/* Base CSS - Mobile-first approach */
:root {
    --primary-color: #3498db;
    --primary-dark: #2980b9;
    --success-color: #27ae60;
    --error-color: #e74c3c;
    --warning-color: #f39c12;
    --text-color: #2c3e50;
    --text-light: #7f8c8d;
    --bg-color: #ecf0f1;
    --white: #ffffff;
    --border-color: #bdc3c7;
    --shadow: 0 2px 10px rgba(0,0,0,0.1);
    --border-radius: 8px;
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    font-size: 16px;
}

.container {
    max-width: 400px;
    margin: 0 auto;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.app-header {
    text-align: center;
    margin-bottom: 40px;
    padding: 20px 0;
}

.app-header h1 {
    color: var(--primary-color);
    font-size: 24px;
    margin-bottom: 8px;
}

.app-header p {
    color: var(--text-light);
    font-size: 14px;
}

/* Form styles */
.input-group {
    margin-bottom: 20px;
}

.input-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: var(--text-color);
}

.input-group input {
    width: 100%;
    padding: 15px;
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 16px;
    transition: var(--transition);
    background-color: var(--white);
}

.input-group input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.1);
}

/* Button styles */
.btn-primary {
    width: 100%;
    padding: 15px;
    background-color: var(--primary-color);
    color: var(--white);
    border: none;
    border-radius: var(--border-radius);
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    margin-top: 20px;
}

.btn-primary:hover {
    background-color: var(--primary-dark);
}

.btn-primary:disabled {
    background-color: var(--text-light);
    cursor: not-allowed;
}

/* Utility classes */
.hidden {
    display: none !important;
}

.error-message {
    background-color: var(--error-color);
    color: var(--white);
    padding: 12px;
    border-radius: var(--border-radius);
    margin-top: 15px;
    text-align: center;
}

.success-message {
    background-color: var(--success-color);
    color: var(--white);
    padding: 12px;
    border-radius: var(--border-radius);
    margin-top: 15px;
    text-align: center;
}

.test-credentials {
    margin-top: 40px;
    padding: 20px;
    background-color: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    text-align: center;
}

.test-credentials h3 {
    color: var(--primary-color);
    margin-bottom: 15px;
}

.test-credentials p {
    margin-bottom: 8px;
}

.loader {
    opacity: 0.7;
}