:root {
    --bg-primary: #ffffff;
    --bg-button: rgb(34,146,221);
    --bg-nav: linear-gradient(135deg, rgb(0, 101, 168), rgb(51, 74, 88));
    --bg-card: #ffffff;
    --bg-header: linear-gradient(135deg, #dbeafe, #f0f9ff);
    
    --text-primary: #000000;
    --text-button: rgb(255, 255, 255);
    --text-nav: #dce2eb;
    --text-nav-hover: #2563eb;
    --text-logo-h1: #dbe0ec;
    --text-logo-p: #dfe7f3;
    --text-title: #000000;
    --text-details: #333333;
    --text-heading: #1e40af;
    --text-subheading: #475569;
    
    --border-button: rgb(34,146,221);
    --nav-shadow: rgba(0,0,0,0.08);
    --text-shadow: gray;
}

body:has(#theme-toggle:checked) {
    --bg-primary: #0f172a;
    --bg-button: #60a5fa;
    --bg-nav: linear-gradient(135deg, #1e3a5f, #2d3748);
    --bg-card: #1e293b;
    --bg-header: linear-gradient(135deg, #1e3a5f, #2d4a6e);
    
    --text-primary: #e2e8f0;
    --text-button: #ffffff;
    --text-nav: #e2e8f0;
    --text-nav-hover: #60a5fa;
    --text-logo-h1: #dbe0ec;
    --text-logo-p: #dfe7f3;
    --text-title: #e2e8f0;
    --text-details: #cbd5e1;
    --text-heading: #93c5fd;
    --text-subheading: #cbd5e1;
    
    --border-button: #60a5fa;
    --nav-shadow: rgba(0,0,0,0.3);
    --text-shadow: #334155;
}

.theme-checkbox {
    display: none;
}

*{
    font-family: "Poppins",sans-serif;
}

body {
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: background-color 0.3s ease, color 0.3s ease;
}

button{
    border-radius: 25px;
    background-color: var(--bg-button);
    border-color: var(--border-button);
    width: 105px;
    height: 30px;
    color: var(--text-button);
    float: left;
    margin-left: 350%;
    transition: background-color 0.3s ease, border-color 0.3s ease;
}

.nav{
    background: var(--bg-nav);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 50px;
    box-shadow: 0 3px 10px var(--nav-shadow);
    position: sticky;
    top: 0;
    z-index: 10;
    margin-top: -1%;
    margin-left: -3%;
    margin-right: -0.6%;
    transition: background 0.3s ease, box-shadow 0.3s ease;
}

.logo-area{
    display:flex;
    align-items:center;
    gap: 10px;
}

.logo-circle{ 
    background: var(--bg-nav);
    color:white;
    font-size:1.6rem;
    border-radius:50%;
    width:55px;
    height:55px;
    display:flex;
    justify-content:center;
    align-items:center;
    transition:transform 0.3s;
}

.logo-circle:hover{
    transform:rotate(10deg) scale(1.1);
}

.logo-text h1{
    margin:0;
    font-size:1.4rem;
    color:var(--text-logo-h1);
}

.logo-text p{
    margin:0;
    font-size:0.85rem;
    color:var(--text-logo-p);
}

.menu {
    display: flex;
    align-items: center;
    gap: 10px;
}

.menu a{
    text-decoration:none;
    color:var(--text-nav);
    margin:0 10px;
    font-weight:500;
    padding:6px 10px;
    border-radius:6px;
    transition:0.3s;
}   

.menu a:hover {
  background-color: rgb(255, 255, 255);
  color: white,var(--text-nav-hover);
}


.menu .active{
    color: #cbd4e7;
    font-weight: 600;
}

.theme-switch {
    cursor: pointer;
    width: 50px;
    height: 26px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 30px;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-left: 10px;
    transition: background 0.3s ease;
    border: 2px solid rgba(255, 255, 255, 0.3);
}

.theme-icon {
    display: none;
}

.theme-switch::after {
    content: "";
    position: absolute;
    width: 20px;
    height: 20px;
    background: white;
    border-radius: 50%;
    left: 3px;
    transition: transform 0.3s ease;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

body:has(#theme-toggle:checked) .theme-switch::after {
    transform: translateX(24px);
}

.page-header {
    background: var(--bg-header);
    text-align: center;
    padding: 60px 20px;
    margin: -8px -8px 40px -8px;
    border-radius: 0 0 30px 30px;
    transition: background 0.3s ease;
}

.main-heading {
    font-size: 3rem;
    font-weight: 700;
    color: var(--text-heading);
    margin: 0 0 15px 0;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.1);
    transition: color 0.3s ease;
    font-family: 'Times New Roman', Times, serif;
}

.sub-heading {
    font-size: 1.2rem;
    color: var(--text-subheading);
    margin: 0;
    font-weight: 400;
    transition: color 0.3s ease;
}

.event-card {
    width: 350px;
    border-radius: 15px;
    overflow: hidden;
    text-align: center;
    transition: all 0.3s ease;
    padding: 20px;
    background-color: var(--bg-card);
}

.event-title {
    padding-right: 50px;
    margin: 10px 0;
    font-size: 20px;
    font-weight: bold;
    cursor: pointer;
    transition: color 0.3s ease;
    font-family:'Times New Roman', Times, serif;
    font-style: oblique;
    text-decoration: underline;
    text-shadow: 2px 2px 5px var(--text-shadow);
    color: var(--text-title);
}

.event-details {
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    transition: all 0.5s ease;
    margin-right: 80px;
    color: var(--text-details);
}

.event-card:hover .event-details {
    max-height: 300px;
    opacity: 1;
}