:root {
    --primary-color: #8b5cf6;
    --primary-light: #ede9fe;
    --primary-medium: #a78bfa;
    --primary-dark: #7c3aed;
    --primary-darker: #6d28d9;
    --white: #ffffff;
    --gray-100: #f8f9fa;
    --gray-200: #e9ecef;
    --gray-300: #dee2e6;
    --gray-400: #ced4da;
    --gray-500: #adb5bd;
    --gray-600: #6c757d;
    --gray-700: #495057;
    --gray-800: #343a40;
    --gray-900: #212529;
}

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

body {
    font-family: 'Poppins', sans-serif;
    background: linear-gradient(135deg, var(--gray-400) 0%, var(--gray-500) 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    position: relative;
}

body::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image:
        radial-gradient(circle at 10% 20%, rgba(255, 255, 255, 0.1) 0%, transparent 20%),
        radial-gradient(circle at 90% 80%, rgba(207, 207, 207, 0.1) 0%, transparent 20%);
    z-index: -1;
}

.login-container {
    width: 100%;
    max-width: 440px;
}

.login-card {
    background: var(--white);
    border-radius: 16px;
    box-shadow: 0 10px 30px rgba(139, 92, 246, 0.15);
    overflow: hidden;
    transition: all 0.3s ease;
}

.card-header {
    background: var(--primary-color);
    padding: 30px 20px;
    text-align: center;
    color: var(--white);
    position: relative;
}

.brand-logo {
    display: inline-block;
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 5px;
    color: var(--white);
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.card-subtitle {
    font-size: 14px;
    opacity: 0.9;
    font-weight: 400;
    letter-spacing: 1px;
}

.card-body {
    padding: 22px 35px;
}

.form-group {
    margin-bottom: 24px;
    position: relative;
}

.form-label {
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--gray-700);
    font-size: 14px;
    display: block;
}

.input-wrapper {
    position: relative;
}

.form-control {
    border: 2px solid var(--gray-300);
    border-radius: 12px;
    padding: 14px 20px 14px 50px;
    font-size: 15px;
    font-weight: 500;
    transition: all 0.3s ease;
    background: var(--white);
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.05);
}

.form-control:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 4px rgba(139, 92, 246, 0.15);
    outline: none;
}

.form-control.is-invalid {
    border-color: #dc3545;
    background-image: none;
}

.input-icon {
    position: absolute;
    left: 18px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--gray-500);
    font-size: 18px;
    transition: all 0.3s ease;
}

.form-control:focus+.input-icon {
    color: var(--primary-color);
}

.invalid-feedback {
    font-size: 13px;
    margin-top: 8px;
    color: #dc3545;
    display: block;
    font-weight: 500;
}

.btn {
    padding: 15px 24px;
    font-weight: 600;
    border-radius: 12px;
    font-size: 16px;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    position: relative;
    overflow: hidden;
    margin-top: 15px;
}

.btn-primary {
    background: var(--primary-color);
    color: var(--white);
    width: 100%;
    box-shadow: 0 4px 15px rgba(139, 92, 246, 0.3);
}

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(139, 92, 246, 0.4);
}

.btn-primary:focus {
    box-shadow: 0 0 0 4px rgba(139, 92, 246, 0.2);
}

.alert {
    border-radius: 12px;
    padding: 15px 18px;
    margin-bottom: 25px;
    font-size: 14px;
    border: none;
    display: flex;
    align-items: center;
}

.alert-danger {
    background-color: #fae4e7;
    color: #dc3545;
    /* border: 2px dotted #dc3545; */
}

.alert i {
    font-size: 20px;
    margin-right: 12px;
}

/* Responsive Design */
@media (max-width: 768px) {
    .login-container {
        max-width: 100%;
    }

    .login-card {
        border-radius: 16px;
    }

    .card-header {
        padding: 25px 20px;
    }

    .card-body {
        padding: 30px 25px;
    }

    .form-control {
        padding: 12px 18px 12px 45px;
    }

    .input-icon {
        left: 16px;
    }
}

@media (max-width: 480px) {
    body {
        padding: 15px;
    }

    .card-header {
        padding: 20px 15px;
    }

    .card-body {
        padding: 25px 20px;
    }

    .brand-logo {
        font-size: 28px;
    }

    .btn {
        padding: 14px 20px;
        font-size: 15px;
    }
}