/* ========================================
   CSS VARIABLES
   ======================================== */
:root {
    --primary-color: #2c3e50;
    --secondary-color: #34495e;
    --accent-color: #ecf0f1;
    --text-light: #ffffff;
    --text-muted: #bdc3c7;
    --transition: 0.3s ease;
    --navbar-height: 70px;
    --shadow-light: 0 2px 4px rgba(0,0,0,0.1);
    --shadow-medium: 0 2px 8px rgba(0,0,0,0.2);
}

/* ========================================
   BASE LAYOUT & RESET
   ======================================== */
html {
    min-height: 100%;
}

body {
    margin: 0;
    font-family: Arial, sans-serif;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.container {
    display: flex;
    flex-direction: column;
    flex: 1;
}

/* ========================================
   NAVIGATION BAR
   ======================================== */
.navbar {
    background-color: var(--primary-color);
    width: 100%;
    padding: 0 20px;
    box-sizing: border-box;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: var(--shadow-light);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-brand h2 {
    color: var(--text-light);
    margin: 0;
    padding: 15px 0;
}

/* ========================================
   NAVIGATION MENU
   ======================================== */
.nav-menu {
    list-style-type: none;
    padding: 0;
    margin: 0;
    display: flex;
    align-items: center;
}

.nav-menu li {
    position: relative;
}

.nav-menu li a,
.dropdown-toggle {
    text-decoration: none;
    color: var(--text-muted);
    display: block;
    padding: 20px 15px;
    transition: color var(--transition);
    cursor: pointer;
}

/* ========================================
   DROPDOWN — CSS-only :hover
   ======================================== */
.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    background-color: var(--secondary-color);
    min-width: 200px;
    box-shadow: var(--shadow-medium);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all var(--transition);
    list-style-type: none;
    padding: 0;
    margin: 0;
    border-radius: 4px;
}

.dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-menu li a {
    padding: 12px 20px;
    border-bottom: 1px solid var(--primary-color);
}

.dropdown-menu li:last-child a {
    border-bottom: none;
}

/* ========================================
   MAIN CONTENT AREA
   ======================================== */
.main-content {
    flex: 1;
    padding: 20px;
    background-color: var(--accent-color);
    min-height: calc(100vh - 80px);
    max-width: 1200px;
    margin: 0 auto;
    box-sizing: border-box;
}

/* ========================================
   MOBILE MENU TOGGLE — checkbox hack
   ======================================== */
.menu-toggle-checkbox {
    display: none;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
    padding: 10px;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background-color: var(--text-light);
    margin: 3px 0;
    transition: var(--transition);
}

/* Hamburger → X animation */
#menu-toggle:checked ~ .mobile-menu-toggle span:nth-child(1) {
    transform: rotate(-45deg) translate(-5px, 6px);
}

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

#menu-toggle:checked ~ .mobile-menu-toggle span:nth-child(3) {
    transform: rotate(45deg) translate(-5px, -6px);
}

/* ========================================
   MOBILE RESPONSIVE
   ======================================== */
@media screen and (max-width: 768px) {
    .navbar {
        padding: 0 15px;
    }

    .nav-menu {
        position: fixed;
        top: -100vh;
        left: 0;
        width: 100%;
        height: calc(100vh - var(--navbar-height));
        background-color: var(--primary-color);
        flex-direction: column;
        align-items: flex-start;
        transition: top var(--transition);
        overflow-y: auto;
    }

    /* Show menu when checkbox is checked */
    #menu-toggle:checked ~ .nav-menu {
        top: var(--navbar-height);
    }

    .nav-menu li {
        width: 100%;
        border-bottom: 1px solid var(--secondary-color);
    }

    .nav-menu li a,
    .dropdown-toggle {
        padding: 15px 20px;
        width: 100%;
        box-sizing: border-box;
    }

    /* Dropdown items always visible on mobile */
    .dropdown-menu {
        position: static;
        background-color: var(--secondary-color);
        box-shadow: none;
        width: 100%;
        opacity: 1;
        visibility: visible;
        transform: none;
        display: block;
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .nav-brand h2 {
        font-size: 1.2em;
    }
}

/* ========================================
   TABLE STYLING
   ======================================== */
.main-content table td {
    vertical-align: top;
    padding: 1.5rem;
}

.main-content table img {
    display: block;
    margin: 0;
}

.main-content table td p:first-child,
.main-content table td ul:first-child {
    margin-top: 0;
}