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

:root {
    --primary-color: #0066cc;
    --secondary-color: #ff6b35;
    --dark-bg: #1a1a2e;
    --light-bg: #f5f7fa;
    --text-dark: #2d3748;
    --text-light: #ffffff;
    --border-color: #e2e8f0;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --max-width: 1200px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--light-bg);
}

/* Header & Navigation */
.header {
    background-color: var(--dark-bg);
    color: var(--text-light);
    padding: 1rem 2rem;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo a {
    font-size: 1.5rem;
    font-weight: bold;
    text-decoration: none;
}

.logo-any {
    color: var(--text-light);
}

.logo-vec {
    color: #8B0000;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-links a {
    color: var(--text-light);
    text-decoration: none;
    transition: color 0.3s;
}

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

.menu-toggle,
.menu-close {
    display: none;
    background: none;
    border: none;
    color: var(--text-light);
    font-size: 1.5rem;
    cursor: pointer;
}

.lang-switcher a {
    padding: 0.5rem 1rem;
    background-color: var(--primary-color);
    color: var(--text-light);
    text-decoration: none;
    border-radius: 4px;
    transition: background-color 0.3s;
}

.lang-switcher a:hover {
    background-color: var(--secondary-color);
}

/* Main Content */
.main-content {
    min-height: calc(100vh - 200px);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--dark-bg) 0%, var(--primary-color) 100%);
    color: var(--text-light);
    padding: 4rem 2rem;
    text-align: center;
}

.hero-content {
    max-width: var(--max-width);
    margin: 0 auto;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.tagline {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--secondary-color);
}

.description {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.cta-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* Buttons */
.btn {
    padding: 0.75rem 1.5rem;
    border-radius: 4px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    display: inline-block;
    cursor: pointer;
    border: none;
}

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

.btn-primary:hover {
    background-color: #0052a3;
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.btn-primary:disabled {
    background-color: #cccccc;
    cursor: not-allowed;
    transform: none;
}

.btn-secondary {
    background-color: var(--secondary-color);
    color: var(--text-light);
}

.btn-secondary:hover {
    background-color: #e55a2b;
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

/* Sections */
.services-preview,
.services-detailed,
.team-section,
.github-projects,
.page-header,
.contact-section,
.cta-section {
    max-width: var(--max-width);
    margin: 3rem auto;
    padding: 0 2rem;
}

.page-header {
    text-align: center;
    margin-bottom: 3rem;
}

.page-header h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
}

/* Services */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.service-card, .service-item {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
    transition: transform 0.3s;
}

.service-card:hover, .service-item:hover {
    transform: translateY(-5px);
}

.service-card h3, .service-item h2 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.services-list {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.cta-center {
    text-align: center;
    margin-top: 3rem;
}

/* Team */
.team-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
}

.team-card {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
}

.team-card h2 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.bio {
    margin-bottom: 1.5rem;
}

.skills h3 {
    font-size: 1rem;
    margin-bottom: 0.5rem;
    color: var(--text-dark);
}

.skill-list {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.skill-tag {
    background-color: var(--primary-color);
    color: var(--text-light);
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
}

.social-links {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.social-links a {
    color: var(--primary-color);
    transition: color 0.3s;
}

.social-links a:hover {
    color: var(--secondary-color);
}

/* Contact */
.contact-container {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 3rem;
}

.contact-info, .contact-form-container {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
}

.contact-info h2, .contact-form-container h2 {
    margin-bottom: 1rem;
}

.info-item {
    margin-bottom: 1.5rem;
}

.info-item h3 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

/* Forms */
.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text-dark);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 2px solid var(--border-color);
    border-radius: 4px;
    font-family: inherit;
    font-size: 1rem;
    transition: all 0.3s ease;
    background-color: #ffffff;
}

/* Hide placeholder text visually (we use it only for :placeholder-shown selector) */
.form-group input::placeholder,
.form-group textarea::placeholder {
    color: transparent;
}

/* Default state: no special border when empty or pristine */
.form-group input:placeholder-shown,
.form-group textarea:placeholder-shown {
    border-color: var(--border-color);
}

/* Hover state for empty fields */
.form-group input:hover:placeholder-shown,
.form-group textarea:hover:placeholder-shown {
    border-color: #cbd5e0;
}

/* Focus state - primary color */
.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 102, 204, 0.1);
}

/* Invalid state - red border when field has content but is invalid */
.form-group input:invalid:not(:placeholder-shown):not(:focus),
.form-group textarea:invalid:not(:placeholder-shown):not(:focus) {
    border-color: #dc3545;
    box-shadow: 0 0 0 3px rgba(220, 53, 69, 0.1);
}

/* Valid state - green border when field has valid content */
.form-group input:valid:not(:placeholder-shown):not(:focus),
.form-group textarea:valid:not(:placeholder-shown):not(:focus) {
    border-color: #28a745;
    box-shadow: 0 0 0 3px rgba(40, 167, 69, 0.1);
}

/* Manual validation classes for phone field */
.form-group input.manual-valid {
    border-color: #28a745 !important;
    box-shadow: 0 0 0 3px rgba(40, 167, 69, 0.1) !important;
}

.form-group input.manual-invalid {
    border-color: #dc3545 !important;
    box-shadow: 0 0 0 3px rgba(220, 53, 69, 0.1) !important;
}

/* Keep phone field neutral when empty (no validation classes) */
.form-group input[type="tel"]:not(.manual-valid):not(.manual-invalid):placeholder-shown {
    border-color: var(--border-color);
    box-shadow: none;
}

/* Override default valid/invalid styling for phone field since we handle it manually */
.form-group input[type="tel"]:valid:not(:placeholder-shown):not(:focus),
.form-group input[type="tel"]:invalid:not(:placeholder-shown):not(:focus) {
    border-color: var(--border-color);
    box-shadow: none;
}

.contact-form-container form {
    display: flex;
    flex-direction: column;
}

.contact-form-container form button[type="submit"] {
    align-self: center;
    min-width: 200px;
    margin-top: 1rem;
}

.form-message {
    margin-bottom: 1rem;
    padding: 0.75rem;
    border-radius: 4px;
}

.form-message.success {
    background-color: #d4edda;
    color: #155724;
}

.form-message.error {
    background-color: #f8d7da;
    color: #721c24;
}

/* Footer */
.footer {
    background-color: var(--dark-bg);
    color: var(--text-light);
    padding: 3rem 2rem 1rem;
    margin-top: 4rem;
}

.footer-content {
    max-width: var(--max-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3 {
    margin-bottom: 1rem;
}

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

.footer-section a {
    color: var(--text-light);
    text-decoration: none;
    transition: color 0.3s;
}

.footer-section a:hover {
    color: var(--secondary-color);
}

.footer-bottom {
    max-width: var(--max-width);
    margin: 0 auto;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
}

/* CTA Section */
.cta-section {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: var(--text-light);
    padding: 3rem 2rem;
    border-radius: 8px;
    text-align: center;
}

.cta-section h2 {
    margin-bottom: 1rem;
}

/* Loading */
.loading {
    text-align: center;
    padding: 2rem;
    color: var(--text-dark);
}

/* Error Message */
.error-message {
    text-align: center;
    padding: 2rem;
    background-color: #fff3cd;
    border: 1px solid #ffc107;
    border-radius: 8px;
    margin: 2rem 0;
}

.error-message p {
    color: #856404;
    margin: 0;
}

.error-message a {
    color: var(--primary-color);
    text-decoration: underline;
    font-weight: bold;
}

.error-message a:hover {
    color: var(--secondary-color);
}

/* Responsive */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background-color: var(--dark-bg);
        flex-direction: column;
        padding: 1rem;
        box-shadow: var(--shadow);
    }

    .nav-links.active {
        display: flex;
    }

    .menu-toggle,
    .menu-close {
        display: block;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .tagline {
        font-size: 1.25rem;
    }

    .contact-container {
        grid-template-columns: 1fr;
    }

    .cta-buttons {
        flex-direction: column;
        align-items: center;
    }
}

@media (max-width: 480px) {
    .hero h1 {
        font-size: 1.75rem;
    }

    .services-grid,
    .team-grid {
        grid-template-columns: 1fr;
    }
}