/* ===========================
   Global Variables & Reset
   =========================== */
:root {
    /* Primary Colors - Ocean Blue Theme */
    --primary-color: #0066cc;
    --primary-dark: #004c99;
    --primary-light: #3385d6;
    
    /* Secondary Colors - Navy & Teal */
    --secondary-color: #1a365d;
    --secondary-dark: #0f2744;
    --accent-color: #00b4d8;
    --accent-light: #48cae4;
    
    /* Neutral Colors */
    --white: #ffffff;
    --light-bg: #f8fafc;
    --light-gray: #e2e8f0;
    --medium-gray: #94a3b8;
    --dark-gray: #475569;
    --text-dark: #1e293b;
    
    /* Functional Colors */
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    
    /* Spacing */
    --section-padding: 100px;
    --container-max-width: 1200px;
    
    /* Typography */
    --font-primary: 'Noto Sans KR', sans-serif;
    --font-secondary: 'Roboto', sans-serif;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    
    /* Shadows */
    --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
    --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);
}

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

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

body {
    font-family: var(--font-primary);
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--white);
    overflow-x: hidden;
}

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

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition-normal);
}

ul {
    list-style: none;
}

button {
    border: none;
    background: none;
    cursor: pointer;
    font-family: inherit;
}

/* ===========================
   Utility Classes
   =========================== */
.container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 20px;
}

.section {
    padding: var(--section-padding) 0;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-subtitle {
    display: inline-block;
    font-size: 0.875rem;
    font-weight: 600;
    letter-spacing: 2px;
    text-transform: uppercase;
    color: var(--primary-color);
    margin-bottom: 15px;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--secondary-color);
    margin-bottom: 20px;
    line-height: 1.2;
}

.section-description {
    font-size: 1.125rem;
    color: var(--dark-gray);
    max-width: 600px;
    margin: 0 auto;
}

/* Button Styles */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    font-size: 1rem;
    font-weight: 500;
    border-radius: 8px;
    transition: var(--transition-normal);
    cursor: pointer;
}

.btn i {
    font-size: 1rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: var(--white);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    background: linear-gradient(135deg, var(--primary-dark), var(--secondary-dark));
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

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

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

.btn-block {
    width: 100%;
    justify-content: center;
}

/* ===========================
   Navigation
   =========================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: var(--white);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    transition: var(--transition-normal);
}

.navbar.scrolled {
    box-shadow: var(--shadow-md);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--secondary-color);
}

.logo-img {
    width: 50px;
    height: 50px;
    object-fit: contain;
}

.logo-full {
    height: 65px;
    width: auto;
    max-width: 400px;
    object-fit: contain;
}

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

.mobile-menu-btn {
    display: none;
    font-size: 1.5rem;
    color: var(--secondary-color);
}

.nav-menu {
    display: flex;
    gap: 35px;
    align-items: center;
}

.nav-link {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-dark);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: var(--transition-normal);
}

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

.nav-link-cta {
    padding: 10px 24px;
    background: var(--primary-color);
    color: var(--white);
    border-radius: 6px;
}

.nav-link-cta::after {
    display: none;
}

.nav-link-cta:hover {
    background: var(--primary-dark);
}

/* ===========================
   Hero Section
   =========================== */
.hero {
    position: relative;
    height: 100vh;
    min-height: 700px;
    background: linear-gradient(135deg, var(--secondary-dark) 0%, var(--secondary-color) 50%, var(--primary-dark) 100%);
    background-image: 
        linear-gradient(rgba(0, 30, 60, 0.7), rgba(0, 60, 120, 0.7)),
        url('../images/hero-bg-new.jpg');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 10%;
    right: 15%;
    width: 180px;
    height: 80px;
    backdrop-filter: blur(20px);
    z-index: 1;
    pointer-events: none;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at center, transparent 0%, rgba(0, 20, 40, 0.4) 100%);
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    color: var(--white);
    padding: 0 20px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 900;
    margin-bottom: 25px;
    line-height: 1.2;
    text-shadow: 2px 2px 10px rgba(0, 0, 0, 0.3);
}

.hero-subtitle {
    font-size: 1.25rem;
    margin-bottom: 60px;
    opacity: 0.95;
    font-weight: 300;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    margin-bottom: 35px;
    flex-wrap: wrap;
}

.hero-features {
    display: flex;
    gap: 50px;
    justify-content: center;
    flex-wrap: wrap;
}

.feature-item {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1rem;
}

.feature-item i {
    font-size: 1.5rem;
    color: var(--accent-light);
}

/* ===========================
   About Section
   =========================== */
.about-section {
    background: var(--light-bg);
}

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

.about-image {
    position: relative;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: var(--shadow-xl);
}

.about-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.about-badge {
    position: absolute;
    bottom: 30px;
    right: 30px;
    background: var(--primary-color);
    color: var(--white);
    padding: 20px 30px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 600;
    box-shadow: var(--shadow-lg);
}

.about-badge i {
    font-size: 1.5rem;
}

.about-text h3 {
    font-size: 1.75rem;
    color: var(--secondary-color);
    margin-bottom: 20px;
    font-weight: 700;
}

.about-text p {
    font-size: 1.05rem;
    color: var(--dark-gray);
    margin-bottom: 25px;
    line-height: 1.8;
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin: 40px 0;
    padding: 40px 0;
    border-top: 2px solid var(--light-gray);
    border-bottom: 2px solid var(--light-gray);
}

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

.stat-number {
    font-size: 2.25rem;
    font-weight: 900;
    color: var(--primary-color);
    margin-bottom: 8px;
}

.stat-label {
    font-size: 0.9rem;
    color: var(--medium-gray);
    font-weight: 500;
}

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

.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.service-card {
    background: var(--white);
    border: 1px solid var(--light-gray);
    border-radius: 12px;
    padding: 40px 30px;
    transition: var(--transition-normal);
}

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

.service-icon {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    color: var(--white);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    margin-bottom: 25px;
}

.service-title {
    font-size: 1.35rem;
    color: var(--secondary-color);
    margin-bottom: 15px;
    font-weight: 700;
}

.service-description {
    font-size: 1rem;
    color: var(--dark-gray);
    line-height: 1.7;
    margin-bottom: 20px;
}

.service-features {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.service-features li {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.95rem;
    color: var(--dark-gray);
}

.service-features i {
    color: var(--success);
    font-size: 0.875rem;
}

/* ===========================
   Safety Section
   =========================== */
.safety-section {
    background: linear-gradient(135deg, var(--secondary-dark) 0%, var(--secondary-color) 100%);
    color: var(--white);
}

.safety-section .section-subtitle {
    color: var(--accent-light);
}

.safety-section .section-title,
.safety-section .section-description {
    color: var(--white);
}

/* 안전 관리 설명 */
.safety-intro {
    background: rgba(255, 255, 255, 0.08);
    border-radius: 16px;
    padding: 50px;
    margin-bottom: 50px;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.safety-intro-content h3 {
    font-size: 2rem;
    color: var(--white);
    margin-bottom: 20px;
    font-weight: 700;
}

.safety-intro-content > p {
    font-size: 1.15rem;
    line-height: 1.8;
    color: rgba(255, 255, 255, 0.95);
    margin-bottom: 40px;
}

.safety-intro-content strong {
    color: var(--accent-light);
    font-weight: 700;
}

.safety-features {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
}

.safety-feature-item {
    display: flex;
    align-items: flex-start;
    gap: 20px;
    background: rgba(255, 255, 255, 0.05);
    padding: 25px;
    border-radius: 12px;
    transition: var(--transition-normal);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.safety-feature-item:hover {
    background: rgba(255, 255, 255, 0.1);
    transform: translateX(5px);
}

.safety-feature-item i {
    font-size: 2rem;
    color: var(--accent-light);
    min-width: 40px;
}

.safety-feature-item h4 {
    font-size: 1.1rem;
    color: var(--white);
    margin-bottom: 8px;
    font-weight: 600;
}

.safety-feature-item p {
    font-size: 0.95rem;
    color: rgba(255, 255, 255, 0.8);
    line-height: 1.6;
}

.certification-content {
    display: flex;
    flex-direction: column;
    gap: 60px;
}

.cert-section {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 16px;
    padding: 40px;
    backdrop-filter: blur(10px);
}

.cert-section-title {
    font-size: 1.75rem;
    color: var(--white);
    margin-bottom: 30px;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 15px;
}

.cert-section-title i {
    color: var(--accent-light);
}

/* ISO 인증 이미지 그리드 */
.cert-images-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.cert-images-grid.class-grid {
    grid-template-columns: repeat(4, 1fr);
}

.cert-image-card {
    background: var(--white);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    transition: var(--transition-normal);
}

.cert-image-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
}

.cert-image-card img {
    width: 100%;
    height: auto;
    display: block;
}

.cert-image-label {
    padding: 20px;
    text-align: center;
    background: var(--white);
    font-weight: 700;
    font-size: 1.1rem;
    color: var(--secondary-color);
    line-height: 1.4;
    min-height: 100px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

.cert-image-label span {
    display: block;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--dark-gray);
    margin-top: 5px;
}

/* 기타 자격 그리드 */
.qualifications-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 25px;
}

.qual-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 12px;
    padding: 30px;
    text-align: center;
    transition: var(--transition-normal);
}

.qual-card:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateY(-5px);
}

.qual-card i {
    font-size: 2.5rem;
    color: var(--accent-light);
    margin-bottom: 15px;
}

.qual-card h4 {
    font-size: 1.1rem;
    margin-bottom: 8px;
    font-weight: 600;
    color: var(--white);
}

.qual-card p {
    font-size: 0.875rem;
    opacity: 0.8;
    color: var(--white);
}

/* ===========================
   Field Sketch Section
   =========================== */
.field-sketch-section {
    background: var(--light-bg);
}

/* 카테고리 그리드 */
.field-categories-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
}

/* 카테고리 카드 */
.field-category-card {
    background: var(--white);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: var(--transition-normal);
}

.field-category-card:hover {
    box-shadow: var(--shadow-xl);
    transform: translateY(-8px);
}

/* 카테고리 헤더 */
.category-header {
    padding: 30px;
    text-align: center;
    background: linear-gradient(135deg, rgba(0, 102, 204, 0.05), rgba(0, 180, 216, 0.05));
}

.category-icon {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
}

.category-icon i {
    font-size: 2rem;
    color: var(--white);
}

.category-header h3 {
    font-size: 1.25rem;
    color: var(--secondary-color);
    margin-bottom: 10px;
    font-weight: 700;
    line-height: 1.4;
}

.category-header p {
    font-size: 0.95rem;
    color: var(--dark-gray);
    line-height: 1.6;
}

/* 카테고리 슬라이더 */
.category-slider-container {
    position: relative;
    width: 100%;
    height: 300px;
    overflow: hidden;
}

.category-slider {
    position: relative;
    width: 100%;
    height: 100%;
}

.slider-image {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 0.6s ease-in-out;
}

.slider-image.active {
    opacity: 1;
}

.slider-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* 슬라이더 버튼 */
.slider-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(255, 255, 255, 0.9);
    border: none;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    z-index: 10;
    transition: var(--transition-normal);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-md);
}

.slider-btn:hover {
    background: var(--primary-color);
    color: var(--white);
    transform: translateY(-50%) scale(1.1);
}

.slider-btn i {
    font-size: 1rem;
}

.prev-btn {
    left: 10px;
}

.next-btn {
    right: 10px;
}

/* 슬라이더 인디케이터 */
.slider-indicators {
    position: absolute;
    bottom: 15px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 8px;
    z-index: 10;
}

.indicator {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.5);
    cursor: pointer;
    transition: var(--transition-normal);
}

.indicator:hover {
    background: rgba(255, 255, 255, 0.8);
}

.indicator.active {
    background: var(--white);
    width: 28px;
    border-radius: 5px;
}

/* ===========================
   Portfolio Section
   =========================== */
.portfolio-section {
    background: var(--white);
}

.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.portfolio-card {
    background: var(--white);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: var(--transition-normal);
}

.portfolio-card:hover {
    box-shadow: var(--shadow-xl);
    transform: translateY(-8px);
}

.portfolio-image {
    position: relative;
    height: 250px;
    overflow: hidden;
}

.portfolio-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition-slow);
}

.portfolio-card:hover .portfolio-image img {
    transform: scale(1.1);
}

.portfolio-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to bottom, transparent 0%, rgba(0, 30, 60, 0.95) 100%);
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    padding: 25px;
    color: var(--white);
    opacity: 0;
    transition: var(--transition-normal);
}

.portfolio-card:hover .portfolio-overlay {
    opacity: 1;
}

.portfolio-overlay h3 {
    font-size: 1.25rem;
    margin-bottom: 8px;
    font-weight: 700;
}

.portfolio-overlay p {
    font-size: 0.95rem;
    opacity: 0.9;
}

.portfolio-info {
    padding: 25px;
}

.portfolio-info h3 {
    font-size: 1.15rem;
    color: var(--secondary-color);
    margin-bottom: 10px;
    font-weight: 700;
}

.portfolio-info > p {
    font-size: 0.95rem;
    color: var(--dark-gray);
    line-height: 1.6;
    margin-bottom: 15px;
}

.portfolio-tags {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.tag {
    display: inline-block;
    padding: 5px 12px;
    background: var(--light-bg);
    color: var(--primary-color);
    font-size: 0.8rem;
    font-weight: 500;
    border-radius: 20px;
}

/* ===========================
   Contact Section
   =========================== */
.contact-section {
    background: var(--light-bg);
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 60px;
}

.contact-info h3 {
    font-size: 1.75rem;
    color: var(--secondary-color);
    margin-bottom: 20px;
    font-weight: 700;
}

.contact-info > p {
    font-size: 1.05rem;
    color: var(--dark-gray);
    margin-bottom: 40px;
    line-height: 1.7;
}

.contact-details {
    display: flex;
    flex-direction: column;
    gap: 30px;
}

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

.contact-item i {
    font-size: 1.5rem;
    color: var(--primary-color);
    flex-shrink: 0;
}

.contact-item h4 {
    font-size: 1.1rem;
    color: var(--secondary-color);
    margin-bottom: 8px;
    font-weight: 600;
}

.contact-item p {
    font-size: 0.95rem;
    color: var(--dark-gray);
    line-height: 1.6;
}

.contact-form-wrapper {
    background: var(--white);
    padding: 40px;
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
}

.contact-form h3 {
    font-size: 1.5rem;
    color: var(--secondary-color);
    margin-bottom: 30px;
    font-weight: 700;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-dark);
    margin-bottom: 8px;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    font-size: 1rem;
    font-family: inherit;
    border: 2px solid var(--light-gray);
    border-radius: 8px;
    transition: var(--transition-normal);
}

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

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

/* ===========================
   Footer
   =========================== */
.footer {
    background: var(--secondary-dark);
    color: var(--white);
    padding: 60px 0 30px;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1.5fr;
    gap: 50px;
    margin-bottom: 40px;
}

.footer-section h4 {
    font-size: 1.15rem;
    margin-bottom: 20px;
    font-weight: 600;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 20px;
}

.footer-logo img {
    width: 60px;
    height: 60px;
    object-fit: contain;
}

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

.footer-section p {
    font-size: 0.95rem;
    line-height: 1.7;
    opacity: 0.85;
    margin-bottom: 20px;
}

.footer-social {
    display: flex;
    gap: 12px;
}

.footer-social a {
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition-normal);
}

.footer-social a:hover {
    background: var(--primary-color);
    transform: translateY(-3px);
}

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

.footer-section ul li a {
    font-size: 0.95rem;
    opacity: 0.85;
    transition: var(--transition-normal);
}

.footer-section ul li a:hover {
    opacity: 1;
    color: var(--accent-light);
    padding-left: 5px;
}

.footer-contact li {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 12px;
}

.footer-contact i {
    color: var(--accent-light);
    font-size: 0.95rem;
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-bottom p {
    font-size: 0.9rem;
    opacity: 0.7;
}

.footer-bottom a {
    color: var(--accent-light);
}

.footer-bottom a:hover {
    text-decoration: underline;
}

/* ===========================
   Scroll to Top Button
   =========================== */
.scroll-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--primary-color);
    color: var(--white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition-normal);
    z-index: 999;
}

.scroll-to-top.show {
    opacity: 1;
    visibility: visible;
}

.scroll-to-top:hover {
    background: var(--primary-dark);
    transform: translateY(-5px);
}

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

/* Tablet (768px - 1024px) */
@media (max-width: 1024px) {
    :root {
        --section-padding: 80px;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .hero-title {
        font-size: 2.75rem;
    }
    
    .about-content,
    .contact-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .about-stats {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .services-grid,
    .portfolio-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .field-categories-grid {
        grid-template-columns: 1fr;
    }
    
    .category-slider-container {
        height: 250px;
    }
    
    .equipment-grid {
        grid-template-columns: 1fr;
    }
    
    .cert-images-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .cert-images-grid.class-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .safety-features {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .qualifications-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-content {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* Mobile (max-width: 768px) */
@media (max-width: 768px) {
    :root {
        --section-padding: 60px;
    }
    
    /* Navigation */
    .mobile-menu-btn {
        display: block;
    }
    
    .logo-full {
        height: 50px;
        max-width: 250px;
    }
    
    .nav-menu {
        position: fixed;
        top: 85px;
        left: -100%;
        width: 100%;
        background: var(--white);
        flex-direction: column;
        padding: 30px 20px;
        box-shadow: var(--shadow-lg);
        gap: 20px;
        transition: var(--transition-normal);
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .nav-link::after {
        display: none;
    }
    
    /* Hero */
    .hero {
        min-height: 600px;
        background-attachment: scroll;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .hero-buttons .btn {
        width: 100%;
        max-width: 300px;
    }
    
    .hero-features {
        flex-direction: column;
        gap: 20px;
    }
    
    /* Sections */
    .section-title {
        font-size: 1.75rem;
    }
    
    .section-description {
        font-size: 1rem;
    }
    
    .about-stats {
        grid-template-columns: repeat(2, 1fr);
        gap: 20px;
    }
    
    .stat-number {
        font-size: 1.75rem;
    }
    
    .services-grid,
    .portfolio-grid {
        grid-template-columns: 1fr;
    }
    
    .field-categories-grid {
        grid-template-columns: 1fr;
    }
    
    .category-slider-container {
        height: 220px;
    }
    
    .category-header {
        padding: 20px;
    }
    
    .category-icon {
        width: 60px;
        height: 60px;
    }
    
    .category-icon i {
        font-size: 1.75rem;
    }
    
    .category-header h3 {
        font-size: 1.1rem;
    }
    
    .slider-btn {
        width: 35px;
        height: 35px;
    }
    
    .slider-btn i {
        font-size: 0.9rem;
    }
    
    .cert-images-grid,
    .cert-images-grid.class-grid {
        grid-template-columns: 1fr;
    }
    
    .safety-intro {
        padding: 30px 20px;
    }
    
    .safety-intro-content h3 {
        font-size: 1.5rem;
    }
    
    .safety-intro-content > p {
        font-size: 1rem;
    }
    
    .safety-features {
        grid-template-columns: 1fr;
        gap: 15px;
    }
    
    .safety-feature-item {
        padding: 20px;
    }
    
    .safety-feature-item i {
        font-size: 1.5rem;
        min-width: 30px;
    }
    
    .qualifications-grid {
        grid-template-columns: 1fr;
    }
    
    .cert-section {
        padding: 30px 20px;
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .contact-form-wrapper {
        padding: 30px 20px;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }
}

/* Small Mobile (max-width: 480px) */
@media (max-width: 480px) {
    .logo-full {
        height: 45px;
        max-width: 220px;
    }
    
    .hero-title {
        font-size: 1.75rem;
    }
    
    .about-stats {
        grid-template-columns: 1fr;
    }
    
    .cert-images-grid,
    .cert-images-grid.class-grid,
    .qualifications-grid {
        grid-template-columns: 1fr;
    }
    
    .btn {
        padding: 12px 24px;
        font-size: 0.95rem;
    }
}