/* ===========================
   CSS Reset & Base Styles
   =========================== */

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

:root {
    /* Colors */
    --primary-color: #1a4d7a;
    --primary-dark: #0f3557;
    --accent-color: #F02c2c;
    --accent-hover: #d42424;
    --text-dark: #2c3e50;
    --text-light: #6c757d;
    --background: #ffffff;
    --background-light: #f8f9fa;
    --border-color: #e0e0e0;

    /* Typography */
    --font-primary: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --font-heading: 'Bree Serif', Georgia, serif;

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 3rem;
    --spacing-xl: 4rem;

    /* Other */
    --border-radius: 8px;
    --transition: all 0.3s ease;
    --shadow-sm: 0 2px 4px rgba(0,0,0,0.1);
    --shadow-md: 0 4px 8px rgba(0,0,0,0.12);
    --shadow-lg: 0 8px 16px rgba(0,0,0,0.15);
}

body {
    font-family: var(--font-primary);
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--background);
}

/* All headings using Songti TC should be bold */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-sm);
}

/* ===========================
   Header
   =========================== */

.header {
    background-color: var(--background);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 3px solid var(--accent-color);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) 0;
}

.logo {
    text-decoration: none;
    display: block;
    transition: var(--transition);
    line-height: 0;
}

.logo:hover {
    opacity: 0.8;
}

.logo img {
    height: 60px;
    width: auto;
    display: block;
}

.logo h1 {
    font-family: var(--font-heading);
    font-size: 1.8rem;
    color: var(--primary-color);
    margin-bottom: 0.2rem;
}

.logo .subtitle {
    font-size: 0.9rem;
    color: var(--text-light);
    font-weight: 400;
}

/* Desktop Navigation */
.nav-desktop {
    display: none;
}

.nav-desktop ul {
    display: flex;
    list-style: none;
    gap: var(--spacing-md);
}

.nav-desktop a {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    transition: var(--transition);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--border-radius);
}

.nav-desktop a:hover,
.nav-desktop a.active {
    color: var(--primary-color);
    background-color: var(--background-light);
}

/* Mobile Navigation */
.nav-mobile {
    display: none;
    background-color: var(--background);
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--shadow-md);
}

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

.nav-mobile ul {
    list-style: none;
    padding: var(--spacing-sm) 0;
}

.nav-mobile li {
    border-bottom: 1px solid var(--border-color);
}

.nav-mobile li:last-child {
    border-bottom: none;
}

.nav-mobile a {
    display: block;
    padding: var(--spacing-sm) var(--spacing-md);
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    transition: var(--transition);
}

.nav-mobile a:hover,
.nav-mobile a.active {
    background-color: var(--background-light);
    color: var(--primary-color);
}

/* Login Button */
.btn-login {
    display: none;
    padding: var(--spacing-xs) var(--spacing-md);
    background-color: var(--primary-color);
    color: white;
    text-decoration: none;
    border-radius: var(--border-radius);
    font-weight: 500;
    transition: var(--transition);
}

.btn-login:hover {
    background-color: var(--primary-dark);
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    width: 30px;
    height: 24px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0;
}

.mobile-menu-toggle span {
    display: block;
    width: 100%;
    height: 3px;
    background-color: var(--primary-color);
    transition: var(--transition);
    border-radius: 2px;
}

.mobile-menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(8px, 8px);
}

.mobile-menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.mobile-menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -7px);
}

/* ===========================
   Hero Section
   =========================== */

.hero {
    position: relative;
    height: 500px;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    background-image: url('../assets/images/hero-background.jpg');
    background-size: cover;
    background-position: center;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    text-align: center;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: url('../assets/images/hero-pattern.svg');
    background-size: cover;
    background-position: center;
    opacity: 0.1;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: transparent;
}

.hero-content {
    position: relative;
    z-index: 1;
    color: white;
    width: 100%;
    padding: 0 var(--spacing-md) var(--spacing-lg);
}

.hero-content h2 {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
}

.hero-tagline {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    margin: 0;
    color: white;
    text-shadow: 2px 2px 8px rgba(0,0,0,0.7);
}

.hero-description {
    font-size: 1.1rem;
    line-height: 1.8;
    opacity: 0.95;
}

/* ===========================
   Sections
   =========================== */

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

.section:nth-child(even) {
    background-color: var(--background-light);
}

.section-title {
    font-family: var(--font-heading);
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: var(--spacing-md);
    text-align: center;
}

.section-footer {
    text-align: center;
    margin-top: var(--spacing-lg);
}

/* Buttons */
.btn-secondary {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-md);
    background-color: var(--accent-color);
    color: white;
    text-decoration: none;
    border-radius: var(--border-radius);
    font-weight: 500;
    transition: var(--transition);
}

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

.read-more {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    transition: var(--transition);
}

.read-more:hover {
    color: var(--accent-color);
}

/* ===========================
   Footer
   =========================== */

.footer {
    background-color: var(--primary-dark);
    color: white;
    padding: var(--spacing-lg) 0 var(--spacing-md);
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.footer-section h3 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    margin-bottom: var(--spacing-sm);
    color: var(--accent-color);
}

.footer-section h4 {
    font-size: 1.1rem;
    margin-bottom: var(--spacing-sm);
    color: var(--accent-color);
}

.footer-section p {
    line-height: 1.8;
    opacity: 0.9;
}

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

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

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

.footer-links li {
    margin-bottom: var(--spacing-xs);
}

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

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

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

/* Mobile: smaller logo and hero text */
@media (max-width: 767px) {
    .logo img {
        height: 45px;
    }

    .hero {
        height: 400px;
    }

    .hero-tagline {
        font-size: 1.5rem;
    }

    .hero-content {
        padding: 0 var(--spacing-sm) var(--spacing-md);
    }
}

@media (min-width: 768px) {
    .mobile-menu-toggle {
        display: none;
    }

    .nav-desktop {
        display: block;
    }

    .btn-login {
        display: inline-block;
    }

    .hero {
        height: 600px;
        align-items: flex-end;
        padding-bottom: 100px;
    }

    .hero-content {
        padding: 0 var(--spacing-md) 0;
    }

    .hero-tagline {
        font-size: 3rem;
        font-weight: 700;
    }

    .hero-content h2 {
        font-size: 3.5rem;
    }

    .hero-description {
        font-size: 1.2rem;
    }

    .footer-content {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (min-width: 1024px) {
    .container {
        padding: 0 var(--spacing-md);
    }

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