/* ============================================
   14th International Scientific Conference
   Modern CSS Styling
   ============================================ */

:root {
    --primary-color: #003D7A;
    --secondary-color: #17A2B8;
    --accent-color: #FFC107;
    --text-dark: #1a1a1a;
    --text-light: #666666;
    --bg-light: #f5f5f5;
    --border-color: #e0e0e0;
    --white: #ffffff;
    --spacing-unit: 1rem;
}

/* Reset & Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Lato', sans-serif;
    color: var(--text-dark);
    line-height: 1.6;
    background-color: var(--white);
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Merriweather', serif;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

p {
    margin-bottom: 1rem;
    color: var(--text-light);
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color 0.3s ease;
}

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

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 1rem;
}


/* ============================================
   HEADER & NAVIGATION
   ============================================ */

.header {
    background-color: var(--white);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 4px solid var(--primary-color);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: 1rem;
    text-decoration: none;
    color: var(--primary-color);
}

.logo-circle {
    width: 50px;
    height: 50px;
    background-color: var(--primary-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-weight: bold;
    font-size: 1.25rem;
}

.logo-text h1 {
    font-size: 0.9rem;
    margin: 0;
    line-height: 1.2;
}

.logo-text p {
    font-size: 0.75rem;
    margin: 0;
    color: var(--text-light);
}

.nav-desktop {
    display: flex;
    gap: 0.5rem;
    align-items: center;
}

.nav-link {
    padding: 0.75rem 1rem;
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-dark);
    border-radius: 0.5rem;
    transition: all 0.3s ease;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
    background-color: rgba(0, 61, 122, 0.05);
}

.btn-register {
    padding: 0.75rem 1.5rem;
    background-color: var(--accent-color);
    color: var(--text-dark);
    font-weight: 600;
    border-radius: 0.5rem;
    transition: all 0.3s ease;
}

.btn-register:hover {
    background-color: #ffb300;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(255, 193, 7, 0.3);
}

.menu-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    gap: 0.4rem;
}

.menu-toggle span {
    width: 25px;
    height: 3px;
    background-color: var(--primary-color);
    border-radius: 2px;
    transition: all 0.3s ease;
}

.nav-mobile {
    display: none;
    flex-direction: column;
    gap: 0.5rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
}

.nav-link-mobile {
    padding: 0.75rem 1rem;
    color: var(--text-dark);
    font-weight: 500;
    transition: all 0.3s ease;
}

.nav-link-mobile:hover {
    color: var(--primary-color);
    padding-left: 1.5rem;
}

.btn-register-mobile {
    padding: 0.75rem 1rem;
    background-color: var(--accent-color);
    color: var(--text-dark);
    font-weight: 600;
    border-radius: 0.5rem;
    text-align: center;
    margin-top: 0.5rem;
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */

@media (max-width: 768px) {
    .nav-desktop,
    .btn-register {
        display: none;
    }

    .menu-toggle {
        display: flex;
    }

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

    h1 { font-size: 2rem; }
    h2 { font-size: 1.5rem; }
    h3 { font-size: 1.25rem; }
}

/* ============================================
   HERO SECTION
   ============================================ */

.hero {
    position: relative;
    color: var(--white);
    padding: 6rem 2rem;
    text-align: center;
    min-height: 500px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.hero-slider {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
}

.hero-slider .slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
    opacity: 0;
    transition: opacity 1.5s ease-in-out;
}

.hero-slider .slide::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(rgba(0, 61, 122, 0.6), rgba(0, 61, 122, 0.6));
}

.hero-slider .slide.active {
    opacity: 1;
}

.hero .container {
    position: relative;
    z-index: 2;
}

.hero-content h1 {
    color: var(--white);
    font-size: 3.5rem;
    margin-bottom: 1rem;
    text-shadow: 2px 2px 8px rgba(0, 0, 0, 0.5);
}

.hero-content p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 1.25rem;
    margin-bottom: 2rem;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.3);
}

.hero-info {
    display: flex;
    justify-content: center;
    gap: 3rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.hero-info-item {
    text-align: center;
}

.hero-info-item i {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

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

.btn {
    padding: 0.75rem 2rem;
    font-size: 1rem;
    font-weight: 600;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-block;
}

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

.btn-primary:hover {
    background-color: #ffb300;
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(255, 193, 7, 0.4);
}

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

.btn-secondary:hover {
    background-color: rgba(255, 255, 255, 0.9);
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(255, 255, 255, 0.4);
}

/* ============================================
   SECTIONS
   ============================================ */

section {
    padding: 4rem 2rem;
}

section.bg-light {
    background-color: var(--bg-light);
}

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

section.bg-primary h2,
section.bg-primary h3 {
    color: var(--white);
}

section.bg-primary p {
    color: rgba(255, 255, 255, 0.9);
}

.section-title {
    text-align: center;
    margin-bottom: 3rem;
}

/* ============================================
   CARDS & GRID
   ============================================ */
.card-grid2 {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
        gap: 20px;
    }

.card2 {
        display: flex;
        align-items: center;
        gap: 15px;
        padding: 20px;
        border: 1px solid #ddd;
        border-radius: 12px;
        background: #fff;
        box-shadow: 0 2px 8px rgba(0,0,0,0.05);
    }

.card2 img {
        width: 90px;
        height: 90px;
        object-fit: cover;
        border-radius: 10px;
        flex-shrink: 0;
    }

.card-content2 h4 {
        margin: 0 0 8px;
    }

.card-content2 p {
        margin: 4px 0;
    }
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.card {
    background-color: var(--white);
    border-radius: 0.75rem;
    padding: 2rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
}

.card:hover {
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
    transform: translateY(-4px);
}

.card-icon {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.card h3 {
    margin-bottom: 1rem;
}

.card p {
    color: var(--text-light);
    font-size: 0.95rem;
}

/* ============================================
   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,
.form-group select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    font-family: inherit;
    font-size: 1rem;
    transition: all 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 61, 122, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 150px;
}

.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1rem;
}

.form-container {
    max-width: 600px;
    margin: 0 auto;
    background-color: var(--white);
    padding: 2rem;
    border-radius: 0.75rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

/* ============================================
   COUNTDOWN TIMER
   ============================================ */

.countdown-section {
    background-color: var(--white);
    padding: 3rem 0;
    border-bottom: 1px solid var(--border-color);
}

#countdown {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.countdown-item {
    background: var(--primary-color);
    color: var(--white);
    padding: 1.5rem;
    border-radius: 0.75rem;
    min-width: 120px;
    text-align: center;
    box-shadow: 0 4px 12px rgba(0, 61, 122, 0.2);
}

.countdown-value {
    font-size: 2.5rem;
    font-weight: 700;
    line-height: 1;
    margin-bottom: 0.5rem;
}

.countdown-label {
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    opacity: 0.8;
}

/* ============================================
   FOOTER
   ============================================ */

.footer {
    background-color: var(--primary-color);
    color: var(--white);
    padding: 3rem 2rem 1rem;
    margin-top: 4rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3,
.footer-section h4 {
    color: var(--white);
    margin-bottom: 1rem;
}

.footer-section p {
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.95rem;
}

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

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: rgba(255, 255, 255, 0.8);
    transition: color 0.3s ease;
}

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

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

.social-icon {
    width: 40px;
    height: 40px;
    background-color: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
}

.social-icon:hover {
    background-color: var(--accent-color);
    color: var(--text-dark);
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    padding-top: 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.footer-links {
    display: flex;
    gap: 2rem;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.9rem;
}

/* ============================================
   UTILITIES
   ============================================ */

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

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

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

.text-accent {
    color: var(--accent-color);
}

.mt-1 { margin-top: 1rem; }
.mt-2 { margin-top: 2rem; }
.mt-3 { margin-top: 3rem; }

.mb-1 { margin-bottom: 1rem; }
.mb-2 { margin-bottom: 2rem; }
.mb-3 { margin-bottom: 3rem; }

.pt-1 { padding-top: 1rem; }
.pt-2 { padding-top: 2rem; }
.pt-3 { padding-top: 3rem; }

.pb-1 { padding-bottom: 1rem; }
.pb-2 { padding-bottom: 2rem; }
.pb-3 { padding-bottom: 3rem; }

/* ============================================
   ANIMATIONS
   ============================================ */

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.6s ease-out;
}

/* ============================================
   ALERTS & MESSAGES
   ============================================ */

.alert {
    padding: 1rem;
    border-radius: 0.5rem;
    margin-bottom: 1rem;
}

.alert-success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.alert-error {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.alert-info {
    background-color: #d1ecf1;
    color: #0c5460;
    border: 1px solid #bee5eb;
}

/* ============================================
   TIMELINE
   ============================================ */

.timeline {
    position: relative;
    padding: 2rem 0;
}

.timeline-item {
    margin-bottom: 2rem;
    padding-left: 3rem;
    position: relative;
}

.timeline-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    width: 20px;
    height: 20px;
    background-color: var(--primary-color);
    border-radius: 50%;
    border: 4px solid var(--white);
    box-shadow: 0 0 0 2px var(--primary-color);
}

.timeline-item.accent::before {
    background-color: var(--accent-color);
    box-shadow: 0 0 0 2px var(--accent-color);
}

.timeline-item::after {
    content: '';
    position: absolute;
    left: 9px;
    top: 20px;
    width: 2px;
    height: calc(100% + 1rem);
    background-color: var(--border-color);
}

.timeline-item:last-child::after {
    display: none;
}

.timeline-date {
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.timeline-content {
    background-color: var(--bg-light);
    padding: 1.5rem;
    border-radius: 0.5rem;
}

/* ============================================
   PRICING TABLE
   ============================================ */

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.pricing-card {
    background-color: var(--white);
    border: 2px solid var(--border-color);
    border-radius: 0.75rem;
    padding: 2rem;
    text-align: center;
    transition: all 0.3s ease;
}

.pricing-card:hover {
    border-color: var(--primary-color);
    box-shadow: 0 8px 24px rgba(0, 61, 122, 0.15);
    transform: translateY(-4px);
}

.pricing-card.featured {
    border-color: var(--accent-color);
    background-color: rgba(255, 193, 7, 0.05);
}

.pricing-title {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.pricing-price {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--accent-color);
    margin-bottom: 1rem;
}

.pricing-features {
    list-style: none;
    margin-bottom: 2rem;
    text-align: left;
}

.pricing-features li {
    padding: 0.5rem 0;
    border-bottom: 1px solid var(--border-color);
    color: var(--text-light);
}

.pricing-features li::before {
    content: '✓ ';
    color: var(--accent-color);
    font-weight: bold;
    margin-right: 0.5rem;
}