/* Universal and Body Styles */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Inter', sans-serif;
}

body {
    min-height: 100vh;
    background: url('images/isu_campus_bg.jpg') center/cover no-repeat fixed;
    display: flex;
    flex-direction: column;
    position: relative;
    overflow-x: hidden;
}
body::before {
    content: "";
    position: fixed;
    inset: 0;
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(6px);
    z-index: -1;
}

/* Header (Top Bar) */
.top-bar {
    background: linear-gradient(to right, #06ab20, #1b75bc);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.6rem 1.5rem;
    flex-wrap: wrap;
    gap: 0.5rem;
}

/* Back to Homepage Button */
.back-btn {
    display: inline-flex;
    align-items: center;
    background: linear-gradient(to right, #06ab20, #1b75bc);
    color: white;
    text-decoration: none;
    font-weight: 500;
    font-size: 0.9rem;
    padding: 0.6rem 1rem;
    border-radius: 8px;
    border: 2px solid #06ab20;
    transition: background 0.3s ease, transform 0.2s ease;
}
.back-btn .material-icons {
    font-size: 1.2rem;
    margin-right: 6px;
}
.back-btn:hover {
    background: linear-gradient(to right, #04961c, #155a99);
    transform: scale(1.05);
}

/* Brand Title */
.brand {
    text-align: center;
    flex: 1 1 auto;
}
.brand h1 {
    font-size: 1.4rem;
    font-weight: 600;
    line-height: 1;
}
.brand span {
    font-size: 0.8rem;
}

/* Logos */
.logos {
    display: flex;
    gap: 0.8rem;
}
.logo {
    width: 60px;
    height: 60px;
    object-fit: cover;
    background: #06ab20;
    border-radius: 50%;
    border: 2px solid #06ab20;
}

/* Centered Page Container */
.centered-page {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem;
}

/* Login Card Styles */
.login-card {
    width: 100%;
    max-width: 420px;
    background: #ffffff;
    padding: 2.5rem;
    border-radius: 1rem;
    box-shadow: 0 10px 50px rgba(0, 0, 0, 0.4);
}
.login-card h1 {
    text-align: center;
    margin-bottom: 2rem;
    font-size: 2rem;
    font-weight: 700;
    color: #1b1b1b;
}

/* Form Styling */
form {
    display: flex;
    flex-direction: column;
}

/* Floating Labels */
.form-group {
    position: relative;
    margin-bottom: 2rem;
}
.form-group input {
    width: 100%;
    padding: 1rem .8rem;
    font-size: 1rem;
    border: 1px solid #ccc;
    border-radius: 8px;
    background: none;
    transition: border-color 0.3s, box-shadow 0.3s;
}
.form-group input::placeholder {
    opacity: 0;
    transition: opacity 0.2s ease-in-out;
}
.form-group label {
    position: absolute;
    top: 1rem;
    left: 1rem;
    color: #888;
    font-size: 1rem;
    pointer-events: none;
    background: white;
    padding: 0 0.3rem;
    transition: all 0.3s ease;
}
.form-group input:focus,
.form-group input:not(:placeholder-shown) {
    border-color: #60a807;
}
.form-group input:focus::placeholder,
.form-group input:not(:placeholder-shown)::placeholder {
    opacity: 1;
}
.form-group input:focus + label,
.form-group input:not(:placeholder-shown) + label {
    top: -0.6rem;
    left: 0.8rem;
    font-size: 0.75rem;
    color: #60a807;
}

/* Button */
button {
    background-color: #60a807;
    border: none;
    border-radius: 8px;
    padding: 0.9rem;
    color: #fff;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.25s ease;
}
button:hover {
    opacity: 0.95;
    transform: scale(1.03);
}

/* Signup Link */
.signup {
    margin-top: 1rem;
    text-align: center;
    font-size: 0.9rem;
}
.signup a {
    color: #1b75bc;
    text-decoration: none;
}
.signup a:hover {
    text-decoration: underline;
}

/* Mobile Styles */
@media (max-width: 480px) {
    .top-bar {
        padding: 0.3rem 1rem;
        flex-direction: row;
        justify-content: space-between;
        gap: 0.5rem;
    }

    .back-btn {
        padding: 0.4rem 0.6rem;
        font-size: 0;
        border-radius: 50%;
        width: 40px;
        height: 40px;
        justify-content: center;
    }

    .back-btn .material-icons {
        font-size: 1.4rem;
        margin: 0;
    }

    .brand h1 {
        font-size: 1rem;
    }

    .brand span {
        font-size: 0.65rem;
    }

    .logos {
        display: none;
    }

    .login-card {
        padding: 1.5rem;
        border-radius: 0.75rem;
    }

    .centered-page {
        padding: 1rem;
    }
}