/* -----------------------------------
   Reset & base
----------------------------------- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: #f0f2f5; /* subtle light background */
    color: #1a202c; /* dark gray text */
    line-height: 1.6;
    min-height: 100vh;
}

/* -----------------------------------
   Header & Navigation
----------------------------------- */
header {
    background: linear-gradient(135deg, #4a90e2, #2d3748);
    color: white;
    padding-right: 2em;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    box-shadow: 0 3px 10px rgba(0,0,0,0.15);
}

header h1 {
    font-size: 1.8rem;
    letter-spacing: 1px;
}

nav a {
    color: white;
    margin-left: 1.5em;
    text-decoration: none;
    font-weight: 500;
    position: relative;
}

nav a::after {
    content: '';
    display: block;
    height: 2px;
    width: 0;
    background: #ffce00;
    transition: width 0.3s;
    position: absolute;
    bottom: -4px;
    left: 0;
}

nav a:hover::after {
    width: 100%;
}

/* -----------------------------------
   Main content container
----------------------------------- */
main {
    max-width: 900px;
    margin: 2.5em auto;
    padding: 2em;
    background: rgba(255,255,255,0.95);
    border-radius: 12px;
    box-shadow: 0 8px 25px rgba(0,0,0,0.1);
    position: relative;
    min-height: 60vh;
}

/* Placeholder for background image */
main::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background: url('./assets/bg.png') no-repeat center center;
    background-size: cover;
    opacity: 0.05;
    border-radius: 12px;
    pointer-events: none;
    z-index: 0;
}

main > * {
    position: relative;
    z-index: 1;
}

/* -----------------------------------
   Buttons
----------------------------------- */
button {
    background: #4a90e2;
    color: white;
    border: none;
    padding: 0.7em 1.5em;
    border-radius: 6px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 600;
}

button:hover {
    background: #357ab8;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

/* -----------------------------------
   Forms
----------------------------------- */
form input[type="file"] {
    padding: 0.5em;
    border-radius: 6px;
    border: 1px solid #ccc;
    cursor: pointer;
}

form input[type="file"]:hover {
    border-color: #4a90e2;
}

/* -----------------------------------
   Calendar & cards
----------------------------------- */
#calendar div {
    background: #e2e8f0;
    padding: 1em;
    margin: 0.5em 0;
    border-radius: 8px;
    transition: all 0.3s;
}

#calendar div:hover {
    background: #4a90e2;
    color: white;
    transform: scale(1.02);
    cursor: pointer;
}

/* Card for TSS detail */
#details {
    display: flex;
    flex-direction: column;
    gap: 1em;
    background: #edf2f7;
    padding: 1.5em;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
}

#details p {
    font-size: 1.05rem;
}

/* -----------------------------------
   Footer
----------------------------------- */
footer {
    background: #2d3748;
    color: white;
    text-align: center;
    padding: 1em;
    margin-top: 3em;
}

/* -----------------------------------
   Responsive
----------------------------------- */
@media(max-width: 600px) {
    header {
        flex-direction: column;
        text-align: center;
    }

    nav a {
        margin: 0.5em 0;
    }
}

header .logo img {
    height: 100px; /* adjust logo size */
    width: auto;
    display: block;
}