body {
    background: #f5f5f5;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.login-container {
    background: #ffffff;
    border: 1px solid #e0e0e0;
    padding: 0;
    max-width: 380px;
    width: 100%;
    margin: 20px;
}

.login-box {
    padding: 30px 30px;
    max-width: 100%;
    margin: 0;
}

.login-header {
    text-align: center;
    margin-bottom: 25px;
}

.login-header i {
    font-size: 1.5rem;
    color: #333;
    margin-bottom: 8px;
}

.login-header h1 {
    color: #333;
    font-weight: 400;
    margin-bottom: 5px;
    font-size: 1.4rem;
}

.form-group { margin-bottom: 18px; }

.form-label {
    font-weight: 400;
    color: #333;
    margin-bottom: 5px;
    font-size: 14px;
}

.form-control {
    border: 1px solid #ddd;
    border-radius: 0;
    padding: 10px 12px;
    font-size: 14px;
    transition: border-color 0.2s ease;
    background: #fff;
}

.form-control:focus {
    border-color: #333;
    box-shadow: none;
    outline: none;
}

.btn-primary {
    background: #333;
    border: 1px solid #333;
    border-radius: 0;
    padding: 12px 20px;
    font-weight: 400;
    font-size: 14px;
    width: 100%;
    transition: background-color 0.2s ease;
}

.btn-primary:hover {
    background: #555;
    border-color: #555;
    transform: none;
    box-shadow: none;
}

.captcha-box { margin-bottom: 18px; }

.captcha-container {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 8px;
}

#captcha-canvas {
    border: 1px solid #ddd;
    border-radius: 0;
    background: #fff;
    width: 100%;
    max-width: calc(100% - 50px);
}

.refresh-btn {
    background: #fff;
    color: #333;
    border: 1px solid #ddd;
    border-radius: 0;
    padding: 8px;
    cursor: pointer;
    transition: background-color 0.2s ease;
}

.refresh-btn:hover {
    background: #f5f5f5;
    transform: none;
}

.alert {
    border-radius: 0;
    border: 1px solid;
    margin-bottom: 18px;
    padding: 10px 12px;
    font-size: 14px;
}

.alert-danger {
    background: #fff;
    color: #d32f2f;
    border-color: #d32f2f;
}

.alert-warning {
    background: #fff;
    color: #f57c00;
    border-color: #f57c00;
}

.alert-success {
    background: #fff;
    color: #388e3c;
    border-color: #388e3c;
}

.input-group .btn-outline-secondary {
    border-color: #ddd;
    color: #333;
    border-radius: 0;
    background: #fff;
}

.input-group .btn-outline-secondary:hover {
    background-color: #f5f5f5;
    border-color: #ddd;
    color: #333;
}

.text-muted { color: #666 !important; }

a { color: #333; text-decoration: underline; }

a:hover { color: #555; }

.link-accent {
    color: #667eea;
    text-decoration: none;
    font-weight: 600;
}

.link-accent:hover {
    color: #556cd6;
    text-decoration: underline;
}

@media (max-width: 768px) {
    .login-box { padding: 25px 20px; }
    .login-header i { font-size: 1.3rem; }
}