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

:root {
    --primary-color: #0d7377;
    --primary-light: #14a0a5;
    --primary-dark: #065254;
    --accent-color: #f97316;
    --accent-light: #fb923c;
    --accent-dark: #ea580c;

    --bg-color: #f8fafc;
    --surface-color: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;

    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;

    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.5rem;
    --font-size-2xl: 2rem;
    --font-size-3xl: 2.5rem;

    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;

    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);

    --transition-fast: 150ms ease;
    --transition-base: 300ms ease;
    --transition-slow: 500ms ease;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-color);
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

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

a {
    text-decoration: none;
    color: inherit;
    transition: color var(--transition-fast);
}

button {
    cursor: pointer;
    border: none;
    background: none;
    font-family: inherit;
    transition: all var(--transition-fast);
}

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

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-sm) 0;
}

.logo {
    display: flex;
    align-items: center;
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--primary-color);
}

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

.nav-list {
    display: flex;
    gap: var(--spacing-lg);
    list-style: none;
}

.nav-list a {
    font-weight: 500;
    color: var(--text-secondary);
    position: relative;
}

.nav-list a:hover,
.nav-list a.active {
    color: var(--primary-color);
}

.nav-list a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--accent-color);
    transition: width var(--transition-base);
}

.nav-list a:hover::after,
.nav-list a.active::after {
    width: 100%;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    padding: 8px;
}

.mobile-menu-toggle span {
    width: 24px;
    height: 2px;
    background-color: var(--text-primary);
    transition: var(--transition-base);
}

.btn-primary {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-lg);
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    color: white;
    border-radius: var(--radius-md);
    font-weight: 600;
    box-shadow: var(--shadow-md);
    transition: all var(--transition-base);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    background: linear-gradient(135deg, var(--primary-dark), var(--primary-color));
}

.btn-secondary {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-lg);
    background-color: var(--accent-color);
    color: white;
    border-radius: var(--radius-md);
    font-weight: 600;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
}

.btn-secondary:hover {
    background-color: var(--accent-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.footer {
    background-color: var(--text-primary);
    color: white;
    margin-top: var(--spacing-xl);
    padding: var(--spacing-xl) 0 var(--spacing-md);
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-lg);
}

.footer-brand {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.footer-brand img {
    width: 50px;
    height: 50px;
    filter: brightness(.8);
}

.footer-brand h3 {
    font-size: var(--font-size-xl);
    color: var(--primary-light);
}

.footer-brand p {
    color: #94a3b8;
    max-width: 500px;
}

.footer-links h4 {
    color: var(--accent-light);
    margin-bottom: var(--spacing-sm);
    font-size: var(--font-size-lg);
}

.footer-links ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.footer-links a {
    color: #94a3b8;
    transition: color var(--transition-fast);
}

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

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-md);
    border-top: 1px solid #334155;
    color: #64748b;
}

.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-light));
    color: white;
    border-radius: 50%;
    font-size: var(--font-size-xl);
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
    z-index: 999;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 25px -5px rgba(0, 0, 0, 0.2);
}

.section-title {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-lg);
    position: relative;
    padding-bottom: var(--spacing-sm);
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, var(--accent-color), var(--accent-light));
    border-radius: 2px;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: var(--spacing-lg) auto;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

@media (max-width: 768px) {
    :root {
        --font-size-2xl: 1.5rem;
        --font-size-3xl: 2rem;
    }

    .nav {
        display: none;
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .nav.mobile-active {
        display: block;
        position: absolute;
        top: 100%;
        height: 100vh;
        left: 0;
        right: 0;
        background-color: var(--surface-color);
        box-shadow: var(--shadow-md);
        padding: var(--spacing-md);
    }

    .nav.mobile-active .nav-list {
        flex-direction: column;
        gap: var(--spacing-sm);
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: var(--spacing-lg);
    }

    .back-to-top {
        width: 45px;
        height: 45px;
        bottom: 20px;
        right: 20px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-sm);
    }

    .logo {
        font-size: var(--font-size-lg);
    }

    .logo img {
        width: 32px;
        height: 32px;
    }
}