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

:root {
    --primary-color: #6c8eef;
    --primary-hover: #5a7ad9;
    --secondary-color: #f8f9fc;
    --text-primary: #2c3e50;
    --text-secondary: #7f8c8d;
    --border-color: #e9ecef;
    --success-color: #4ade80;
    --warning-color: #fbbf24;
    --danger-color: #f87171;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.04), 0 1px 3px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.03), 0 5px 10px rgba(0, 0, 0, 0.05);
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #f5f7fa 0%, #e4ecfb 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    color: var(--text-primary);
    line-height: 1.5;
}

.login-container {
    background: white;
    padding: 2.5rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    width: 100%;
    max-width: 420px;
    animation: fadeInUp 0.5s ease;
    border: 1px solid var(--border-color);
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

h2 {
    text-align: center;
    color: var(--text-primary);
    margin-bottom: 2rem;
    font-size: 1.75rem;
    font-weight: 600;
    letter-spacing: -0.01em;
}

.form-group {
    margin-bottom: 1.5rem;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
    font-weight: 500;
    font-size: 0.875rem;
}

input[type="text"],
input[type="password"] {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    transition: all 0.2s ease;
    background-color: white;
}

input[type="text"]:focus,
input[type="password"]:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(108, 142, 239, 0.1);
}

input[type="text"]:invalid,
input[type="password"]:invalid {
    border-color: var(--danger-color);
}

button {
    width: 100%;
    padding: 0.875rem;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
    margin-top: 1rem;
}

button:hover {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

button:active {
    transform: translateY(0);
}

.test-users {
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border-color);
    text-align: center;
}

.test-users h3 {
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 1rem;
}

.test-users p {
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.test-users strong {
    color: var(--text-primary);
    font-weight: 500;
    background-color: var(--secondary-color);
    padding: 0.25rem 0.5rem;
    border-radius: var(--radius-sm);
    font-family: 'SF Mono', 'Courier New', monospace;
    font-size: 0.875rem;
}

.error-message {
    background-color: rgba(248, 113, 113, 0.1);
    color: var(--danger-color);
    padding: 0.75rem 1rem;
    border-radius: var(--radius-md);
    margin-bottom: 1rem;
    font-size: 0.875rem;
    border: 1px solid rgba(248, 113, 113, 0.2);
    animation: shake 0.5s ease;
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    10%, 30%, 50%, 70%, 90% { transform: translateX(-5px); }
    20%, 40%, 60%, 80% { transform: translateX(5px); }
}

/* Loading state */
button:disabled {
    opacity: 0.7;
    cursor: not-allowed;
}

.loading {
    display: inline-block;
    width: 16px;
    height: 16px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
    margin-left: 0.5rem;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Responsive */
@media (max-width: 480px) {
    .login-container {
        padding: 2rem 1.5rem;
    }
    
    h2 {
        font-size: 1.5rem;
    }
}

/* Focus visible for accessibility */
button:focus-visible,
input:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* Password visibility toggle */
.password-wrapper {
    position: relative;
}

.password-toggle {
    position: absolute;
    right: 1rem;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 0.25rem;
    width: auto;
    margin: 0;
}

.password-toggle:hover {
    color: var(--text-primary);
}

/* Стили для валидации */
input.error {
    border-color: var(--danger-color) !important;
    background-color: rgba(248, 113, 113, 0.05) !important;
    box-shadow: 0 0 0 3px rgba(248, 113, 113, 0.1) !important;
}

input.error:focus {
    border-color: var(--danger-color) !important;
    box-shadow: 0 0 0 3px rgba(248, 113, 113, 0.2) !important;
}