:root {
    --color-primary: #208099;
    --color-primary-dark: #1a6a7f;
    --color-accent: #e68266;
    --color-text: #1f3a42;
    --color-text-light: #5a6c6d;
    --color-bg: #f8f8f6;
    --color-white: #ffffff;
    --color-border: #e0e0e0;
    --color-success: #27ae60;
    --color-error: #e74c3c;
    --color-warning: #f39c12;
    --spacing-xs: 8px;
    --spacing-sm: 12px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-2xl: 48px;
    --border-radius: 8px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --shadow-sm: 0 1px 3px rgba(31, 58, 66, 0.12);
    --shadow-md: 0 4px 12px rgba(31, 58, 66, 0.15);
    --shadow-lg: 0 12px 32px rgba(31, 58, 66, 0.15);
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    color: var(--color-text);
    background-color: var(--color-bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Navigation */
header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background-color: var(--color-white);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-sm);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-lg) var(--spacing-xl);
    max-width: 1200px;
    margin: 0 auto;
}

.logo {
    font-size: 24px;
    font-weight: 700;
    color: var(--color-primary);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.logo svg {
    width: 28px;
    height: 28px;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: var(--spacing-2xl);
    align-items: center;
}

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

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

.nav-links a:not(.cta-button)::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--color-primary);
    transition: var(--transition);
}

.nav-links a:not(.cta-button):hover::after {
    width: 100%;
}

/* CTA Button - Navigation */
.nav-links .cta-button {
    background-color: var(--color-primary);
    color: var(--color-white);
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: var(--border-radius);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    border: 2px solid var(--color-primary);
    display: inline-block;
}

.nav-links .cta-button:hover {
    background-color: var(--color-primary-dark);
    border-color: var(--color-primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* Philosophy Introduction Section */
.philosophy-intro {
    padding: var(--spacing-2xl) var(--spacing-xl);
    background: linear-gradient(135deg, #f8f8f6 0%, #f0f0ed 100%);
    text-align: center;
}

.philosophy-container {
    max-width: 900px;
    margin: 0 auto;
}

.philosophy-intro h2 {
    font-size: clamp(24px, 5vw, 36px);
    font-weight: 700;
    margin-bottom: var(--spacing-lg);
    line-height: 1.3;
    color: var(--color-text);
}

.philosophy-intro h2 .accent {
    color: var(--color-accent);
}

.philosophy-intro p {
    font-size: 15px;
    line-height: 1.8;
    color: var(--color-text-light);
    text-align: justify;
    margin-bottom: 0;
}

/* Hero Section */
.hero {
    padding: var(--spacing-2xl) var(--spacing-xl);
    text-align: center;
    background: linear-gradient(135deg, #f8f8f6 0%, #f0f0ed 100%);
    min-height: calc(100vh - 80px);
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-content {
    max-width: 700px;
    animation: fadeInUp 0.8s ease-out;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero h1 {
    font-size: clamp(32px, 8vw, 56px);
    font-weight: 800;
    color: var(--color-text);
    margin-bottom: var(--spacing-md);
    line-height: 1.2;
}

.hero .accent {
    color: var(--color-primary);
}

.hero p {
    font-size: 18px;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-2xl);
    line-height: 1.8;
}

.hero-buttons {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: var(--spacing-2xl);
}

.btn {
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: 16px;
    border-radius: var(--border-radius);
    border: none;
    cursor: pointer;
    font-weight: 600;
    transition: var(--transition);
    text-decoration: none;
    display: inline-block;
}

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

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

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

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

.hero-image {
    margin-top: var(--spacing-2xl);
    opacity: 0.9;
}

.hero-image svg {
    width: 100%;
    max-width: 400px;
    height: auto;
}

/* Features Section */
.features {
    padding: var(--spacing-2xl) var(--spacing-xl);
    background-color: var(--color-white);
}

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

.section-title {
    font-size: clamp(28px, 6vw, 42px);
    font-weight: 700;
    text-align: center;
    margin-bottom: var(--spacing-2xl);
    color: var(--color-text);
}

.section-subtitle {
    text-align: center;
    color: var(--color-text-light);
    font-size: 16px;
    margin-bottom: var(--spacing-2xl);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-2xl);
}

.feature-card {
    background-color: var(--color-bg);
    padding: var(--spacing-xl);
    border-radius: var(--border-radius);
    text-align: center;
    transition: var(--transition);
    border: 1px solid transparent;
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: var(--color-primary);
}

.feature-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto var(--spacing-md);
    font-size: 28px;
}

.feature-card h3 {
    font-size: 18px;
    margin-bottom: var(--spacing-sm);
    color: var(--color-text);
}

.feature-card p {
    color: var(--color-text-light);
    font-size: 14px;
    line-height: 1.6;
}

/* How It Works Section */
.how-it-works {
    padding: var(--spacing-2xl) var(--spacing-xl);
    background: linear-gradient(135deg, #f8f8f6 0%, #f0f0ed 100%);
}

.how-it-works-container {
    max-width: 1000px;
    margin: 0 auto;
}

.steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-2xl);
}

.step {
    text-align: center;
    position: relative;
}

.step-number {
    display: inline-flex;
    width: 50px;
    height: 50px;
    background-color: var(--color-primary);
    color: var(--color-white);
    border-radius: 50%;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

.step h3 {
    font-size: 16px;
    margin-bottom: var(--spacing-sm);
    color: var(--color-text);
}

.step p {
    font-size: 14px;
    color: var(--color-text-light);
    line-height: 1.6;
}

.step::after {
    content: '→';
    position: absolute;
    right: -20px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 24px;
    color: var(--color-primary);
    display: none;
}

@media (min-width: 768px) {
    .step::after {
        display: block;
    }

    .steps > :last-child::after {
        display: none;
    }
}

/* Loading spinner */
.spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: var(--color-white);
    animation: spin 1s ease-in-out infinite;
}

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

/* Utility classes */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
}

.text-center {
    text-align: center;
}

.mt-2xl {
    margin-top: var(--spacing-2xl);
}

.mb-2xl {
    margin-bottom: var(--spacing-2xl);
}

/* Toast Notifications */
.toast {
    position: fixed;
    bottom: var(--spacing-lg);
    right: var(--spacing-lg);
    padding: var(--spacing-md) var(--spacing-lg);
    background-color: var(--color-success);
    color: var(--color-white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-lg);
    animation: slideIn 0.3s ease-out;
    z-index: 2000;
    max-width: 400px;
}

.toast.error {
    background-color: var(--color-error);
}

.toast.warning {
    background-color: var(--color-warning);
}

@keyframes slideIn {
    from {
        transform: translateX(400px);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* Responsive Design */
@media (max-width: 768px) {
    nav {
        padding: var(--spacing-md) var(--spacing-lg);
        flex-wrap: wrap;
        gap: var(--spacing-lg);
    }

    .nav-links {
        gap: var(--spacing-lg);
        flex-wrap: wrap;
        justify-content: center;
    }

    .logo {
        flex: 1 1 100%;
        justify-content: center;
        order: -1;
    }

    .philosophy-intro {
        padding: var(--spacing-xl) var(--spacing-md);
    }

    .philosophy-intro h2 {
        font-size: 20px;
        margin-bottom: var(--spacing-md);
    }

    .philosophy-intro p {
        font-size: 14px;
        text-align: left;
    }

    .hero {
        padding: var(--spacing-xl) var(--spacing-md);
        min-height: auto;
    }

    .hero h1 {
        font-size: 28px;
    }

    .hero p {
        font-size: 15px;
    }

    .hero-buttons {
        flex-direction: column;
        gap: var(--spacing-sm);
    }

    .btn {
        width: 100%;
    }

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

    .feature-card {
        padding: var(--spacing-lg);
    }

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

    .step::after {
        display: none;
    }

    .step-number {
        width: 45px;
        height: 45px;
        font-size: 20px;
    }
}

/* Small devices (below 480px) */
@media (max-width: 480px) {
    .nav-links {
        gap: var(--spacing-md);
    }

    .philosophy-intro {
        padding: var(--spacing-lg) var(--spacing-sm);
    }

    .philosophy-intro h2 {
        font-size: 18px;
        margin-bottom: var(--spacing-sm);
    }

    .philosophy-intro p {
        font-size: 13px;
    }

    .hero {
        padding: var(--spacing-lg) var(--spacing-sm);
    }

    .hero h1 {
        font-size: 24px;
        margin-bottom: var(--spacing-sm);
    }

    .hero p {
        font-size: 14px;
        margin-bottom: var(--spacing-lg);
    }

    .section-title {
        font-size: 24px;
        margin-bottom: var(--spacing-lg);
    }
}