:root {
    --primary-color: #004a99; /* น้ำเงินเข้มที่สดใสขึ้น */
    --secondary-color: #ff2d78; /* ชมพูที่มีความสดใหม่ */
    --accent-color: #00d2ff;
    --text-dark: #1a1a1a;
    --text-light: #666666;
    --bg-light: #f8fbff;
    --white: #ffffff;
    --shadow: 0 10px 30px rgba(0,0,0,0.08);
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

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

body {
    font-family: 'Sarabun', 'Kanit', sans-serif;
    line-height: 1.7;
    color: var(--text-dark);
    background-color: var(--white);
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 25px;
}

/* Header & Navigation */
header {
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow);
    padding: 10px 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    transition: var(--transition);
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    text-decoration: none;
}

.logo img {
    height: 75px;
    width: auto;
    margin-right: 15px;
    transition: var(--transition);
}

.logo-text h1 {
    font-size: 1.4rem;
    color: var(--primary-color);
    font-weight: 700;
    line-height: 1.2;
}

.logo-text p {
    font-size: 0.85rem;
    color: var(--text-light);
    font-family: 'Kanit', sans-serif;
    letter-spacing: 0.5px;
}

nav ul {
    display: flex;
    list-style: none;
    align-items: center;
}

nav ul li {
    margin-left: 25px;
}

nav ul li a {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    font-size: 1.05rem;
    transition: var(--transition);
    position: relative;
}

nav ul li a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--secondary-color);
    transition: var(--transition);
}

nav ul li a:hover::after, nav ul li a.active::after {
    width: 100%;
}

nav ul li a:hover, nav ul li a.active {
    color: var(--secondary-color);
}

.btn-admission {
    background: linear-gradient(45deg, var(--secondary-color), #ff6b9d);
    color: var(--white) !important;
    padding: 10px 25px;
    border-radius: 50px;
    font-weight: 700 !important;
    box-shadow: 0 4px 15px rgba(255, 45, 120, 0.3);
}

.btn-admission:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(255, 45, 120, 0.4);
    background: var(--primary-color) !important;
}

/* Hero Section */
.hero {
    height: 90vh;
    background: linear-gradient(rgba(0, 40, 80, 0.6), rgba(0, 40, 80, 0.8)), url('../images/hero-bg.jpg');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    display: flex;
    align-items: center;
    color: var(--white);
    text-align: left;
}

.hero-content {
    max-width: 800px;
    animation: fadeInUp 1s ease-out;
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

.hero-content h2 {
    font-size: 4rem;
    margin-bottom: 20px;
    font-family: 'Kanit', sans-serif;
    line-height: 1.1;
    text-shadow: 2px 2px 10px rgba(0,0,0,0.3);
}

.hero-content p {
    font-size: 1.5rem;
    margin-bottom: 40px;
    opacity: 0.9;
    font-weight: 300;
}

.hero-btns a {
    text-decoration: none;
    padding: 15px 40px;
    border-radius: 50px;
    font-weight: 700;
    margin-right: 20px;
    display: inline-block;
    transition: var(--transition);
}

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

.btn-secondary {
    border: 2px solid var(--white);
    color: var(--white);
    backdrop-filter: blur(5px);
}

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

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

/* Sections General */
section {
    padding: 100px 0;
}

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

.section-title span {
    color: var(--secondary-color);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 3px;
    font-size: 0.9rem;
    display: block;
    margin-bottom: 10px;
}

.section-title h3 {
    font-size: 2.8rem;
    color: var(--primary-color);
    font-family: 'Kanit', sans-serif;
}

/* Cards & Hover Effects */
.card {
    background: var(--white);
    border-radius: 20px;
    padding: 40px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid rgba(0,0,0,0.03);
}

.card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0,0,0,0.12);
}

/* Page Headers */
.page-header {
    background: linear-gradient(135deg, var(--primary-color), #002a55);
    color: var(--white);
    padding: 80px 0;
    text-align: center;
}

.page-header h2 {
    font-size: 3.5rem;
    font-family: 'Kanit', sans-serif;
    margin-bottom: 15px;
}

/* Footer */
footer {
    background-color: #001a33;
    color: var(--white);
    padding: 80px 0 30px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 60px;
    margin-bottom: 60px;
}

.footer-about h4, .footer-links h4, .footer-contact h4 {
    font-size: 1.3rem;
    margin-bottom: 25px;
    position: relative;
    padding-bottom: 10px;
}

.footer-about h4::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 50px;
    height: 3px;
    background-color: var(--secondary-color);
}

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

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

.footer-links ul li a {
    color: rgba(255,255,255,0.7);
    text-decoration: none;
    transition: var(--transition);
}

.footer-links ul li a:hover {
    color: var(--secondary-color);
    padding-left: 8px;
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255,255,255,0.1);
    font-size: 0.95rem;
    color: rgba(255,255,255,0.5);
}

/* Slider Section */
.slideshow-container {
    max-width: 1000px;
    position: relative;
    margin: auto;
    border-radius: 20px;
    overflow: hidden;
    box-shadow: var(--shadow);
}

.mySlides {
    display: none;
}

.mySlides img {
    width: 100%;
    height: 500px;
    object-fit: cover;
}

.fade {
    animation-name: fade;
    animation-duration: 1.5s;
}

@keyframes fade {
    from {opacity: .4} 
    to {opacity: 1}
}

.dots-container {
    text-align: center;
    padding: 20px;
}

.dot {
    height: 12px;
    width: 12px;
    margin: 0 5px;
    background-color: #bbb;
    border-radius: 50%;
    display: inline-block;
    transition: background-color 0.6s ease;
}

.active-dot {
    background-color: var(--secondary-color);
}

/* Responsive */
@media (max-width: 992px) {
    .mySlides img { height: 350px; }
    .hero-content h2 { font-size: 3rem; }
    .footer-grid { grid-template-columns: 1fr; gap: 40px; }
}

@media (max-width: 768px) {
    header .container { flex-direction: column; text-align: center; }
    nav ul { margin-top: 25px; flex-wrap: wrap; justify-content: center; }
    nav ul li { margin: 10px; }
    .hero-content { text-align: center; }
    .hero-btns a { margin: 10px; }
    .page-header h2 { font-size: 2.5rem; }
}