/* ===================================
   GLOBAL STYLES & RESET
   =================================== */
:root {
    --primary-color: #0066FF;
    --primary-dark: #0052CC;
    --primary-light: #3385FF;
    --secondary-color: #00D9FF;
    --accent-color: #FF6B35;
    --success-color: #00C48C;
    --warning-color: #FFA400;
    --danger-color: #FF3B3B;
    
    --text-primary: #1A1A2E;
    --text-secondary: #4A4A68;
    --text-light: #8A8AA0;
    
    --bg-primary: #FFFFFF;
    --bg-secondary: #F8F9FF;
    --bg-dark: #0F1419;
    --bg-card: #FFFFFF;
    
    --gradient-primary: linear-gradient(135deg, #0066FF 0%, #00D9FF 100%);
    --gradient-secondary: linear-gradient(135deg, #FF6B35 0%, #FFA400 100%);
    --gradient-dark: linear-gradient(135deg, #1A1A2E 0%, #16213E 100%);
    
    --shadow-sm: 0 2px 8px rgba(0, 102, 255, 0.08);
    --shadow-md: 0 4px 16px rgba(0, 102, 255, 0.12);
    --shadow-lg: 0 8px 32px rgba(0, 102, 255, 0.16);
    --shadow-xl: 0 16px 48px rgba(0, 102, 255, 0.24);
    
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    
    --transition-fast: 0.2s ease;
    --transition-base: 0.3s ease;
    --transition-slow: 0.5s ease;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    color: var(--text-primary);
    background: var(--bg-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

section {
    padding: 100px 0;
    position: relative;
}

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

a {
    text-decoration: none;
    color: inherit;
}

/* ===================================
   TYPOGRAPHY
   =================================== */
h1, h2, h3, h4, h5, h6 {
    font-family: 'Space Grotesk', 'Inter', sans-serif;
    font-weight: 700;
    line-height: 1.2;
    color: var(--text-primary);
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 800;
    margin-bottom: 24px;
}

.section-title {
    font-size: clamp(2rem, 4vw, 3rem);
    margin-bottom: 16px;
}

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

/* ===================================
   NAVIGATION
   =================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-md);
    transition: var(--transition-base);
    border-bottom: 1px solid rgba(0, 102, 255, 0.1);
}

.navbar.scrolled {
    box-shadow: var(--shadow-lg);
    background: rgba(255, 255, 255, 1);
}

.nav-wrapper {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
    gap: 40px;
    min-height: 100px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 20px;
    font-family: 'Space Grotesk', sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    flex-shrink: 0;
    text-decoration: none;
    cursor: pointer;
    transition: var(--transition-fast);
}

.logo:hover {
    opacity: 0.8;
}

.logo:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 4px;
    border-radius: 4px;
}

.logo-image {
    height: auto;
    max-height: 80px;
    width: auto;
    max-width: 280px;
    object-fit: contain;
    transition: var(--transition-fast);
    display: block;
}

.logo-image:hover {
    transform: scale(1.05);
}

.logo span {
    white-space: nowrap;
    line-height: 1.2;
    background: linear-gradient(135deg, #1a1a1a 0%, #333333 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 700;
}

.logo i {
    font-size: 1.75rem;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 28px;
    align-items: center;
    margin: 0;
    flex-wrap: wrap;
}

.nav-link {
    font-weight: 500;
    color: var(--text-secondary);
    transition: var(--transition-fast);
    position: relative;
}

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

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: var(--transition-fast);
}

.nav-link:hover::after {
    width: 100%;
}

.btn-nav {
    padding: 10px 20px;
    background: var(--gradient-primary);
    color: white !important;
    border-radius: var(--radius-sm);
    font-weight: 600;
}

.btn-nav::after {
    display: none;
}

.mobile-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
}

.mobile-toggle span {
    width: 24px;
    height: 3px;
    background: var(--primary-color);
    border-radius: 2px;
    transition: var(--transition-fast);
}

/* ===================================
   BUTTONS
   =================================== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    border: none;
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all var(--transition-base);
    text-align: center;
    justify-content: center;
}

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: var(--shadow-md);
}

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

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

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

.btn-block {
    width: 100%;
}

/* ===================================
   HERO SECTION
   =================================== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    padding-top: 140px;
    overflow: hidden;
}

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

.animated-gradient {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #F8F9FF 0%, #E8F0FF 50%, #F0F8FF 100%);
    animation: gradientShift 15s ease infinite;
}

@keyframes gradientShift {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.8; }
}

.particles {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-text {
    z-index: 10;
}

.badge {
    display: inline-block;
    padding: 8px 16px;
    background: white;
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--primary-color);
    box-shadow: var(--shadow-sm);
    margin-bottom: 24px;
}

.hero-description {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 40px;
    line-height: 1.8;
}

.hero-stats {
    display: flex;
    gap: 48px;
    margin-bottom: 40px;
}

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

.stat-number {
    font-size: 3rem;
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1;
}

.stat-number::after {
    content: '+';
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-light);
    margin-top: 8px;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.hero-visual {
    position: relative;
    height: 500px;
}

.floating-card {
    position: absolute;
    background: white;
    padding: 20px 24px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: 12px;
    animation: float 6s ease-in-out infinite;
}

.floating-card i {
    font-size: 2rem;
    color: var(--primary-color);
}

.floating-card span {
    font-weight: 600;
    font-size: 0.95rem;
}

.card-1 {
    top: 10%;
    left: 5%;
    animation-delay: 0s;
}

.card-2 {
    top: 30%;
    right: 10%;
    animation-delay: 1.5s;
}

.card-3 {
    bottom: 30%;
    left: 15%;
    animation-delay: 3s;
}

.card-4 {
    bottom: 10%;
    right: 5%;
    animation-delay: 4.5s;
}

@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-20px); }
}

/* ===================================
   SECTION HEADERS
   =================================== */
.section-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 60px;
}

.section-badge {
    display: inline-block;
    padding: 8px 20px;
    background: var(--gradient-primary);
    color: white;
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 16px;
}

.section-description {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-top: 16px;
}

/* ===================================
   SERVICES SECTION
   =================================== */
.services {
    background: var(--bg-secondary);
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 32px;
}

.service-card {
    background: white;
    padding: 40px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
    border: 2px solid transparent;
}

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

.service-icon {
    width: 80px;
    height: 80px;
    background: var(--gradient-primary);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 24px;
    font-size: 2rem;
    color: white;
}

.service-card h3 {
    font-size: 1.5rem;
    margin-bottom: 16px;
    color: var(--text-primary);
}

.service-card p {
    color: var(--text-secondary);
    margin-bottom: 24px;
    line-height: 1.7;
}

.service-features {
    list-style: none;
    margin-bottom: 24px;
}

.service-features li {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 12px;
    color: var(--text-secondary);
}

.service-features i {
    color: var(--success-color);
    font-size: 1rem;
}

.service-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--primary-color);
    font-weight: 600;
    transition: var(--transition-fast);
}

.service-link:hover {
    gap: 12px;
}

/* ===================================
   ABOUT SECTION
   =================================== */
.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
}

.about-text p {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 20px;
    line-height: 1.8;
}

.about-values {
    margin: 40px 0;
}

.value-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    margin-bottom: 24px;
}

.value-item i {
    font-size: 1.5rem;
    color: var(--success-color);
    margin-top: 4px;
}

.value-item h4 {
    font-size: 1.125rem;
    margin-bottom: 4px;
}

.value-item p {
    font-size: 0.95rem;
    color: var(--text-light);
    margin: 0;
}

.tech-stack {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
}

.tech-item {
    background: white;
    padding: 24px;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-md);
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 600;
    transition: all var(--transition-base);
}

.tech-item:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.tech-item i {
    font-size: 2rem;
    color: var(--primary-color);
}

/* ===================================
   INTERACTIVE SECTION
   =================================== */
.interactive {
    background: var(--bg-secondary);
}

.subsection-title {
    font-size: 1.75rem;
    text-align: center;
    margin-bottom: 12px;
}

.subsection-description {
    text-align: center;
    color: var(--text-secondary);
    margin-bottom: 40px;
}

.flashcard-section {
    margin-bottom: 80px;
}

.flashcard-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 32px;
}

.flashcard {
    height: 300px;
    perspective: 1000px;
    cursor: pointer;
}

.flashcard-inner {
    position: relative;
    width: 100%;
    height: 100%;
    transition: transform 0.6s;
    transform-style: preserve-3d;
}

.flashcard.flipped .flashcard-inner {
    transform: rotateY(180deg);
}

.flashcard-front,
.flashcard-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    border-radius: var(--radius-lg);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 32px;
    box-shadow: var(--shadow-lg);
}

.flashcard-front {
    background: white;
    border: 2px solid var(--primary-light);
}

.flashcard-front i {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 16px;
}

.flashcard-front h4 {
    font-size: 1.25rem;
    text-align: center;
    margin-bottom: 12px;
}

.tap-hint {
    font-size: 0.875rem;
    color: var(--text-light);
    text-align: center;
}

.flashcard-back {
    background: var(--gradient-primary);
    color: white;
    transform: rotateY(180deg);
}

.flashcard-back p {
    text-align: center;
    line-height: 1.8;
    font-size: 1rem;
}

/* ===================================
   CALCULATOR SECTION
   =================================== */
.calculator-section {
    margin-bottom: 80px;
}

.calculator-card {
    background: white;
    border-radius: var(--radius-xl);
    padding: 48px;
    box-shadow: var(--shadow-lg);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 48px;
}

.form-group {
    margin-bottom: 32px;
}

.form-group label {
    display: block;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.form-group input[type="range"] {
    width: 100%;
    height: 8px;
    background: var(--bg-secondary);
    border-radius: 4px;
    outline: none;
    -webkit-appearance: none;
}

.form-group input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 24px;
    height: 24px;
    background: var(--gradient-primary);
    border-radius: 50%;
    cursor: pointer;
    box-shadow: var(--shadow-md);
}

.form-group input[type="range"]::-moz-range-thumb {
    width: 24px;
    height: 24px;
    background: var(--gradient-primary);
    border-radius: 50%;
    cursor: pointer;
    border: none;
    box-shadow: var(--shadow-md);
}

.range-value {
    display: inline-block;
    min-width: 50px;
    padding: 4px 12px;
    background: var(--gradient-primary);
    color: white;
    border-radius: var(--radius-sm);
    font-weight: 600;
    text-align: center;
    margin-top: 8px;
}

.checkbox-group {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.checkbox-group label {
    display: flex;
    align-items: center;
    gap: 12px;
    cursor: pointer;
    font-weight: 500;
}

.checkbox-group input[type="checkbox"] {
    width: 20px;
    height: 20px;
    cursor: pointer;
    accent-color: var(--primary-color);
}

.calculator-result {
    display: flex;
    align-items: center;
    justify-content: center;
}

.result-box {
    text-align: center;
    background: var(--bg-secondary);
    padding: 48px;
    border-radius: var(--radius-xl);
    width: 100%;
}

.result-label {
    display: block;
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 16px;
}

.result-amount {
    font-size: 4rem;
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 16px;
    line-height: 1;
}

.result-note {
    font-size: 0.875rem;
    color: var(--text-light);
    margin-bottom: 32px;
}

/* ===================================
   QUIZ SECTION
   =================================== */
.quiz-section {
    background: var(--gradient-dark);
    color: white;
}

.quiz-section .section-badge {
    background: rgba(255, 255, 255, 0.2);
    color: white;
}

.quiz-section .section-title,
.quiz-section .section-description {
    color: white;
}

.quiz-container {
    max-width: 800px;
    margin: 0 auto;
    background: white;
    border-radius: var(--radius-xl);
    padding: 48px;
    box-shadow: var(--shadow-xl);
}

.quiz-progress {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 40px;
}

.progress-bar {
    flex: 1;
    height: 8px;
    background: var(--bg-secondary);
    border-radius: 4px;
    margin-right: 20px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--gradient-primary);
    border-radius: 4px;
    transition: width var(--transition-base);
}

.progress-text {
    font-weight: 600;
    color: var(--text-secondary);
    white-space: nowrap;
}

.question-card {
    margin-bottom: 40px;
}

.question-text {
    font-size: 1.5rem;
    color: var(--text-primary);
    margin-bottom: 32px;
}

.answers-grid {
    display: grid;
    gap: 16px;
}

.answer-option {
    padding: 20px 24px;
    background: var(--bg-secondary);
    border: 2px solid transparent;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    font-weight: 500;
    color: var(--text-primary);
}

.answer-option:hover {
    border-color: var(--primary-light);
    background: white;
}

.answer-option.selected {
    border-color: var(--primary-color);
    background: var(--primary-color);
    color: white;
}

.answer-option.correct {
    border-color: var(--success-color);
    background: var(--success-color);
    color: white;
}

.answer-option.incorrect {
    border-color: var(--danger-color);
    background: var(--danger-color);
    color: white;
}

.quiz-navigation {
    display: flex;
    justify-content: space-between;
    gap: 16px;
}

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

.result-content {
    padding: 40px;
}

.result-icon {
    font-size: 5rem;
    margin-bottom: 24px;
}

.result-content h3 {
    font-size: 2rem;
    color: var(--text-primary);
    margin-bottom: 16px;
}

.result-content p {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 32px;
}

.result-score {
    display: inline-block;
    padding: 24px 48px;
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    margin-bottom: 32px;
}

.score-text {
    display: block;
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.score-number {
    font-size: 3rem;
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.result-actions {
    display: flex;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
}

/* ===================================
   TESTIMONIALS SECTION
   =================================== */
.testimonials {
    background: white;
}

.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 32px;
}

.testimonial-card {
    background: var(--bg-secondary);
    padding: 40px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
}

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

.stars {
    color: var(--warning-color);
    font-size: 1.25rem;
    margin-bottom: 16px;
}

.testimonial-card p {
    font-size: 1.05rem;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 24px;
    font-style: italic;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: 16px;
}

.author-avatar {
    width: 50px;
    height: 50px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 700;
    font-size: 1.125rem;
}

.testimonial-author h4 {
    font-size: 1rem;
    margin-bottom: 4px;
}

.testimonial-author span {
    font-size: 0.875rem;
    color: var(--text-light);
}

/* ===================================
   CONTACT SECTION
   =================================== */
.contact {
    background: var(--bg-secondary);
}

.contact-wrapper {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 60px;
}

.contact-info h2 {
    margin-bottom: 20px;
}

.contact-info > p {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 40px;
    line-height: 1.8;
}

.contact-details {
    margin-bottom: 40px;
}

.contact-item {
    display: flex;
    gap: 20px;
    margin-bottom: 32px;
}

.contact-item i {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-top: 4px;
}

.contact-item h4 {
    font-size: 1.125rem;
    margin-bottom: 8px;
}

.contact-item p {
    color: var(--text-secondary);
    line-height: 1.6;
}

.social-links {
    display: flex;
    gap: 16px;
}

.social-link {
    width: 48px;
    height: 48px;
    background: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    color: var(--primary-color);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-fast);
}

.social-link:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
    background: var(--gradient-primary);
    color: white;
}

.contact-form-wrapper {
    background: white;
    padding: 48px;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
}

.contact-form .form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

.contact-form .form-group {
    margin-bottom: 24px;
}

.contact-form label {
    display: block;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text-primary);
}

.contact-form input,
.contact-form select,
.contact-form textarea {
    width: 100%;
    padding: 14px 16px;
    border: 2px solid var(--bg-secondary);
    border-radius: var(--radius-md);
    font-family: inherit;
    font-size: 1rem;
    transition: all var(--transition-fast);
    background: white;
}

.contact-form input:focus,
.contact-form select:focus,
.contact-form textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 4px rgba(0, 102, 255, 0.1);
}

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

.form-message {
    margin-top: 16px;
    padding: 16px;
    border-radius: var(--radius-md);
    font-weight: 500;
    display: none;
    animation: slideDown 0.3s ease;
    font-size: 0.95rem;
    line-height: 1.5;
}

.form-message.success {
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
    display: block;
}

.form-message.error {
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
    display: block;
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.contact-form input.error,
.contact-form select.error,
.contact-form textarea.error {
    border-color: #dc3545;
    background-color: #fff5f5;
}

.contact-form input.error:focus,
.contact-form select.error:focus,
.contact-form textarea.error:focus {
    border-color: #dc3545;
    box-shadow: 0 0 0 3px rgba(220, 53, 69, 0.1);
}

.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    pointer-events: none;
}

/* ===================================
   FOOTER
   =================================== */
.footer {
    background: var(--bg-dark);
    color: white;
    padding: 80px 0 24px;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1.5fr;
    gap: 48px;
    margin-bottom: 48px;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-family: 'Space Grotesk', sans-serif;
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 16px;
    text-decoration: none;
    color: inherit;
    cursor: pointer;
    transition: var(--transition-fast);
    width: fit-content;
}

.footer-logo:hover {
    opacity: 0.8;
    transform: translateX(3px);
}

.footer-logo:focus {
    outline: 2px solid var(--primary-light);
    outline-offset: 4px;
    border-radius: 4px;
}

.footer-logo-image {
    height: auto;
    max-height: 60px;
    width: auto;
    max-width: 200px;
    object-fit: contain;
    filter: brightness(0) invert(1);
    transition: var(--transition-fast);
}

.footer-logo-image:hover {
    transform: scale(1.05);
}

.footer-logo i {
    font-size: 1.75rem;
    color: var(--primary-light);
}

.footer-section p {
    color: rgba(255, 255, 255, 0.7);
    line-height: 1.8;
}

.footer-section h4 {
    color: white;
    margin-bottom: 20px;
    font-size: 1.125rem;
}

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

.footer-section ul li {
    margin-bottom: 12px;
}

.footer-section ul li a {
    color: rgba(255, 255, 255, 0.7);
    transition: var(--transition-fast);
}

.footer-section ul li a:hover {
    color: var(--primary-light);
    padding-left: 4px;
}

.newsletter-form {
    display: flex;
    margin-top: 16px;
}

.newsletter-form input {
    flex: 1;
    padding: 12px 16px;
    border: 2px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-md) 0 0 var(--radius-md);
    background: rgba(255, 255, 255, 0.1);
    color: white;
    font-family: inherit;
}

.newsletter-form input::placeholder {
    color: rgba(255, 255, 255, 0.5);
}

.newsletter-form button {
    padding: 12px 20px;
    background: var(--gradient-primary);
    border: none;
    border-radius: 0 var(--radius-md) var(--radius-md) 0;
    color: white;
    cursor: pointer;
    transition: var(--transition-fast);
}

.newsletter-form button:hover {
    opacity: 0.9;
}

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 32px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.6);
}

.footer-links {
    display: flex;
    gap: 24px;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.6);
    transition: var(--transition-fast);
}

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

/* ===================================
   RESPONSIVE DESIGN
   =================================== */
@media (max-width: 1024px) {
    .hero-content {
        grid-template-columns: 1fr;
    }
    
    .hero-visual {
        display: none;
    }
    
    .about-content {
        grid-template-columns: 1fr;
    }
    
    .calculator-card {
        grid-template-columns: 1fr;
    }
    
    .contact-wrapper {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    section {
        padding: 60px 0;
    }
    
    .mobile-toggle {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        top: 120px;
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        padding: 24px;
        box-shadow: var(--shadow-lg);
        transform: translateX(-100%);
        transition: var(--transition-base);
    }
    
    .nav-menu.active {
        transform: translateX(0);
    }
    
    .logo-image {
        max-height: 60px;
        max-width: 200px;
    }
    
    .logo {
        gap: 16px;
    }
    
    .logo span {
        font-size: 1.2rem;
    }
    
    .nav-wrapper {
        padding: 15px 0;
        min-height: 80px;
    }
    
    .hero {
        padding-top: 110px;
    }
    
    .nav-menu {
        top: 95px;
    }
    
    .hero-stats {
        gap: 24px;
    }
    
    .stat-number {
        font-size: 2rem;
    }
    
    .hero-buttons {
        flex-direction: column;
    }
    
    .hero-buttons .btn {
        width: 100%;
    }
    
    .services-grid {
        grid-template-columns: 1fr;
    }
    
    .flashcard-container {
        grid-template-columns: 1fr;
    }
    
    .testimonials-grid {
        grid-template-columns: 1fr;
    }
    
    .contact-form .form-row {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
    }
    
    .footer-logo-image {
        max-height: 50px;
        max-width: 160px;
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: 16px;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }
    
    .logo-image {
        max-height: 45px;
        max-width: 150px;
    }
    
    .logo span {
        font-size: 0.95rem;
    }
    
    .nav-wrapper {
        min-height: 70px;
        padding: 12px 0;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 1.75rem;
    }
    
    .service-card,
    .contact-form-wrapper,
    .calculator-card,
    .quiz-container {
        padding: 24px;
    }
    
    .result-amount {
        font-size: 3rem;
    }
    
    .footer-logo-image {
        max-height: 40px;
        max-width: 130px;
    }
}

/* ===================================
   DARK THEME SUPPORT
   =================================== */
@media (prefers-color-scheme: dark) {
    /* Logo will automatically adapt if it has transparent background */
    /* For logos with white elements, they'll remain visible */
    /* Footer logo already has invert filter for white background */
}

/* ===================================
   ANIMATIONS & UTILITIES
   =================================== */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

[data-aos] {
    opacity: 0;
    transition: all 0.6s ease;
}

[data-aos].aos-animate {
    opacity: 1;
}

[data-aos="fade-up"].aos-animate {
    transform: translateY(0);
}

/* Smooth scrolling for all browsers */
@media (prefers-reduced-motion: no-preference) {
    html {
        scroll-behavior: smooth;
    }
}
