:root {
    /* Default Dark Theme Variables */
    --bg-body: #0f172a;
    /* Slate 900 */
    --bg-surface: #1e293b;
    /* Slate 800 */
    --text-primary: #f8fafc;
    /* Slate 50 */
    --text-secondary: #94a3b8;
    /* Slate 400 */
    --input-bg: #334155;
    /* Slate 700 */
    --input-border: #475569;
    /* Slate 600 */
    --glass-bg: rgba(15, 23, 42, 0.75);
    /* Slate 900 transparent */
    --glass-border: rgba(255, 255, 255, 0.1);
    --primary-color: #3B82F6;
    --primary-hover: #2563EB;
    --accent-glow: rgba(59, 130, 246, 0.08);
}

[data-theme="light"] {
    --bg-body: #f8fafc;
    --bg-surface: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --input-bg: #ffffff;
    --input-border: #cbd5e1;
    --glass-bg: rgba(255, 255, 255, 0.85);
    --glass-border: rgba(255, 255, 255, 0.4);
    --accent-glow: rgba(59, 130, 246, 0.05);
}

body {
    background-color: var(--bg-body);
    color: var(--text-primary);
    background-image: radial-gradient(circle at 15% 50%, var(--accent-glow), transparent 25%),
        radial-gradient(circle at 85% 30%, var(--accent-glow), transparent 25%);
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.login-card {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.1);
    width: 100%;
    max-width: 420px;
    padding: 2.5rem;
    position: relative;
    overflow: hidden;
    transition: background 0.3s ease, border-color 0.3s ease;
}

/* Accent line at top */
.login-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--primary-hover));
}

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

.login-header img {
    margin-bottom: 1rem;
    filter: drop-shadow(0 4px 6px rgba(0, 0, 0, 0.1));
}

.login-header h3 {
    font-weight: 700;
    color: var(--text-primary);
    font-size: 1.5rem;
    letter-spacing: -0.025em;
    margin: 0;
}

[data-theme="light"] .text-white {
    color: var(--text-primary) !important;
}

[data-theme="light"] .text-white-50 {
    color: var(--text-secondary) !important;
}

.form-label {
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.form-control {
    background-color: var(--input-bg);
    border: 1px solid var(--input-border);
    color: var(--text-primary);
    padding: 0.75rem 1rem;
    border-radius: 8px;
    transition: all 0.2s ease;
}

.form-control:focus {
    background-color: var(--input-bg);
    /* Keep base color */
    border-color: var(--primary-color);
    box-shadow: 0 0 0 4px rgba(59, 130, 246, 0.15);
    color: var(--text-primary);
}

.form-check-input {
    background-color: var(--input-bg);
    border-color: var(--input-border);
    cursor: pointer;
}

.form-check-input:checked {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
}

.form-check-label {
    color: var(--text-secondary);
    font-size: 0.9rem;
    cursor: pointer;
    user-select: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-hover) 100%);
    border: none;
    padding: 0.875rem;
    font-weight: 600;
    border-radius: 8px;
    transition: all 0.2s ease;
    letter-spacing: 0.025em;
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 6px 16px rgba(59, 130, 246, 0.4);
    background: linear-gradient(135deg, var(--primary-hover) 0%, var(--primary-color) 100%);
}

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

.alert {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.2);
    color: #fca5a5;
    border-radius: 8px;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
}

[data-theme="light"] .alert {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: #b91c1c;
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.login-card {
    animation: fadeIn 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Theme Toggle Button */
.theme-toggle {
    position: absolute;
    top: 20px;
    right: 20px;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    color: var(--text-primary);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.theme-toggle:hover {
    background: var(--primary-color);
    color: white;
    transform: rotate(15deg);
}

/* Input Group Styles */
.input-group-text {
    background-color: var(--input-bg);
    border: 1px solid var(--input-border);
    border-right: none;
    color: var(--text-secondary);
}

.input-group .form-control {
    border-left: none;
}

.input-group .form-control:focus {
    z-index: 3;
}

.input-group-text+.form-control {
    border-top-left-radius: 0;
    border-bottom-left-radius: 0;
}

/* Password Toggle */
.password-toggle {
    background-color: var(--input-bg);
    border: 1px solid var(--input-border);
    border-left: none;
    color: var(--text-secondary);
    cursor: pointer;
    transition: color 0.2s ease;
}

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