/* ChronoMedAI Website Styles */
/* Based on Design System v1.0 */

/* ==========================================================================
   CSS Variables (Design System Tokens)
   ========================================================================== */

:root {
    /* Primary Colors */
    --primary-50: #E8F4F8;
    --primary-100: #C1E4EF;
    --primary-200: #96D3E5;
    --primary-300: #6BC2DB;
    --primary-400: #4BB5D4;
    --primary-500: #2AA8CD;
    --primary-600: #2598BE;
    --primary-700: #1F84AA;
    --primary-800: #197196;
    --primary-900: #0F5070;

    /* Secondary Colors */
    --secondary-50: #EEF4F9;
    --secondary-100: #D4E3F0;
    --secondary-500: #71A2CD;
    --secondary-600: #699AC8;
    --secondary-700: #5E90C1;

    /* Neutral Colors */
    --neutral-50: #F8FAFB;
    --neutral-100: #F1F4F7;
    --neutral-200: #E4E9ED;
    --neutral-300: #D1D9E0;
    --neutral-400: #A8B5C3;
    --neutral-500: #8191A5;
    --neutral-600: #5B6B7D;
    --neutral-700: #3D4E5F;
    --neutral-800: #2B3745;
    --neutral-900: #1A232E;

    /* Semantic Colors */
    --success-50: #E8F7F0;
    --success-500: #10B981;
    --success-700: #047857;

    --warning-50: #FFF7ED;
    --warning-500: #F59E0B;
    --warning-700: #B45309;

    --error-50: #FEF2F2;
    --error-500: #EF4444;
    --error-700: #B91C1C;

    /* Typography */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    --space-16: 4rem;
    --space-20: 5rem;
    --space-24: 6rem;

    /* Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;

    /* Shadows */
    --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);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 200ms ease;
    --transition-slow: 300ms ease;
}

/* ==========================================================================
   Reset & Base Styles
   ========================================================================== */

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-primary);
    font-size: 1rem;
    line-height: 1.6;
    color: var(--neutral-900);
    background: var(--neutral-50);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: var(--primary-600);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--primary-700);
}

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

/* ==========================================================================
   Layout
   ========================================================================== */

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-6);
}

/* ==========================================================================
   Header & Navigation
   ========================================================================== */

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--neutral-200);
    z-index: 1000;
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    color: var(--neutral-900);
    font-weight: 700;
    font-size: 1.25rem;
}

.logo:hover {
    color: var(--neutral-900);
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--primary-500), var(--secondary-500));
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
}

.logo-text {
    font-size: 1.375rem;
}

.nav-links {
    display: flex;
    gap: var(--space-8);
}

.nav-link {
    color: var(--neutral-600);
    font-weight: 500;
    font-size: 0.9375rem;
    transition: color var(--transition-fast);
}

.nav-link:hover {
    color: var(--neutral-900);
}

.nav-actions {
    display: flex;
    gap: var(--space-4);
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-2);
}

.mobile-menu-toggle span {
    width: 24px;
    height: 2px;
    background: var(--neutral-700);
    transition: var(--transition-fast);
}

.mobile-menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.mobile-menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.mobile-menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* ==========================================================================
   Buttons
   ========================================================================== */

.button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-6);
    border-radius: var(--radius-md);
    font-family: var(--font-primary);
    font-weight: 600;
    font-size: 0.9375rem;
    text-decoration: none;
    border: none;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.button-primary {
    background: var(--primary-500);
    color: white;
}

.button-primary:hover {
    background: var(--primary-600);
    color: white;
    box-shadow: var(--shadow-md);
    transform: translateY(-1px);
}

.button-outline {
    background: transparent;
    border: 2px solid var(--primary-500);
    color: var(--primary-500);
}

.button-outline:hover {
    background: var(--primary-50);
    color: var(--primary-600);
}

.button-lg {
    padding: var(--space-4) var(--space-8);
    font-size: 1rem;
}

.button-full {
    width: 100%;
}

/* ==========================================================================
   Hero Section
   ========================================================================== */

.hero {
    padding: calc(72px + var(--space-20)) 0 var(--space-20);
    background: linear-gradient(180deg, var(--neutral-50) 0%, white 100%);
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-16);
    align-items: center;
}

.hero-content {
    max-width: 560px;
}

.hero-title {
    font-size: 3rem;
    font-weight: 700;
    line-height: 1.15;
    color: var(--neutral-900);
    margin-bottom: var(--space-6);
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--neutral-600);
    line-height: 1.6;
    margin-bottom: var(--space-8);
}

.hero-actions {
    display: flex;
    gap: var(--space-4);
    flex-wrap: wrap;
}

.hero-visual {
    display: flex;
    justify-content: center;
}

.hero-card {
    background: white;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    padding: var(--space-6);
    width: 100%;
    max-width: 400px;
    border: 1px solid var(--neutral-200);
}

.timeline-preview {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
}

.timeline-item {
    display: flex;
    gap: var(--space-4);
    padding: var(--space-3) 0;
    border-left: 3px solid var(--primary-500);
    padding-left: var(--space-4);
}

.timeline-date {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--primary-600);
    white-space: nowrap;
    min-width: 100px;
}

.timeline-event {
    font-size: 0.9375rem;
    color: var(--neutral-700);
}

/* ==========================================================================
   Sections Common Styles
   ========================================================================== */

.section-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto var(--space-12);
}

.section-title {
    font-size: 2.25rem;
    font-weight: 700;
    color: var(--neutral-900);
    margin-bottom: var(--space-4);
}

.section-subtitle {
    font-size: 1.125rem;
    color: var(--neutral-600);
    line-height: 1.6;
}

/* ==========================================================================
   Features Section
   ========================================================================== */

.features {
    padding: var(--space-24) 0;
    background: white;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-8);
}

.feature-card {
    background: var(--neutral-50);
    border-radius: var(--radius-xl);
    padding: var(--space-8);
    transition: all var(--transition-normal);
}

.feature-card:hover {
    background: white;
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
}

.feature-icon {
    width: 56px;
    height: 56px;
    background: var(--primary-100);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary-600);
    margin-bottom: var(--space-5);
}

.feature-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--neutral-900);
    margin-bottom: var(--space-3);
}

.feature-description {
    color: var(--neutral-600);
    line-height: 1.6;
}

/* ==========================================================================
   How It Works Section
   ========================================================================== */

.how-it-works {
    padding: var(--space-24) 0;
    background: var(--neutral-50);
}

.steps-grid {
    display: flex;
    align-items: flex-start;
    justify-content: center;
    gap: var(--space-4);
}

.step-card {
    flex: 1;
    max-width: 320px;
    text-align: center;
    padding: var(--space-6);
}

.step-number {
    width: 64px;
    height: 64px;
    background: var(--primary-500);
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
    color: white;
    margin: 0 auto var(--space-5);
}

.step-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--neutral-900);
    margin-bottom: var(--space-3);
}

.step-description {
    color: var(--neutral-600);
    line-height: 1.6;
}

.step-connector {
    width: 80px;
    height: 2px;
    background: var(--neutral-300);
    margin-top: 32px;
    flex-shrink: 0;
}

/* ==========================================================================
   Contact Section
   ========================================================================== */

.contact {
    padding: var(--space-24) 0;
    background: white;
}

.contact-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-16);
    align-items: start;
}

.contact-info .section-title {
    text-align: left;
}

.contact-info .section-subtitle {
    text-align: left;
    margin-bottom: var(--space-8);
}

.contact-details {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
}

.contact-item {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    color: var(--neutral-600);
}

.contact-item svg {
    color: var(--primary-500);
    flex-shrink: 0;
}

.contact-item a {
    color: var(--neutral-700);
}

.contact-form-wrapper {
    background: var(--neutral-50);
    border-radius: var(--radius-xl);
    padding: var(--space-8);
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: var(--space-5);
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.form-label {
    font-weight: 500;
    font-size: 0.9375rem;
    color: var(--neutral-700);
}

.form-input,
.form-textarea {
    padding: var(--space-3) var(--space-4);
    border: 1px solid var(--neutral-300);
    border-radius: var(--radius-md);
    font-family: var(--font-primary);
    font-size: 1rem;
    color: var(--neutral-900);
    background: white;
    transition: all var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--primary-500);
    box-shadow: 0 0 0 3px var(--primary-100);
}

.form-textarea {
    resize: vertical;
    min-height: 120px;
}

.form-status {
    padding: var(--space-3);
    border-radius: var(--radius-md);
    font-size: 0.9375rem;
    text-align: center;
    display: none;
}

.form-status.success {
    display: block;
    background: var(--success-50);
    color: var(--success-700);
}

.form-status.error {
    display: block;
    background: var(--error-50);
    color: var(--error-700);
}

/* ==========================================================================
   Footer
   ========================================================================== */

.footer {
    background: var(--neutral-900);
    color: var(--neutral-300);
    padding: var(--space-16) 0 var(--space-8);
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: var(--space-16);
    margin-bottom: var(--space-12);
}

.footer-brand .logo {
    color: white;
    margin-bottom: var(--space-4);
}

.footer-brand .logo:hover {
    color: white;
}

.footer-brand .logo-icon {
    background: var(--primary-500);
}

.footer-tagline {
    color: var(--neutral-400);
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-8);
}

.footer-column {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
}

.footer-heading {
    color: white;
    font-weight: 600;
    font-size: 0.9375rem;
    margin-bottom: var(--space-2);
}

.footer-column a {
    color: var(--neutral-400);
    font-size: 0.9375rem;
    transition: color var(--transition-fast);
}

.footer-column a:hover {
    color: white;
}

.footer-bottom {
    padding-top: var(--space-8);
    border-top: 1px solid var(--neutral-700);
    text-align: center;
    font-size: 0.875rem;
    color: var(--neutral-500);
}

/* ==========================================================================
   Responsive Design
   ========================================================================== */

@media (max-width: 1024px) {
    .hero .container {
        grid-template-columns: 1fr;
        gap: var(--space-12);
    }

    .hero-content {
        max-width: 100%;
        text-align: center;
    }

    .hero-actions {
        justify-content: center;
    }

    .hero-title {
        font-size: 2.5rem;
    }

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

    .contact-wrapper {
        grid-template-columns: 1fr;
        gap: var(--space-12);
    }

    .contact-info .section-title,
    .contact-info .section-subtitle {
        text-align: center;
    }

    .contact-details {
        align-items: center;
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: var(--space-12);
        text-align: center;
    }

    .footer-brand {
        display: flex;
        flex-direction: column;
        align-items: center;
    }

    .footer-links {
        justify-content: center;
    }

    .footer-column {
        align-items: center;
    }
}

@media (max-width: 768px) {
    .nav-links,
    .nav-actions {
        display: none;
    }

    .nav-links.active {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: white;
        padding: var(--space-6);
        border-bottom: 1px solid var(--neutral-200);
        box-shadow: var(--shadow-lg);
    }

    .nav-links.active .nav-link {
        padding: var(--space-3) 0;
    }

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

    .hero-title {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1.125rem;
    }

    .section-title {
        font-size: 1.75rem;
    }

    .steps-grid {
        flex-direction: column;
        align-items: center;
    }

    .step-connector {
        width: 2px;
        height: 40px;
        margin: 0;
    }

    .footer-links {
        grid-template-columns: 1fr;
        gap: var(--space-8);
    }
}

/* ==========================================================================
   Utility Classes
   ========================================================================== */

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}