/* ================================================
   TECHBLOOMAI - Clean, Refined Design
   Inspired by claude.ai aesthetic
   ================================================ */

/* ===== CSS Variables ===== */
:root {
    /* Modern purple/blue gradient palette - TechbloomAI brand colors */
    --color-bg-primary: #FAF9FF;
    --color-bg-secondary: #F3F0FF;
    --color-bg-tertiary: #E9E5FF;
    --color-text-primary: #1A1A2E;
    --color-text-secondary: #4A4A5A;
    --color-text-tertiary: #9CA3AF;

    /* Brand gradient colors */
    --color-accent: #667eea;
    --color-accent-secondary: #764ba2;
    --color-accent-light: #EEEDFF;
    --color-accent-lighter: #F5F3FF;

    /* Gradient definitions */
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-subtle: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
    --gradient-hover: linear-gradient(135deg, #7C8FF5 0%, #8B5BB8 100%);

    --color-border: #E5E7EB;
    --color-surface: #FFFFFF;

    /* Semantic colors with purple accents */
    --color-success: #10B981;
    --color-warning: #F59E0B;
    --color-error: #EF4444;
    --color-info: #3B82F6;

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

    /* Spacing scale */
    --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: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -1px rgba(0, 0, 0, 0.04);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -2px rgba(0, 0, 0, 0.04);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.08), 0 10px 10px -5px rgba(0, 0, 0, 0.03);

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

    /* Container widths */
    --container-sm: 640px;
    --container-md: 768px;
    --container-lg: 1024px;
    --container-xl: 1280px;
    --container-2xl: 1536px;
}

/* ===== Reset & Base ===== */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-text-primary);
    background-color: var(--color-surface);
    overflow-x: hidden;
}

/* Import Inter font */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap');

/* ===== Container ===== */
.container {
    width: 100%;
    max-width: var(--container-xl);
    margin: 0 auto;
    padding: 0 var(--space-6);
}

@media (min-width: 768px) {
    .container {
        padding: 0 var(--space-8);
    }
}

/* ===== Navigation ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid #E7E5E4;
    transition: background var(--transition-base), box-shadow var(--transition-base);
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.98);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.nav-brand h1 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--color-text-primary);
    letter-spacing: -0.02em;
}

.nav-brand .highlight {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: var(--space-8);
    list-style: none;
}

.nav-menu a {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text-secondary);
    text-decoration: none;
    transition: color var(--transition-fast);
    position: relative;
}

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

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

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

/* Active navigation link state */
.nav-menu a.active {
    color: var(--color-accent);
    font-weight: 600;
}

.cta-btn {
    padding: var(--space-2) var(--space-5) !important;
    background: var(--gradient-primary) !important;
    color: var(--color-surface) !important;
    border-radius: var(--radius-full) !important;
    transition: all var(--transition-base) !important;
    box-shadow: 0 2px 8px rgba(102, 126, 234, 0.25);
}

.cta-btn:hover {
    background: var(--gradient-hover) !important;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.35);
}

.hamburger {
    display: none;
    flex-direction: column;
    gap: var(--space-1);
    padding: var(--space-2);
    background: none;
    border: none;
    cursor: pointer;
}

.hamburger span {
    width: 24px;
    height: 2px;
    background: var(--color-text-primary);
    border-radius: var(--radius-full);
    transition: all var(--transition-base);
}

/* ===== Hero Section ===== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 64px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 800px;
    height: 800px;
    background: radial-gradient(circle, rgba(102, 126, 234, 0.08) 0%, transparent 70%);
    border-radius: 50%;
    pointer-events: none;
}

.hero-content {
    position: relative;
    max-width: 720px;
    margin: 0 auto;
    text-align: center;
}

.hero-buttons {
    position: relative;
    display: flex;
    justify-content: center;
}

.hero-buttons {
    position: relative;
}

.hero-stats {
    position: relative;
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 3.75rem);
    font-weight: 700;
    line-height: 1.15;
    letter-spacing: -0.03em;
    color: #FFFFFF;
    margin-bottom: var(--space-6);
    text-shadow: none;
    -webkit-text-stroke: 0;
}

.hero-title .gradient-text {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.125rem;
    line-height: 1.7;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: var(--space-10);
    margin-left: auto;
    margin-right: auto;
    max-width: 540px;
}

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

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-3) var(--space-6);
    font-size: 0.9375rem;
    font-weight: 500;
    text-decoration: none;
    border-radius: var(--radius-lg);
    transition: all var(--transition-base);
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: var(--gradient-primary);
    color: var(--color-surface);
    box-shadow: 0 2px 8px rgba(102, 126, 234, 0.2);
}

.btn-primary:hover {
    background: var(--gradient-hover);
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(102, 126, 234, 0.3);
}

.btn-secondary {
    background: var(--color-surface);
    color: #000000;
    border: 1px solid var(--color-border);
}

.btn-secondary:hover {
    border-color: #000000;
    background: var(--color-bg-secondary);
}

.btn-block {
    width: 100%;
}

/* ===== Hero Stats ===== */
.hero-stats {
    display: flex;
    gap: var(--space-12);
    margin-top: var(--space-16);
    justify-content: center;
    text-align: center;
}

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

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: #FFFFFF;
    line-height: 1;
}

.stat-label {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.8);
    margin-top: var(--space-2);
}

/* ===== Section Base ===== */
section {
    padding: var(--space-24) 0;
}

.section-header {
    text-align: center;
    margin-bottom: var(--space-16);
    max-width: 640px;
    margin-left: auto;
    margin-right: auto;
}

.section-title {
    font-size: clamp(2rem, 4vw, 2.75rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    color: #000000;
    margin-bottom: var(--space-4);
}

.section-subtitle {
    font-size: 1.0625rem;
    color: var(--color-text-secondary);
    line-height: 1.6;
}

/* ===== About Section ===== */
.about {
    background: var(--color-bg-secondary);
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
}

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

@media (min-width: 1024px) {
    .about-grid {
        grid-template-columns: 1fr 1fr;
    }
}

.about-content h3 {
    font-size: 1.75rem;
    font-weight: 600;
    letter-spacing: -0.02em;
    color: #000000;
    margin-bottom: var(--space-6);
}

.about-content p {
    font-size: 1.0625rem;
    line-height: 1.75;
    color: var(--color-text-secondary);
    margin-bottom: var(--space-4);
}

.about-highlights {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
    margin-top: var(--space-8);
}

.highlight-item {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    font-size: 0.9375rem;
    color: var(--color-text-secondary);
}

.highlight-icon {
    width: 24px;
    height: 24px;
    background: var(--color-accent-light);
    color: var(--color-accent);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.75rem;
    font-weight: 600;
    flex-shrink: 0;
}

.about-image {
    display: flex;
    justify-content: center;
}

.image-placeholder {
    width: 100%;
    max-width: 480px;
    border-radius: var(--radius-2xl);
    overflow: hidden;
    box-shadow: var(--shadow-xl);
}

.image-placeholder svg {
    width: 100%;
    height: auto;
    display: block;
}

/* ===== Services Section ===== */
.services {
    background: var(--color-surface);
}

.service-category {
    margin-bottom: var(--space-20);
}

.category-header {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    margin-bottom: var(--space-8);
    padding-bottom: var(--space-6);
    border-bottom: 1px solid var(--color-border);
}

.category-icon {
    font-size: 1.75rem;
}

.category-header h3 {
    font-size: 1.5rem;
    font-weight: 600;
    letter-spacing: -0.02em;
    color: #000000;
}

.service-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--space-6);
}

.service-card {
    background: var(--color-surface);
    padding: var(--space-8);
    border-radius: var(--radius-xl);
    border: 1px solid var(--color-border);
    transition: all var(--transition-base);
}

.service-card:hover {
    border-color: var(--color-accent);
    box-shadow: 0 10px 25px -5px rgba(102, 126, 234, 0.15);
    transform: translateY(-4px);
}

.service-icon {
    font-size: 2rem;
    margin-bottom: var(--space-4);
    display: inline-block;
}

.service-card h4 {
    font-size: 1.25rem;
    font-weight: 600;
    letter-spacing: -0.02em;
    color: #000000;
    margin-bottom: var(--space-3);
}

.service-card p {
    font-size: 0.9375rem;
    line-height: 1.65;
    color: var(--color-text-secondary);
    margin-bottom: var(--space-6);
}

.service-features {
    list-style: none;
}

.service-features li {
    padding: var(--space-2) 0;
    font-size: 0.875rem;
    color: var(--color-text-secondary);
    display: flex;
    align-items: flex-start;
    gap: var(--space-2);
}

.service-features li::before {
    content: '•';
    color: var(--color-accent);
    font-weight: 600;
}

/* ===== Why Us Section ===== */
.why-us {
    background: linear-gradient(135deg, #1A1A2E 0%, #2D2B42 100%);
    color: var(--color-surface);
    position: relative;
}

.why-us::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(ellipse at top right, rgba(102, 126, 234, 0.15) 0%, transparent 50%);
    pointer-events: none;
}

.why-us .section-title,
.why-us .section-subtitle {
    color: var(--color-surface);
}

.why-us .section-subtitle {
    opacity: 0.9;
}

.why-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: var(--space-6);
}

.why-card {
    background: rgba(255, 255, 255, 0.05);
    padding: var(--space-8);
    border-radius: var(--radius-xl);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: all var(--transition-base);
}

.why-card:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(255, 255, 255, 0.2);
}

.why-number {
    font-size: 2rem;
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: var(--space-4);
}

.why-card h3 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: var(--space-3);
}

.why-card p {
    font-size: 0.9375rem;
    line-height: 1.65;
    color: rgba(255, 255, 255, 0.7);
}

/* ===== Industries Section ===== */
.industries {
    background: var(--color-bg-secondary);
}

.industry-list {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-3);
    justify-content: center;
    max-width: 800px;
    margin: 0 auto;
}

.industry-item {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-5);
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text-secondary);
    transition: all var(--transition-base);
}

.industry-item:hover {
    border-color: var(--color-accent);
    background: var(--color-accent-lighter);
    color: var(--color-accent);
    transform: translateY(-1px);
}

/* ===== Contact Section ===== */
.contact {
    background: var(--color-surface);
}

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

@media (min-width: 1024px) {
    .contact-grid {
        grid-template-columns: 1fr 1fr;
    }
}

.contact-info h3 {
    font-size: 1.75rem;
    font-weight: 600;
    letter-spacing: -0.02em;
    color: #000000;
    margin-bottom: var(--space-4);
}

.contact-info > p {
    font-size: 1.0625rem;
    line-height: 1.7;
    color: var(--color-text-secondary);
    margin-bottom: var(--space-10);
}

.contact-details {
    display: flex;
    flex-direction: column;
    gap: var(--space-6);
}

.contact-item {
    display: flex;
    gap: var(--space-4);
    align-items: flex-start;
}

.contact-icon {
    width: 48px;
    height: 48px;
    background: var(--color-bg-secondary);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    flex-shrink: 0;
}

.contact-item-content h4 {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: #78716C;
    margin-bottom: var(--space-1);
}

.contact-item-content p {
    font-size: 0.9375rem;
    font-weight: 500;
    color: #000000;
}

/* ===== Contact Form ===== */
.contact-form-wrapper {
    background: var(--color-bg-secondary);
    padding: var(--space-8);
    border-radius: var(--radius-2xl);
    border: 1px solid var(--color-border);
}

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

/* ===== Security: Honeypot Field ===== */
/* Hide honeypot field from legitimate users */
.form-group[style*="display:none"] {
    position: absolute;
    left: -10000px;
    top: auto;
    width: 1px;
    height: 1px;
    overflow: hidden;
}

/* Additional honeypot hiding for screen readers */
.form-group[style*="display:none"] * {
    display: none;
}

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

.form-group label {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text-secondary);
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: var(--space-3) var(--space-4);
    font-size: 0.9375rem;
    font-family: inherit;
    color: #000000;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    transition: all var(--transition-fast);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.15);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: var(--color-text-tertiary);
}

.form-group select {
    cursor: pointer;
}

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

/* ===== Footer ===== */
.footer {
    background: var(--color-text-primary);
    color: var(--color-surface);
    padding: var(--space-16) 0 var(--space-8);
}

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

@media (min-width: 769px) {
    .footer-content {
        grid-template-columns: 2fr 1fr 1fr 1fr;
    }
}

.footer-brand h3 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: var(--space-3);
}

.footer-brand .highlight {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.footer-brand p {
    font-size: 0.9375rem;
    color: rgba(255, 255, 255, 0.7);
    max-width: 280px;
    line-height: 1.6;
}

.footer-links h4 {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: rgba(255, 255, 255, 0.5);
    margin-bottom: var(--space-4);
}

.footer-links ul {
    list-style: none;
}

.footer-links li {
    margin-bottom: var(--space-3);
}

.footer-links a {
    font-size: 0.9375rem;
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: #A78BFA;
}

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

.social-links a {
    display: inline-flex;
    align-items: center;
    padding: var(--space-2) var(--space-4);
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.social-links a:hover {
    background: rgba(255, 255, 255, 0.1);
    color: var(--color-surface);
}

.footer-bottom {
    padding-top: var(--space-8);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
}

.footer-bottom p {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.5);
}

/* ===== Scroll Progress Bar ===== */
.progress-bar {
    position: fixed;
    top: 0;
    left: 0;
    height: 3px;
    background: var(--gradient-primary);
    z-index: 10001;
    transition: width 0.1s ease;
    box-shadow: 0 0 10px rgba(102, 126, 234, 0.5);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 64px;
        left: 0;
        right: 0;
        flex-direction: column;
        background: var(--color-surface);
        padding: var(--space-6);
        border-bottom: 1px solid var(--color-border);
        transform: translateY(-100%);
        opacity: 0;
        transition: all var(--transition-base);
        pointer-events: none;
        gap: var(--space-4);
    }

    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        pointer-events: auto;
    }

    .hamburger {
        display: flex;
    }

    .hamburger.active span:nth-child(1) {
        transform: translateY(6px) rotate(45deg);
    }

    .hamburger.active span:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active span:nth-child(3) {
        transform: translateY(-6px) rotate(-45deg);
    }

    .hero {
        padding-top: var(--space-12);
        text-align: center;
    }

    .hero-content {
        margin: 0 auto;
    }

    .hero-subtitle {
        margin-left: auto;
        margin-right: auto;
    }

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

    .hero-stats {
        flex-direction: column;
        gap: var(--space-8);
        text-align: center;
        align-items: center;
    }

    .stat-number {
        font-size: 2rem;
    }

    section {
        padding: var(--space-16) 0;
    }

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

    .footer-content {
        grid-template-columns: 1fr 1fr;
        text-align: center;
    }

    .footer-brand p {
        margin: 0 auto;
    }

    .social-links {
        align-items: center;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }

    .hero-buttons {
        flex-direction: column;
        width: 100%;
    }

    .btn {
        width: 100%;
    }

    .footer-content {
        grid-template-columns: 1fr;
    }

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

/* ===== Utilities ===== */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* ===== Selection ===== */
::selection {
    background: var(--color-accent-light);
    color: var(--color-text-primary);
}

/* ===== Focus visible ===== */
:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
    box-shadow: 0 0 0 4px rgba(102, 126, 234, 0.15);
}

/* ===== Smooth scroll offset ===== */
html {
    scroll-padding-top: 80px;
}

/* ===== Scroll to Top Button ===== */
.scroll-to-top {
    position: fixed;
    bottom: var(--space-6);
    right: var(--space-6);
    width: 48px;
    height: 48px;
    background: var(--gradient-primary);
    color: var(--color-surface);
    border: none;
    border-radius: var(--radius-full);
    font-size: 1.5rem;
    cursor: pointer;
    z-index: 999;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all var(--transition-base);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    justify-content: center;
}

.scroll-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.scroll-to-top:hover {
    background: var(--gradient-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
}

.scroll-to-top:focus {
    outline: 2px solid var(--color-text-primary);
    outline-offset: 2px;
}

.scroll-to-top:active {
    transform: translateY(0);
}

/* ===== Enhanced Active State for Sections ===== */
section:target {
    scroll-margin-top: 80px;
}

/* ===== Enhanced Focus Styles for Better Keyboard Navigation ===== */
a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

/* ===== Smooth Scroll Enhancements ===== */
@media (prefers-reduced-motion: no-preference) {
    html {
        scroll-behavior: smooth;
    }
}

/* Respect reduced motion preference */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }

    html {
        scroll-behavior: auto;
    }
}