:root {
    --bg-dark: #0b0f19;
    --card-bg: rgba(18, 24, 38, 0.85);
    --border-color: rgba(255, 255, 255, 0.08);
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --text-main: #f3f4f6;
    --text-muted: #9ca3af;
    --error: #ef4444;
    --error-bg: rgba(239, 68, 68, 0.12);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: radial-gradient(circle at 50% 20%, #172554 0%, #0b0f19 80%);
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1.5rem;
}

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

.login-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 1.25rem;
    padding: 2.5rem 2rem;
    backdrop-filter: blur(16px);
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5), 0 0 30px rgba(59, 130, 246, 0.15);
}

.brand-header {
    text-align: center;
    margin-bottom: 2rem;
}

.logo-badge {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    filter: drop-shadow(0 4px 12px rgba(59, 130, 246, 0.3));
}

.brand-header h1 {
    font-size: 1.875rem;
    font-weight: 700;
    letter-spacing: -0.025em;
    background: linear-gradient(135deg, #ffffff 0%, #93c5fd 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.brand-header .subtitle {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-top: 0.35rem;
}

.form-group {
    margin-bottom: 1.25rem;
}

label {
    display: block;
    font-size: 0.8125rem;
    font-weight: 500;
    color: var(--text-main);
    margin-bottom: 0.4rem;
}

input {
    width: 100%;
    background: rgba(15, 23, 42, 0.6);
    border: 1px solid var(--border-color);
    border-radius: 0.625rem;
    padding: 0.75rem 1rem;
    color: #fff;
    font-size: 0.9375rem;
    transition: all 0.2s ease;
}

input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.25);
    background: rgba(15, 23, 42, 0.85);
}

.input-hint {
    display: block;
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 0.35rem;
}

.btn-primary {
    width: 100%;
    background: linear-gradient(135deg, #3b82f6 0%, #1d4ed8 100%);
    color: white;
    border: none;
    border-radius: 0.625rem;
    padding: 0.85rem;
    font-size: 0.9375rem;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.15s ease, box-shadow 0.15s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    margin-top: 1.5rem;
}

.btn-primary:hover {
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.4);
    transform: translateY(-1px);
}

.btn-primary:active {
    transform: translateY(0);
}

.alert-error {
    background: var(--error-bg);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: #fca5a5;
    padding: 0.75rem 1rem;
    border-radius: 0.625rem;
    font-size: 0.8125rem;
    margin-bottom: 1.25rem;
    animation: fadeIn 0.2s ease;
}

.login-footer {
    margin-top: 1.75rem;
    text-align: center;
    border-top: 1px solid var(--border-color);
    padding-top: 1.25rem;
}

.back-link {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.8125rem;
    transition: color 0.2s ease;
}

.back-link:hover {
    color: #fff;
}

.quick-credentials {
    margin-top: 0.75rem;
}

.quick-credentials code {
    background: rgba(255, 255, 255, 0.08);
    padding: 0.15rem 0.35rem;
    border-radius: 4px;
    font-size: 0.75rem;
    color: #93c5fd;
}

.spinner {
    width: 18px;
    height: 18px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 0.6s linear infinite;
}

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

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-4px); }
    to { opacity: 1; transform: translateY(0); }
}