body {
        background: #f6f9fa;
    }
    .auth-container {
        max-width: 900px;
        margin: 60px auto 0 auto;
        display: flex;
        flex-direction: column;
        align-items: center;
    }
    .auth-header {
        text-align: center;
        margin-bottom: 30px;
    }
    .auth-header .icon {
        background: var(--first-color, #2563eb);
        color: #fff;
        border-radius: 50%;
        width: 60px;
        height: 60px;
        display: flex;
        align-items: center;
        justify-content: center;
        margin: 0 auto 18px auto;
        font-size: 2.2rem;
        box-shadow: 0 4px 16px rgba(37,99,235,0.08);
    }
    .auth-header h1 {
        font-size: 2.5rem;
        font-weight: 700;
        margin-bottom: 8px;
        color: #22223b;
    }
    .auth-header p {
        color: #6c757d;
        font-size: 1.1rem;
    }
    .auth-cards {
        display: flex;
        gap: 32px;
        width: 100%;
        justify-content: center;
    }
    .auth-card {
        background: #fff;
        border-radius: 14px;
        box-shadow: 0 4px 20px rgba(0,0,0,0.07);
        padding: 2.2rem 2rem 1.5rem 2rem;
        flex: 1 1 340px;
        min-width: 320px;
        max-width: 400px;
        display: flex;
        flex-direction: column;
        justify-content: space-between;
        border-top: 4px solid var(--first-color, #2563eb);
    }
    .auth-card.new-user {
        border-top: 4px solid #22c55e;
    }
    .auth-card h2 {
        font-size: 1.3rem;
        font-weight: 700;
        margin-bottom: 18px;
        display: flex;
        align-items: center;
        gap: 8px;
        color: #22223b;
    }
    .auth-card .form-group {
        margin-bottom: 1.2rem;
    }
    .auth-card label {
        font-size: 1rem;
        color: #495057;
        margin-bottom: 0.4rem;
        display: block;
        font-weight: 500;
    }
    .auth-card .form-control {
        width: 100%;
        padding: 0.75rem 1rem;
        border: 2px solid #e0e0e0;
        border-radius: 12px;
        font-size: 1rem;
        background-color: #f9f9f9;
        box-sizing: border-box;
    }
    .auth-card .form-control:focus {
        border-color: var(--first-color-alt);
        background-color: #fff;
        outline: none;
    }
    .auth-card .password-input-wrapper {
        position: relative;
    }
    .auth-card .toggle-password {
        position: absolute;
        right: 10px;
        top: 50%;
        transform: translateY(-50%);
        background: none;
        border: none;
        cursor: pointer;
        padding: 0;
    }
    .auth-card .toggle-password svg {
        width: 20px;
        height: 20px;
        stroke: #666;
    }
    .auth-card .toggle-password:hover svg {
        stroke: var(--first-color-alt);
    }
    .auth-card .alert {
        background-color: #f8d7da;
        color: #721c24;
        padding: 0.75rem 1rem;
        border-radius: 10px;
        margin-bottom: 1rem;
        font-size: 0.9rem;
        border-left: 4px solid #dc3545;
    }
    .auth-card .login-btn {
        background-color: var(--first-color);
        color: white;
        padding: 0.75rem;
        border-radius: 25px;
        border: none;
        font-size: 1rem;
        cursor: pointer;
        width: 100%;
        font-weight: bold;
        margin-top: 10px;
    }
    .auth-card .login-btn:hover {
        background-color: var(--first-color-alt);
        font-weight: bold;
    }
    .auth-card .card-footer {
        text-align: center;
        padding-top: 1rem;
    }
    .auth-card .card-footer a {
        color: var(--first-color);
        text-decoration: none;
    }
    .auth-card .card-footer a:hover {
        color: var(--first-color-alt);
    }
    @media (max-width: 900px) {
        .auth-cards {
            flex-direction: column;
            gap: 24px;
        }
    }
    @media (max-width: 1200px) {
        .auth-container {
            max-width: 98vw;
            margin: 40px auto 0 auto;
        }
        .auth-cards {
            gap: 18px;
        }
        .auth-card {
            min-width: 260px;
            max-width: 360px;
            padding: 1.5rem 1rem 1rem 1rem;
        }
    }
    @media (max-width: 900px) {
        .auth-cards {
            flex-direction: column;
            gap: 18px;
            align-items: center;
        }
        .auth-card {
            width: 90vw;
            min-width: unset;
            max-width: 420px;
        }
    }
    @media (max-width: 600px) {
        .auth-container {
            margin: 20px auto 0 auto;
            padding: 0 4px;
        }
        .auth-header h1 {
            font-size: 1.5rem;
        }
        .auth-header p {
            font-size: 1rem;
        }
        .auth-card {
            padding: 1rem 0.5rem 0.7rem 0.5rem;
            font-size: 0.97rem;
            max-width: 98vw;
        }
        .auth-card h2 {
            font-size: 1.05rem;
        }
        .auth-card .login-btn, .auth-card .form-control {
            font-size: 0.97rem;
        }
    }