 30px;
}

.footer-links {
    display: flex;
    gap: 30px;
}

.footer-links a {
    color: white;
    text-decoration: none;
    opacity: 0.8;
    transition: opacity 0.3s ease;
}

.footer-links a:hover {
    opacity: 1;
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    opacity: 0.6;
    font-size: 14px;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .hero-title {
        font-size: 36px;
    }

    .hero-actions {
        flex-direction: column;
        align-items: center;
    }

    .spreadsheet-demo {
        flex-direction: column;
    }

    .steps {
        flex-direction: column;
    }

    .step-arrow {
        transform: rotate(90deg);
    }

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

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

    .download-actions {
        flex-direction: column;
        align-items: center;
    }

    .footer-content {
        flex-direction: column;
        gap: 20px;
    }
}